A.D. Scout, the Sparrow

  THE A.D. Scout, or Sparrow, was designed in 1915 by Harris Booth and was intended to be an anti-Zeppelin fighter. The armament was to have been a Davis recoilless quick-firing gun, a weapon in which the Admiralty were then interested.
  The Sparrow was a single-engined pusher biplane of unusual appearance. Sketches of a wind-tunnel model depict a two-bay biplane of fairly large gap, with the nacelle attached to the upper wing: it appeared that the spars of the wing were attached to the underside of the upper longerons of the nacelle. An enormously tall undercarriage was necessary, but the track of the wheels was absurdly narrow. Presumably it was hoped that the widely separated twin tail-skids would provide sufficient ground stability.
  The tail-booms were parallel in plan and elevation, and supported a single tailplane of great span. There were two fins and rudders.
  The nacelle was an ugly, angular affair which had obviously been designed round the gun: the weapon was mounted on the floor of the nacelle, and the barrel protruded two feet in front. The engine was an 80 h.p. Gnome rotary mounted at the rear of the nacelle. The pilot sat well forward of the wings and must have had an excellent all-round view from his cockpit.
  Four A.D. Scouts were ordered - two from the Blackburn company and two from Hewlett & Blondeau. It is uncertain whether all were built, but at least one was completed and was flown at Chingford. The Sparrow turned out to be considerably overweight, and on test it proved to be unsatisfactory and tricky to fly. It was quickly abandoned.


SPECIFICATION
  Manufacturing Contractors: The Blackburn Aeroplane and Motor Co., Olympia, Leeds, Yorkshire. Hewlett & Blondeau, Ltd., Leagrave, Bedfordshire.
  Power: 80 h.p. Gnome.
  Approximate Dimensions: (Derived from drawings of a wind-tunnel model.) Span: upper 32 ft 4 in., lower 33 ft 5 in. Length: 22 ft 9 in., 24 ft 9 in. over gun. Height: 10 ft 3 in. Chord: 4 ft 6 in. Gap: 5 ft 9 1/2 in. Stagger: 1 ft 7 in. Dihedral: 3 30'. Span of tail: 21 ft. Wheel track: 2 ft 7 in. Track of tail-skids: 11 ft 2 in. Airscrew diameter: 9 ft.
  Serial Numbers: 1452-1453: ordered from Hewlett & Blondeau under Contract No. 38552/15. 1536-1537: ordered from Blackburn.

A.D. Seaplane Type 1000

  BRITISH experiments in dropping torpedoes from aircraft began in 1913, and had from their inception the blessing of Captain Murray F. Sueter (later Rear-Admiral Sir Murray Sueter, C.B.), the Director of the Air Department of the Admiralty.
  In 1914, Harris Booth of the Air Department designed an enormous twin-float seaplane which was intended to be used as a bomber or torpedo-carrier. When it appeared it was the largest aeroplane of any type which had been built in Britain. It was powered by three 310 h.p. Sunbeam engines, two of which were installed as tractor units at the forward ends of the twin fuselages. The third engine was mounted at the rear of the central control cabin (which was much too imposing a structure to be called a mere nacelle) and drove a pusher airscrew. All three engines had cowlings which were remarkably ugly and cumbersome. The control cabin looked uncommonly like a domestic greenhouse, and was little better streamlined. The machine was to have had a crew of five.
  The serial number 1000 was provisionally allotted for the type which, in accordance with the Admiralty practice of the time, thereupon became known as the Type 1000.
  It is believed that seven examples were ordered, but only one, No. 1358, was completed. Construction was undertaken by J. Samuel White & Co., Ltd., of Cowes, the makers of the Wight seaplanes; and consequently the A.D. 1000 has been wrongly described as a Wight type.
  It was not a success. Its clumsy appearance rightly betokened excessive structural weight, and its floats were too flimsy: they were unable to withstand even a slight sea.
  The A.D. Type 1000 was abandoned, and probably ended its days at Felixstowe. It was there in the summer of 1916. In his book From Sea to Sky, Air Chief Marshal Sir Arthur Longmore wrote of it:
  “Another boat of weird design had been delivered some time before; it looked like a floating conservatory with two floats and a double fuselage and three engines; but it was evidently not very popular for it had stayed in its shed ever since.”


SPECIFICATION
  Manufacturers: J. Samuel White & Co., Ltd., Cowes, Isle of Wight.
  Power: Three 310 h.p. Sunbeam.
  Dimensions: Span: 115 ft.
  Serial Numbers: 1000: ordered under Contract No. C.P.01516/14. 1355-1360. No. 1000, Nos. 1355-1357 and Nos. 1359-1360 were not delivered.

A.D. Navyplane

  THE Navyplane was a two-seat pusher biplane floatplane sponsored by the Air Department of the Admiralty in 1916, and intended for reconnaissance and bombing duties. It was designed by Harold Bolas of the Air Department in collaboration with Messrs R. J. Mitchell and Richardson of the Supermarine Aviation Works, Ltd., to which company the construction of the machine was entrusted.
  Eight weeks after the drawings were received by the Supermarine company the Navyplane was completed, an achievement which brought the manufacturers a letter of appreciation from Commodore Murray F. Sueter. Serial numbers were allotted for seven machines but only one was built. The Navyplane’s test flights were carried out in August, 1916, by Lieutenant-Commander John Seddon.
  Structurally the Navyplane was a two-bay biplane with the tail unit supported on four tail-booms, and its most remarkable feature was its monocoque nacelle which, complete with seats and floor-bearers, weighed no more than 80 lb. The nacelle had a sectional glass screen which was led round the nose from the forward windscreen to a point under the pilot’s seat; this gave the crew a good forward and downward view. The Navyplane carried wireless, and the observer had a Lewis gun on a special flexible mounting. The nacelle was mounted mid-way between the wings. The wings themselves were made in three parts and only the outer portions were rigged with dihedral. The tailplane was attached to the upper tail-booms and was of the inverted camber type.
  The main floats were pontoon structures and were connected horizontally by only one cross-bar. Each of the twin tail-floats had a water-rudder.
  The Navyplane’s original power-plant was a new type of radial engine, the 150 h.p. Smith Static. The design of this engine was brought to England in January, 1915, by an American, John W. Smith, who succeeded in interesting the Admiralty in it almost immediately. The Smith Static was a ten-cylinder single-row radial engine which had offset connecting rods bearing alternately on the cranks of a two-throw crankshaft. The engine must have been reasonably successful. It was tested on the bench and in the air to the satisfaction of the Admiralty. A contract for its production was given to Messrs Heenan & Froude, but only a few were delivered before the Armistice.
  The Smith engine was installed quite neatly in the A.D. Navyplane but was later replaced by a 150 h.p. A.R.I. rotary engine. The reason for the change is uncertain, but difficulty may have been experienced with the cooling of the radial. With the A.R.I engine the Navyplane was tested in May, 1917, but with no military load and no observer the performance was very poor.


SPECIFICATION

  Manufacturers: The Supermarine Aviation Works Ltd., Woolston, Southampton.
  Power: 150 h.p. Smith Static radial engine; later, 150 h.p. A.R.I rotary engine.
  Dimensions: Span: 36 ft. Length: 27 ft 9 in. Height: 12 ft 9 in. Chord: 5 ft. Gap: 6 ft 6 in. Stagger: nil. Span of tail: 15 ft 6 in. Airscrew diameter: 8 ft 10 in.
  Areas: Wings: 364 sq ft.
Weights (lb) and Performance:
Engine Smith Static A.R.I
Date of Trial Report - 15 May, ’9'7
Weight empty 2,100 2,042
Military load - nil
Crew - 180
Fuel and oil - 328
Weight loaded 3,102 2,550
Maximum speed (m.p.h.) at 2,000 ft 75 64-5
Climb to 2,000 ft - 30 min
Service ceiling (feet) - 1,300
Endurance (hours) 6 6

  Armament: One Lewis machine-gun on a movable mounting for the observer.
  Serial Numbers: 9095-9096. (9096 was not built.) N.1070-N.1074: cancelled.

A.D. Flying Boat

  THIS two-seat patrol flying boat was designed by the Air Department of the Admiralty. The design work was carried out in the autumn of 1915 under Harris Booth, and the hull was one of the first to be designed by Lieutenant Linton Hope.
  Construction of the first hull was undertaken by May, Harden & May, and the completion of the aircraft was entrusted to Pemberton-Billing, Ltd. The detail design was carried out by Harold Bolas, Harold Yendall and Clifford W. Tinson of the Air Department, who went to the Pemberton-Billing works specially for the purpose.
  Two prototypes, numbered 1412 and 1413, were flying in 1916. These machines differed slightly in detail: the first had a semi-enclosed bow cockpit, whilst the second had an open bow cockpit and a slightly deeper radiator.
  At first, considerable trouble was experienced, for the machine porpoised badly on the water. The Admiralty sought the advice of the scientists who were associated with the experimental work carried out at the Froude National Tank of the National Physical Laboratory. Tests were carried out in August, 1916, at Southampton but were discontinued before the trouble was eradicated. At one time the step was moved two feet farther aft at the suggestion of Squadron Commander J. L. Travers, but that did not cure the machine of porpoising.
  A solution must have been found at a later stage, for production was undertaken on a small scale; the production machines were generally similar to No. 1413. The engine for which the original installation was designed was the 150 h.p. Sunbeam Nubian, but both prototypes and production A.D. Flying Boats were built with Hispano-Suiza engines. The standard power-plant was the 200 h.p. geared Hispano-Suiza, but N.1525 at least had the 150 h.p. direct-drive engine of the same make.
  The A.D. Flying Boat was flown in February, 1917, by Squadron Commander Travers, Flight-Lieutenant Goodwin and Flight-Lieutenant Barlow, when some excellent performances were recorded. One A.D. Boat rode out a 38 m.p.h. gale for seven hours in an open harbour without damage and shipped only 120 lb of water.
  The hull was a wooden monocoque of good form and sturdy construction; it was claimed that the A.D. Flying Boats were stronger, weight for weight, than the larger F boats. One was subjected to rather drastic tests to prove the strength of the hull: it successfully withstood thirty-six successive heavy landings in which it was deliberately stalled at some 10-12 feet above the water. An unusual feature of the design was the provision for the fitting of wheels to enable the machine to be flown from the deck of a carrier vessel; after take-off the wheels were jettisoned.
  The upper tailplane was of inverted aerofoil section and was mounted at a slightly negative angle of incidence, for it was thought that in the event of engine failure the reversed camber would prevent the tail from dropping. The lower tailplane, which was awash when the flying boat was taxying in heavy seas, was covered with plywood and was a watertight structure. The wings could be folded, presumably to conserve space when carried on board ship, but contrary to contemporary practice they folded forwards.
  One of the later production A.D. Flying Boats, N.1719, was used in experiments with hydrovanes. Two were fitted: one was just aft of the pilot’s cockpit, the other about six feet aft of the trailing edge of the wing. Each hydrovane was some 18 inches below the keel of the hull.
  In September, 1918, an A.D. Flying Boat was tested with the 200 h.p. Wolseley Python engine. The installation was experimental, and performance was not good.
  The A.D. Flying Boats did not distinguish themselves in any operational way during the war, but with the coming of peace they provided the basis for the successful Supermarine Channel type, which, powered by the 160 h.p. Beardmore or 230 h.p. Siddeley Puma, was one of the earliest commercial flying boats to go into service and was used in many parts of the world.

SPECIFICATION
  Manufacturers: Pemberton-Billing, Ltd. (later the Supermarine Aviation Works, Ltd.), Woolston, Southampton.
  Power: 150 h.p. Hispano-Suiza; 200 h.p. Hispano-Suiza; 200 h.p. Wolseley Python.
  Dimensions: Span: upper 50 ft 3 15/16 in., lower 39 ft 7 1/4 in. Length: 30 ft 7 in. Height: 13 ft 1 in. Chord: 5 ft 6 in. Gap: 7 ft. Stagger: nil. Dihedral: mainplanes 4°, lower tailplane 2° 30'. Incidence: mainplanes 30, upper tailplane -0° 30', lower tailplane + 5°. Span of tail: upper 9 ft 10 in., lower 8 ft 4 in.
  Areas: Wings: 479 sq ft. Tailplanes: total 60 sq ft. Fins and rudders: total 40 sq ft.
  Weights (lb) and Performance:
Engine 150 h.p.
Hispano-Suiza 200 h.p. Hispano-Suiza 200 h.p. Wolseley Python
No. of Trial Report 8A - N.M.214
Date of Trial Report July 3, 1917 July 12, 1917 September 21, 1918
Type of airscrew used on trial A.D.645 A.B.6622
Weight empty 2,400 2,508 2,360
Military load 216 206 176
Crew 360 360 360
Fuel and oil 351 493 492
Weight loaded 3.327 3,567 3,388
Maximum speed (m.p.h.) at
   2,000 ft 91 100 87-5
   6,500 ft 83 99 87
   10,000 ft - 90 -
m. s. m. s. m. s.
Climb to
   2,000 ft 6 00 3 00 5 35
   6,500 ft 26 00 14 00 23 50
   10,000 ft - - 30 00 55 00
Service ceiling (feet) 7.500 11,000 8,800
Endurance (hours) 5 4 1/2 3 1/2| at 3,000 ft

  Armament: One Lewis machine-gun on movable mounting in bow cockpit. A small bomb load could be carried.
  Production: Serial numbers indicate that two prototypes and at least twenty-seven production machines were built. On April ist, 1918, when the Air Department handed over to the newly-formed Royal Air Force, eighteen A.D. Flying Boats were in service, nine were under construction or on order, and one had been written off.
  Serial Numbers: 1412-1413: ordered under Contract No. C.P. 109611/15. N. 1290-N.1299: ordered under Contract No. A.S.1449. N.1291-N.1299 were not built. N.1520-N.1529: ordered under Contract No. A.S.5388/17. N.1710-N.1719: ordered under Contract No. A.S.20798. N.2450-N.2455: ordered under Contract No. A.S. 18936.
  Notes on Individual Machines: N. 1525 had the 150 h.p. Hispano-Suiza engine. N.1719 was experimentally fitted with hydrovanes below the hull.
  Costs:
   Airframe, including hull but without engine, instruments and gun £2,853 8s.
   Airframe without hull £1,925 0s.
   200 h.p. Hispano-Suiza engine £1,004 0s.

Alcock Scout

  IN 1917, Flight-Lieutenant J. W. Alcock, who was later to achieve fame for his trans-Atlantic flight with Arthur Whitten Brown in 1919, was serving with No. 2 Wing, R.N.A.S., at Mudros, in the Aegean Sea. While there he made a single-seat fighter biplane, which he called the “Sopwith Mouse”, and which was also known as the Alcock A.1.
  This aircraft consisted almost wholly of Sopwith Triplane and Pup components. The fuselage, undercarriage, and most of the lower wing belonged to a Sopwith Triplane, whilst much of the upper wing had originally belonged to a Pup. It appears that a new centre-section was made for the upper wing, and that a centre-section was also fitted to the lower wing. The fuselage appeared to rest on top of the lower main-plane. Two-bay interplane bracing was used, and the interplane struts converged downwards to meet the more closely-spaced spars of the lower wing. The gap was such that the upper wing was brought low above the fuselage, and interfered very little with the pilot’s view.
  It is hard to determine how much of the tail unit came from other aircraft, but the rudder might have belonged to a Sopwith type. Triangular fins were fitted, one above and one below the fuselage; and the tail-skid was apparently attached to the rudder-post. The tailplane was mounted centrally on the fuselage.
  The Alcock machine was at first fitted with a 100 h.p. Gnome Monosoupape rotary engine, but a 110 h.p. Clerget was later fitted. It is believed that some of the components were taken from the Sopwith Triplane which crashed at Mudros on September 3rd, 1917. Much of the mathematical work involved in the building of the aircraft was done by Commander Constantine of the Greek Navy, who was then in command of the Greek Air Force at Mudros.
  Contrary to the official history, Alcock never flew his “Sopwith Mouse”, for it had not been completed when he was taken prisoner by the Turks on the night of September 30th, 1917: he and his crew (Lieutenant S. J. Wise and Lieutenant H. Aird) were captured when No. 2 Wing’s solitary Handley Page O/100 was forced down in the Gulf of Xeros.
  But the Alcock Scout was completed and flown. While Alcock was in the civil jail at Seraskerat, Constantinople, he received this message from Wing-Captain F. R. Scarlett, C.B., D.S.O., on October 18th, 1917: “Your baby was taken for an airing, but is still having trouble with teeth. She has now been fitted with new clothing. Now a great improvement in health.” It is believed that the Alcock A.I was first flown on October 15th, 1917.
  Early in 1918 the machine was flown over to Stavros by Flight-Lieutenant Starbuck, and it is believed that it was crashed there by that officer.
  The foregoing history is based on notes provided by former members of No. 2 Wing, R.N.A.S., who were at Mudros when the Alcock A.I was built; it is very different from the account which appears in Volume V of The War in the Air, the official history. The latter account tells of an aircraft of Alcock’s design fitted with a Benz engine which had been taken from a Friedrichshafen bomber shot down in April, 1917, and goes on to relate how Alcock flew it to attack three enemy seaplanes on September 30th, 1917.
  That story is inaccurate, however, for the Alcock A.1 could not have been fitted with a Benz engine, and Alcock was flying a Camel on the occasion in question. It may indicate that he designed an aeroplane round the Benz engine, for it was stated that drawings were sent home from Mudros.


SPECIFICATION
  Power: 100 h.p. Gnome Monosoupape; 110 h.p. Clerget.
  Armament: Two fixed, forward-firing Vickers machine-guns, synchronised to fire through the airscrew. Service Use: No. 2 Wing, R.N.A.S., Mudros; also flown at Stavros.

Armstrong Whitworth F.K. 1

  THE original aircraft manufacturing firm which bore the name of Armstrong Whitworth came into existence in 1914 as the Aeroplane Department of the large engineering firm of Sir W. G. Armstrong, Whitworth & Co., Ltd. The first works manager was that great Dutchman, Frederick Koolhoven.
  The little single-seat scout which was designated Armstrong Whitworth F.K.1 was not Koolhoven’s first essay in aeroplane design, for he had earlier done much work on several of the Deperdussin monoplanes, but it was his first design for the Armstrong Whitworth company.
  The Armstrong Whitworth F.K.1 was a rather frail-looking little biplane which appeared in September, 1914. Even at that early date it showed evidence of having been designed with an eye to production, for its layout was essentially simple. The fuselage was reminiscent of the pre-war Morane-Saulnier monoplanes; so also was the plan-form of the wing-tips. The tail unit betrayed further Morane influence, for there was at first no tailplane but only a balanced elevator. The aircraft had been meant to have the to 80 h.p. Gnome rotary engine, but only a 50 h.p. Gnome could be obtained. There was no alternative but to install the lower-powered engine.
  The first flight of the F.K.1 was made by Koolhoven himself. The tail unit was subsequently modified, and a fixed tailplane and plain elevator were fitted. A further modification was the fitting of new, enlarged ailerons which had a pronounced inverse taper.
  The F.K.1 was underpowered with only the very nominal 50 h.p. of its Gnome engine, and its performance was no improvement on that of the more powerful contemporary Sopwith, Bristol and Martinsyde Scouts. No development was undertaken.


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Power: 50 h.p. Gnome.
  Performance: Maximum speed: 75 m.p.h. Stalling speed: 30 m.p.h.

Armstrong Whitworth F.K.3

  IN the summer of 1914 it was officially decided to adopt the B.E.2C as a standard type for both the R.F.C. and the R.N.A.S., and among the first manufacturers to be awarded contracts for its production were Sir W. G. Armstrong, Whitworth & Co., Ltd.
  When the necessary drawings were received from the Royal Aircraft Factory, study of them led the firm to declare the B.E.ac to be complicated and difficult to construct. Armstrong Whitworths offered to design and produce an aeroplane which would be structurally simpler than the B.E.2c but equally efficient. The firm were granted permission to do so, and Frederick Koolhoven produced the design of the F.K.3. Work began in August, 1915, and, after the successful completion of official trials, large orders for F.K.3S were placed with Armstrong Whitworth and Messrs Hewlett & Blondeau.
  In general appearance the F.K.3 bore a certain resemblance to the B.E.2c, particularly in its original form, when it carried its crew in two separate cockpits similar in shape to those of the B.E., and the pilot occupied the rear seat.
  An interesting experimental modification was made to an early F.K.3 in 1915. Koolhoven added a third mainplane above the normal biplane wings in order to measure the increased lift and drag produced by the arrangement. This machine flew well and had a remarkably flat glide. It seems probable that it may have provided some data for the design of the Armstrong Whitworth F.K.12 triplane.
  Production F.K.3s showed several major differences from the prototype, chief of which was the interchange of the pilot’s and observer’s seats. The crew occupied one large communal cockpit, somewhat similar to that of the D.H.6. With the pilot in the front seat, the observer could use a gun much more effectively. Dual controls were provided. The shape of the fin and rudder was modified to be neater in appearance but greater in area than that of the prototype; the rudder was still a horn-balanced surface. The undercarriage was an interesting structure which included a central skid and yet had oleo shock absorbers attached to the fuselage, at a time when rubber cord was the almost universal shock absorbing medium. The design of the oleo components was influenced by the recoil mechanism of the famous French 75 mm gun.
  The operational service of the F.K.3 was given in the Middle East theatre of war. In Macedonia the type was used by No. 47 Squadron, which arrived at Salonika on September 19th, 1916, and remained in service with that unit until 1918.
  Proof of the F.K.3’s sturdiness was provided by an incident which occurred in the course of a combat over Hudova on December 22nd, 1916. The F.K.3 flown by Second Lieutenant W. H. Farrow (observer: Second Lieutenant F. C. Brooks) collided with an enemy machine. The Armstrong Whitworth’s starboard wheel struck the German biplane’s upper wing, and the enemy machine disappeared into the clouds below. Despite a troublesome engine, Farrow landed his F.K.3 safely at Snevce.
  The F.K.3 was called upon to perform a variety of duties by No. 47 Squadron. Bombing attacks, such as that made on Hudova on February 1 ith, 1917, when four F.K.3s and a B.E.12 reached the target, were not uncommon. Hudova was bombed frequently, and on such raids the machine was usually flown without an observer, for it was unable to lift both bombs and a second crew-member.
  Artillery cooperation and contact patrols were also performed by the hard-working F.K.3s, not without losses, for the enemy did not make the mistake of using only second-class or outmoded machines on the lesser fronts.
  At home the F.K.3’s normal use was as a trainer, a duty for which its viceless flying characteristics made it admirably suitable. It was almost as foolproof as the D.H.6, but was much lighter on the controls than either “The Clutching Hand” or the B.E.2C. The F.K.3 was capable of performing all the aerobatics which were in practice at the time of its existence. The type was also used for training observers, when a camera gun was carried. To the R.F.C. it was familiarly known as the “Little Ack”, to distinguish it from the later F.K.8 or “Big Ack”.
  After the adoption of the Avro 504 as the standard training aeroplane, the F.K.3 was almost completely supplanted, but a fair number survived until the Armistice. Some, indeed, were sufficiently long-lived to go on the British Civil Register as G-EABY, G-EABZ, G-EAEU and G-EALK. Of these, G-EABY at least was fitted with a plain vee undercarriage.

SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Other Contractors: Hewlett & Blondeau, Ltd., Oak Road, Leagrave, Luton.
  Power: 90 h.p. R.A.F. Ia; 105 h.p. R.A.F. Ib.
  Dimensions: Span: 40 ft 0 5/8 in. Length: 29ft. Height: 11 ft 10 3/4 in. Chord: 5 ft 8 1/4 in. Gap: 5 ft 11 in. Stagger: 1 ft 11 5/8 in. at centre section, 1 ft 11 9/16 in. at outer struts. Dihedral: upper 3° 30', lower 2° 30'. Incidence: 1° 40'. Span of tail: 14 ft 3 in. Airscrew diameter: 9 ft.
  Areas: Wings: upper 229 sq ft, lower 213 sq ft, total 442 sq ft. Ailerons: each 16 sq ft, total 64 sq ft. Tailplane: 27 sq ft. Elevators: 22 sq ft. Fin: 5-8 sq ft. Rudder: 9-5 sq ft.

  Weights (lb) and Performance:
Engine R.A.F. 1a R.A.F. 1b
No. of Trial Report M.40 M.47
Date of Trial Report May, 1916 June, 1916
Type of airscrew used on trial T.7448 T.7448
Weight empty 1,386 I>375
Military load 80 80
Crew 360 320
Fuel and oil 230 235
Loaded 2,056 2,010
Maximum speed (m.p.h.) at ground level 87 -
1,000 ft 85 -
6,500 ft - 88
8,000 ft 81 -
10,000 ft - 80
m. s. m. s.
Climb to 1,000 ft 3 00 - -
2,000 ft 7 00 - -
3,000 ft 10 30 - -
4,000 ft 14 00 - -
5,000 ft 19 00 - -
6,000 ft 24 00 - -
6,500 ft 26 30 12 00
7,000 ft 29 00 - -
8,000 ft 36 00 - -
9,000 ft 41 00 - -
10,000 ft 48 56 - -
11,000 ft 66 00 - -
12,000 ft 74 00 - -
12,300 ft 78 00 - -
Service ceiling (feet) 12,000 13,000
Endurance at 8,000 (hours) 3 2 1/2

  Tankage: Petrol: 28 gallons. Oil: 2-6 gallons.
  Armament: One Lewis machine-gun on pillar mounting at the rear of the cockpit. The bomb load, carried in external racks, could include bombs of 16 lb, 100 lb, or 112 lb.
  Service Use: Macedonia: No. 47 Squadron, R.F.C. Training: Used at various aerodromes, including No. 31 Training Squadron, Wyton; No. 35 Reserve Squadron, Northolt; Schools of Aerial Gunnery at Hythe and Turnberry; and at Stirling, Dymchurch and Marske. Also used in Egypt.
  Production and Allocation: No precise figures for production and original allocations can be given, because the Armstrong Whitworth F.K.3 and F.K.8 were grouped together in the official statistics. Serial numbers indicate that at least 500 F.K.3S were ordered; and it seems obvious that the four Armstrong Whitworths delivered to Training Units in 1915 must have been F.K.3s, as also would be most of the eighty delivered in 1916. On October 31st, 1918, the Royal Air Force had sixty-two F.K.3s on charge: fifty-one were at schools and home aerodromes, six were in Egypt, three in Palestine, one was at an Aeroplane Repair Depot and one at an experimental unit.
  Serial Numbers: 5328-5334, 5614 and 6186-6227 were ordered from Armstrong Whitworth under Contract No. 94/A/103. 5504-5553. A.1461-A.1510, A.8091-A.8140 and B.9501-B.9800 were ordered from Hewlett & Blondeau.
  Notes on Individual Machines: A.1484: used by No. 35 Reserve Squadron. B.9518: became G-EABZ. B.9594: used at Marske. B.9603: became G-EALK. B.9612: became G-EAEU. B.9629: became G-EABY.
  Costs:
   Airframe without engine, instruments and gun £1,127 10s.
   R.A.F. 1a engine £522 10s.

Armstrong Whitworth F.K. 10

  IT has been said, not without some truth, that almost every variation of the aeroplane form of aircraft was tried out during the 1914-18 war by one or other of the combatants. Monoplanes, biplanes and triplanes appeared in astonishing variety and profusion, and the quadruplane form was built and flown in Britain and Germany.
  In Britain, at least four quadruplane types were built. The Supermarine concern built two large twin-engined quadruplanes, the P.B.29 of 1915 and the Night Hawk of 1916; the little Wight quadruplane single-seat fighter appeared in three slightly different forms; and the two-seat fighter-reconnaissance type was represented by the Armstrong Whitworth F.K.10. On the German side, at least two single-seat fighter quadruplanes were built; namely the Naglo with the 160 h.p. Benz, and the Euler with an Oberursel rotary engine.
  The Armstrong Whitworth F.K.10 provided an excellent example of the striking originality of thought possessed by Frederick Koolhoven. The prototype had a slender fuselage, a fixed tailplane, and an ugly horn-balanced rudder; the engine was the 110 h.p. Clerget. It is doubtful whether any military equipment was fitted to this machine, and it seems probable that it may have been built solely to test the quadruplane wing arrangement.
  The later prototypes had the same wing arrangement as the first, but the fuselage was more portly and the tail unit had been re-designed. There was now no fixed tailplane but only a balanced elevator reminiscent of the Morane-Saulnier monoplanes, and the vertical tail surfaces were of more pleasing form with approximately equal areas of fin above and below the fuselage. The 130 h.p. Clerget replaced the 110 h.p. engine of the first machine, but at least one F.K.10 had a 110 h.p. Le Rhone.
  The pilot, from his cockpit ahead of the wings, had a remarkably good view in almost all forward and upward directions. This was one of the principal reasons for the adoption of the quadruplane layout, and good manoeuvrability was probably hoped for as a result of the use of four ailerons on each side and the compression of the wing area into a short span.
  Armament was fitted to these F.K.10s, and consisted of a fixed synchronised Vickers gun for the pilot and a stripped Lewis on a rocking-post mounting for the observer.
  A small batch of F.K.10s were ordered for the R.F.C. from Angus Sanderson & Co., presumably owing to Armstrong Whitworth’s pre-occupation with production of the F.K.8.
  The R.N.A.S. were also interested in the type and ordered a few from other contractors. Two machines, N.511 and N.512, were built by the Phoenix Dynamo Manufacturing Co., Ltd., in 1917. The first was intended to be a two-seat fighter, for which purpose a Scarff ring-mounting was provided for the observer’s Lewis gun; the second machine, N.512, was built as a bomber. N.511 underwent its trials at Boroughbridge on April 26th, 1917.
  The Phoenix-built F.K.10s differed in detail from the machines built by Armstrong Whitworth. They had horse-shoe cowlings instead of full circular; the coaming in front of the pilot’s cockpit was fuller and no windscreen was fitted; and small end-plates were fitted at the inboard ends of the bottom mainplanes.
  All the F.K.10s were characterised by the heavily staggered wings connected by a single “plank” interplane strut and similar centre section struts, and by the peculiar single-strut undercarriage braced in three planes by cross-wires. The resulting structure did not look particularly strong, but presumably it worked well enough.
  The R.F.C. flew an F.K.10 at Gosport, and the R.N.A.S. quadruplanes were flown at Manston; but the F.K.10 was not a good aeroplane, and production was not undertaken. The machine must have been sensitive on the elevators in the same way as the Moranes were, and it suffered from a form of wing flutter. The type was ultimately abandoned and four F.K.10s were scrapped at Manston in 1917.
  A remarkable development was projected as the F.K.11. It was to consist of the fuselage of an F.K.10 fitted with fifteen narrow-chord mainplanes, heavily staggered and mounted close together.


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Other Contractors: The Phoenix Dynamo Manufacturing Co., Ltd., Bradford; Angus Sanderson & Co., Newcastle-on-Tyne.
  Power: 110 h.p. Clerget; 130 h.p. Clerget; 110 h.p. Le Rhone.
  Dimensions: Span: 27 ft 10 in. Length: 22 ft 3 in. Height: 11 ft 6 in. Chord: 3 ft 7 in. Gap: 2 ft 8 in. Stagger: 1 ft 5 in. Dihedral: 1° 30'. Incidence: 3°.
  Areas: Wings: top 102-6 sq ft, second 92-6 sq ft, third 92-6 sq ft, bottom 102-6 sq ft; total 390-4 sq ft. Ailerons: each 8-4 sq ft, total 67-2 sq ft. Elevators: 16 sq ft. Fin: 1-9 sq ft. Rudder: 8 sq ft.

Weights (lb) and Performance:
Engine 110 h.p. Clerget 130 h.p. Clerget Manufacturer’s figures for 130 h.p.
No. of Trial Report M.77 M.82 -
Date of Trial Report Dec. 1916 Mar., 1917 -
Type of airscrew used on trial L.P.710C L.P.710C -
Weight empty 1,226 1,236 1,143
Military load 160 160 -
Crew 360 360 -
Fuel and oil 292 263 -
Weight loaded 2,038 2,019 1,804
Maximum speed (m.p.h.)
   at ground level - - 105
   6,500 ft 94 84 -
   10,000 ft 87-5 74 99

m. s. m. s. m. s.
Climb to
   6,500 ft 14 20 15 50 - -
   10,000 ft 23 35 37 10 17 00
Service ceiling (feet) 13,000 10,000 -
Endurance (hours) 3 2 1/2 -

  Armament: One fixed forward-firing Vickers machine-gun mounted centrally above the engine cowling and synchronised to fire through the airscrew; one Lewis machine-gun on rocking-post mounting or Scarff ring-mounting in rear cockpit.
  Service Use: Flown by the R.F.C. at Gosport and by the R.N.A.S. at Manston.
  Production and Allocation: Serial numbers were allotted for at least eleven Armstrong Whitworth F.K.10s, but all may not have been completed. One was delivered to the R.F.C. Training Unit at Gosport in 1916.
  Serial Numbers: A.5212-A.5214: built by Armstrong Whitworth under Contract No. 87/A/1254. B.3996-B.4000: built by Angus Sanderson. N.511-N.512: built by Phoenix Dynamo Mfg. Co. under Contract No. C.P.135178/16. N.514: built under Contract No. C.P.100565/16.

Armstrong Whitworth F.K.12

  THAT excellent aero-engine, the 250 h.p. Rolls-Royce which was later named Eagle, was originally designed and developed as a power unit for seaplanes. About the end of January, 1916, the Admiralty transferred a few of these engines to the War Office for experimental purposes; and the aircraft manufacturers of the day were invited to submit designs for multi-seat escort fighters embodying the Rolls-Royce engine. No doubt it was hoped to produce an aeroplane capable of defeating the Fokker monoplane, which was then coming into menacing prominence.
  Several firms submitted designs to meet the specification, which demanded a maximum endurance of seven hours to enable the machine to be used for anti-Zeppelin work if need be; but only Armstrong Whitworth, Sopwith and Vickers were awarded contracts for the construction of prototypes. All three designs were highly unorthodox, and all provided accommodation for their gunners in unusual positions.
  The Armstrong Whitworth design was the F.K.12, a big triplane which appeared in two different forms. The version which apparently came first was probably the most remarkable British aeroplane of the 1914-18 war. Its central mainplane was of much greater span than the top and bottom wings, and on it the fuselage was mounted almost symmetrically. There was virtually no forward-reaching nose on the fuselage; the airscrew revolved just in front of the leading edge of the central wing.
  The undercarriage consisted of a central unit carrying two main wheels on a sprung leg, and a small sprung wheel under each wing tip. A long pylon just behind the trailing edge of the bottom wing was fitted with a skid which kept the tail of the fuselage clear of the ground.
  The central mainplane carried two nacelles for gunners, each of whom apparently was to have had a Lewis gun on a rocking-post mounting. The gunners were in front of the tractor airscrew and had a fine field of fire in all forward directions.
  The second F.K.12 had a similar wing configuration, but was a much more cumbersome machine. The wing span and area were increased, and the wings had two bays of interplane bracing. The fuselage was more conventional in appearance, but was deeper and filled the gap between middle and bottom mainplanes. The long nose must have interfered with the gunners’ view. The wing-mounted nacelles were retained, but were of different form and were underslung from the centre wing. The undercarriage consisted of two twin-wheel units under the fuselage. Serial numbers were allotted for four prototypes, but it is doubtful whether all were built.
  The Armstrong Whitworth F.K.12 was tested by Peter Legh, but its performance fell short of expectations. Furthermore, in common with the Sopwith and Vickers types, it appeared at about the same time as an effective British interrupter gear for machine-guns. Development was abandoned in favour of more conventional designs which could be effectively armed.


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Power: 250 h.p. Rolls-Royce.
  Armament: Two Lewis machine-guns, one on a rocking-post mounting in each outboard nacelle.
  Serial Numbers: 7838-7841.

Armstrong Whitworth F.K.8

  TWO of the nineteen V.C.s awarded to members of the British flying services during the 1914-18 war were won on Armstrong Whitworth F.K.8s, yet the type is one of the less well-known aircraft of its period. Why this should be so is something of a mystery, for the F.K.8 gave excellent service on several fronts and proved itself a redoubtable opponent to the German single-seat fighters on more than one occasion. A possible reason for its obscurity might be that it did a good job of work, unobtrusively and without attracting undue praise or blame. It was popular with its pilots, to whom it was familiarly known as the “Big Ack”.
  The F.K.8 was, of course, designed by Frederick Koolhoven, and bore a family resemblance to the earlier F.K.3. Like the F.K.3, it had staggered wings with two-bay bracing and greater dihedral on the upper wings than on the lower, and the vertical tail assembly was of typical Koolhoven design.
  The prototype F.K.8 flew in May, 1916, and the first R.F.C. squadron to have the type was No. 35, which went to France fully equipped with F.K.8s on January 24th, 1917. No. 2 Squadron began to reequip with Big Acks in April, 1917; No. 10 received the type in July, 1917, No. 8 in August, 1917, and No. 82 went to France on November 20th, 1917, with the F.K.8 as its equipment. With these units in France, with Squadrons Nos. 17 and 47 in Macedonia, and with No. 142 in Palestine, the Big Ack gave sterling service as a reconnaissance and bombing machine until the Armistice.
  The standard production F.K.8s had at first the 120 h.p. Beardmore engine, but later the 160 h.p. Beardmore was fitted. The engine cowling was at first a decidedly angular affair in which straight lines predominated, but later machines had a redesigned nose which was rounded in side elevation. There were long upright radiator blocks on either side of the fuselage, their upper halves forming an inverted V immediately in front of the centre line of the upper mainplane. The original distinctive undercarriage was a peculiar and rather complicated version of the old horizontal skid type, and shock absorption was by oleo members, as on the F.K.3.
  Structurally, the F.K.8 had little to distinguish it, for it was a typical wire-braced biplane of wooden construction, but it had one feature which was uncommon in a British machine: namely, the use of inverted vee struts connecting the upper wings to the fuselage and the consequent absence of a centresection. Dual control was fitted: a small control column was provided on the starboard side of the observer’s cockpit, and was connected by an external link-rod to the starboard control arm from. which cables ran aft to the elevators. The observer thus had control over the elevators but not over the ailerons; and the rudder cables were provided with handgrips where they passed inside his cockpit, in order to give him emergency use of the rudder. The tailplane was adjustable, and was trimmed by a handwheel on the starboard side of the pilot’s cockpit.
  The F.K.8 was well-liked by its crews, who regarded it as being strong and easy to fly. By the end of 1917 Big Acks were leaving the Armstrong Whitworth works at a rate of more than eighty per month, and production continued until July, 1918.
  The final production version of the F.K.8 had the 160 h.p. Beardmore engine and retained the cleaner cowling, but improved radiators of reduced size were fitted, and on some machines a long horizontal exhaust pipe replaced the manifold with two short outlets which was more widely used. The most noticeable modification lay in the fitting of a plain vee undercarriage of more conventional design. As the illustrations show, two slightly different types of vee undercarriage were fitted.
  Other motors fitted experimentally to the F.K.8 were the 150 h.p. R.A.F. 4a and the 150 h.p. Lorraine-Dietrich, the latter installation being characterised by an enormous spinner on the airscrew and twin exhaust stacks. These exhaust stacks were large and had a pronounced backwards rake. Machines to which the R.A.F. 4a was fitted were B.214 and B.215, and A.2696 had the Lorraine-Dietrich.
  During the German offensive of March, 1918, the Big Acks did good work. On March 21st the machines of No. 35 Squadron dropped one hundred and sixteen 25-lb bombs and fired hundreds of rounds of ammunition on enemy troops and transport in the Maissemy area. They also directed artillery fire on to targets of massed infantry and cavalry with telling effect. Night bombing was another task allotted to the F.K.8s.
  It was during this German offensive that Second Lieutenant Alan A. McLeod of No. 2 Squadron won the Victoria Cross for the action fought by him and his observer, Lieutenant A. W. Hammond, M.C., on March 27th, 1918. These two officers of No. 2 Squadron were returning from a bombing raid when they were attacked by a Fokker Dr.I, Hammond promptly shot it down, but seven more Fokkers appeared and McLeod was wounded after destroying one of them. Hammond shot down two more, but was wounded six times, and the F.K.8 was so badly damaged that the floor of the rear cockpit fell out. Hammond was barely conscious and McLeod had five wounds when the petrol tank was hit and flames engulfed the front cockpit.
  Despite his wounds, McLeod climbed out on to the port wing and, with one hand on the burning control column, side-slipped to keep the flames away until the machine crashed in No-Man’s-Land. Hammond continued to fire at the remaining Fokkers until the crash knocked him unconscious. McLeod dragged him towards the British lines, receiving a sixth wound from a bomb-splinter while doing so. British troops rescued both airmen, who miraculously recovered from their terrible wounds, though Hammond suffered the amputation of one of his legs. Notification of the award of McLeod’s V.C. came through in due course, and Hammond received a bar to his M.C. McLeod was eighteen years old at the time.
  The Big Acks of No. 8 Squadron took part in experiments in cooperation with tanks in 1918, for which purpose the unit was attached to the Tank Corps on July tst, 1918. Officers of the squadron exchanged duties with officers of the tank units, and significant experiments were conducted with radio telephony as a means of communication between the air observers and the tank crews. The short range of the early R/T apparatus led to the substitution of wireless telegraphy at the end of July, but these experiments were too late for a procedure to be devised before the Armistice.
  It was an officer of No. 8 Squadron who won the second V.C. to be awarded to an F.K.8 pilot. On August 10th, 1918, Captain F. M. F. West, with Lieutenant J. A. G. Haslam as his observer, had dropped his bombs on an enemy gun position, and was still flying low when he was attacked by six enemy fighters.
  Their first burst of fire almost severed his left leg, and no sooner had he lifted his useless limb clear of the controls than he was hit again in the other leg. Although faint from loss of blood and half-dead with pain, West managed to keep the F.K.8 on an even keel while Haslam drove off the attackers. West eventually landed in the British lines and refused to go to hospital until he had given the Tank Commander a detailed report of the enemy concentration points.
  An unusual duty fell to the Big Acks of No. 35 Squadron on October 8th, 1918. It consisted of the maintaining of a smoke screen for two hours over the ground in front of the attacking British XIII Corps, west of Serain. The screen was produced and maintained by the continuous dropping of 40-lb phosphorus bombs by relays of aircraft.
  A few Armstrong Whitworth F.K.8s were used on Home Defence duties, and one of those belonging to No. 50 (Home Defence) Squadron shot down a Gotha into the sea near the North Foreland on July 7th, 1917. The crew of the Armstrong Whitworth were Second Lieutenant F. A. D. Grace and Second Lieutenant G. Murray.
  In Macedonia the F.K.8s of Nos. 17 and 47 Squadrons carried out many useful raids on enemy installations. One of the most notable of these raids was that made on Hudova aerodrome on May 23rd, 1918, when a ton of bombs was dropped. In September, 1918, No. 47 Squadron took part in an action which resembled one fought by No. 1 Squadron, Australian Flying Corps, in Palestine. On exactly the same date, September 21st, 1918, No. 47’s Big Acks and D.H.9s dropped 5,000 lb of high explosives and fired 1,200 rounds of ammunition into the retreating Bulgarian army in the Kosturino Pass, while on the Farweh road the Bristol Fighters of the Australian squadron took a dreadful toll of the retreating Turks caught, like the Bulgarians, in a valley: the Wadi el Far‘a.
  The F.K.8 did not survive long in the R.A.F. after the Armistice, and only eight went on the British Civil Register. In Australia, two F.K.8s pioneered air travel: they were used by the Queensland and Northern Territory Aerial Service Co., Ltd., on the company’s first regular service over the route Charleville-Longreach-Cloncurry which opened on November 2nd, 1922.


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Other Contractors: Angus Sanderson & Co., Newcastle-on-Tyne.
  Power: Standard: 120 h.p. Beardmore or 160 h.p. Beardmore. Experimental: 150 h.p. R.A.F. 4a and 150 h.p. Lorraine-Dietrich.

Weights (lb) and Performance:
Engine 120 h.p. Beardmore 160 h.p. Beardmore 150 h.p. R.A.F. 4a Lorraine-Dietrich
No. of Trial Report M.32 M.46 M.103 M.89
Date of Trial Report May, 1916 May, 1916 May, 1917 April, 1917
Type of airscrew used on trial L.P.920 - B. & C. 3120 L.P.3020 No. P. 1900
Weight empty 1,682 1,916 1,980 1,936
Military load 105 133 185 185
Crew 320 360 360 360
Fuel and oil 340 402 302 335
Weight loaded 2,447 2,811 2,827 2,816
Maximum speed (m.p.h.) at ground level - 98.4 - -
1,000 ft - - - -
2,000 ft - 97 - -
3,000 ft - - - 92
4,000 ft - 98 - -
5,000 ft - 97 - -
6,000 ft - 96 - -
6,500 ft - - 94 89
8,000 ft 83-5 93 - -
10,000 ft - 88 885 83
12,000 ft - 88 - -
m. s. m. s. m. s. m. s.
Climb to 1,000 ft - - 1 45 1 55 1 55
2,000 ft - - 3 50 - - - -
3,000 ft - - 6 00 - - - -
4,000 ft - - 8 10 - - - -
5,000 ft - - 11 00 - - - -
6,000 ft - - 13 55 - - - -
6,500 ft 19 00 15 25 16 25 16 30
7,000 ft - - - - - - 17 00
8,000 ft - - 20 05 - - - -
9,000 ft - - 23 49 - - - -
10,000 ft 35 00 27 5° 32 00 33 15
11,000 ft - - 32 20 - - 40 55
12,000 ft - - 39 00 46 25 - -
13,000 ft - - 49 00 57 10 - -
Service ceiling (feet) 12,000 13,000 15,000 13,000
Endurance (hours) 3 3 3 4
Tankage :
160 h.p. Beardmore R.A.F. 4a Lorraine-Dietrich
  Petrol 47 1/2 gallons 36 gallons 40 gallons
  Oil 4 3/4 gallons 6 gallons 5 gallons
  Water 6 gallons Nil 1 1/2 gallons
  Dimensions: Span: 43 ft 6 in. Length: (120 h.p. Beardmore) 30 ft 11 in.; (160 h.p. Beardmore) 31 ft; (R.A.F. 4a and Lorraine-Dietrich) 31 ft. Height: (120 h.p. Beardmore) 10 ft 11 in.; (160 h.p. Beardmore) 11ft; (R.A.F. 4a and Lorraine-Dietrich) 11 ft 3 in. Chord: 6 ft 6-7 in. Gap: (160 h.p. Beardmore) 5 ft 10-9 in.; (R.A.F. 4a) 5 ft 6 in.; (Lorraine-Dietrich) 5 ft 7 in. Stagger: (Beardmore and R.A.F. engines) 1 ft 7 3/4 in. at inner struts, 1 ft 7 11/16 in. at outer struts; (Lorraine-Dietrich) 1 ft 4 in. Dihedral: upper 3° 30', lower 2° 30'. Incidence: 2°. Span of tail: 13 ft 6 in. Wheel track: 6 ft. Tyres: 700 X 100 mm. Airscrew diameter: (160 h.p. Beardmore) 9 ft 3-8 in.; (R.A.F.) 9 ft 10 in.; (Lorraine-Dietrich) 8 ft 6 in.
Areas: Wings: 540 sq ft. Ailerons: each 17sq ft, total 68 sq ft. Tailplane:. 31 sq ft. Elevators: 26 sq ft. Fin: 10 sq ft. Rudder: 18 sq ft.
  Armament: One fixed, forward-firing Vickers machine-gun mounted under the cowling and synchronised to fire through the airscrew; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Service Use: Western Front: R.F.C. Squadrons Nos. 2, 8, 10, 35 and 82. H.Q. Communication Squadron. Home Defence: No. 50 Squadron. Macedonia: Part of No. 17 Squadron (the unit had nine F.K.8s on November 11 th, 1918); part of No. 47 Squadron (ten F.K.8s on November nth, 1918). Palestine: Part of No. 142 Squadron (seven F.K.8s on September 19th, 1918). Training: W/T Telegraphist School, Chattis Hill; School of Army Cooperation, Winchester; School of Photography, Maps and Reconnaissance, Farnborough; Air Observers’ Schools at Hythe, New Romney, Manston and Eastchurch; No. 4 School of Aerial Gunnery, Marske; Advanced Air Gunnery School, Lympne; No. 1 Training Depot Squadron, Stamford; No. 31 Training Squadron, Wyton; No. 39 Training Squadron, Narborough.
  Production and Allocation: For the reasons given under this heading in the history of the Armstrong Whitworth F.K.3 precise figures are not available. A total of 1,596 Armstrong Whitworths of both types were delivered to the R.F.C., of which 777 went to the Expeditionary Force in France, 205 to the Middle East Brigade, eight to Home Defence units, and the remainder to Training Units.
  On October 31st, 1918, 694 Armstrong Whitworth F.K.8s were on charge with the R.A.F. Of these, 182 were in France, twenty-one were en route to the Middle East, fifty-six were in Egypt and Palestine, forty-four were in Macedonia, and two were on the North-West Frontier of India. At home, 263 were in store, twenty-one were in transit to or at Aeroplane Repair Depots, thirty-six were at Aircraft Acceptance Parks or with contractors, sixty-six were at training units and various other aerodromes, and three were at experimental stations.
  Serial Numbers: A.2683-A.2732: built by Armstrong Whitworth under Contract No. 87/A/508. A.9980-A.9999. B.201-B.330: built by Armstrong Whitworth under Contract No. 87/A/508. B.3301-B.3400: built by Armstrong Whitworth. B.4120, B.4165, B.4176, B.4200: rebuilds by No. 2 (Northern) Aeroplane Repair Depot. B.5751-B.5850: built by Armstrong Whitworth. G.3507-G.3706: built by Angus Sanderson. C.8401-8650: built by Armstrong Whitworth. D.5001-D.5200: built by Armstrong Whitworth. F.623. F.638, F.4231 (possible batch F.4221-F.4270). F.7384, F.7484. H.4473, H.4561, H.4573, H.4585, H.4612.
  Notes on Individual Machines: Used by No. 2 Squadron: A.9998, B.218, B.246 (Aircraft “13”), B.248, B.258, B.288, B.315. Used by No. 10 Squadron: B.250, B.271, B.324, B.325, B.5772. Used at No. 1 Training Depot Squadron, Stamford: B.4120, B.4165, C.8548, C.8577, D.5075. Other machines: A.2696: fitted with 150 h.p. Lorraine-Dietrich engine No. 1018. B.214 and B.215: fitted with R.A.F. 4a engine. B.252: used at Marske. B.320: No. 50 Squadron. B.3326: used at A.A.G.S. Lympne. C.3648: No. 3 Training Squadron. C.8468: No. 3 Training Squadron. D.5150: became G-EAET. H.4473: became G-EAIC. H.4561: became G-AUCF. H.4573: became G-EAVT. H.4585: became G-EAVQ. H.4612: became G-EAJS.
  Costs:
   Airframe without engine, instruments or armament £1,365 17s. €825 os.
   Engines:
   120 h.p. Beardmore £825 0s
   160 h.p. Beardmore £1,045 0s
   150 h.p. R.A.F. 4a £826 0s.

Armstrong Whitworth F.M.4, the Armadillo

  IN 1917, Frederick Koolhoven left Armstrong Whitworth to become chief designer to the newly-formed B.A.T. Co., and responsibility for design work at Gosforth fell upon Mr F. Murphy. In the summer of 1918 there emerged from the Armstrong Whitworth works a heavy-shouldered, pugnacious-looking biplane named the Armadillo.
  This was a small single-seat fighter which was test-flown in September, 1918. The fuselage was basically a simple wooden box-girder cross-braced in the usual fashion, and it completely filled the gap between the mainplanes; the upper wing was attached to the fuselage and had no conventional centresection. The forward portion of the fuselage was reinforced by duralumin girders of channel section, to which the petrol and oil tanks and the pilot’s seat were attached; and the sides of the fuselage were strengthened with a covering of three-ply.
  The armament consisted of two fixed Vickers machine-guns, installed in the hump which faired the engine cowling up to the level of the upper wing. The original design included an additional Lewis gun mounted on the upper starboard wing root, firing forwards and upwards over the airscrew. It is not surprising that this third gun was not in fact fitted.
  The undercarriage depended for shock absorption on rubber cord, but in its installation an interesting departure from the practice of the time was made. Instead of simply binding the axle to the apices of the vee-struts, a loop of elastic cord was attached to the fuselage at the top of each vee; from the lower end of each loop a steel cable ran down the inside of the fairings of the vee-struts, around a small pulley at the bottom of the vee, and then over the axle. Thus, any upward movement of the axle tensioned the cable and extended the rubber cord. The undercarriage underwent slight modification, and later had sturdier-looking legs.
  The Armadillo came upon the wartime scene rather too late to be considered for development or production, but it seems doubtful whether it would have proved popular with pilots, for the view from the cockpit was poor in a forward and downward direction. From his position immediately behind the trailing edge of the upper wing the pilot had a fine view of the entire upper hemisphere, but for landing or ground attack work his view was severely limited by the bulky forward fuselage and engine cowling, and by the wings. Both wings were cut away at the roots, and an aperture was cut in the port side of the fuselage in front of the cockpit in an endeavour to improve the pilot’s view.
  With the Armistice the Armadillo faded away, but no doubt the machine provided useful data for the design of its successor, the Ara.


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Power: 230 h.p. Bentley B.R.2 rotary engine.
  Dimensions: Span: 27 ft 9 in. Length: 18 ft 10 in. Height: 7 ft 10 in. Chord: upper 5 ft 3 in., lower 4 ft 6 in. Gap: 3 ft 11 in. Stagger: 8 1/2 in. Dihedral: upper nil, lower 2°. Incidence: upper 2° 15', lower 1°. Span of tail: 11 ft 2 in.
  Areas: Wings: 232 sq ft. Total aileron area: 36 sq ft. Tailplane: 17 sq ft. Elevators: 14 sq ft. Fin: 1-6 sq ft. Rudder: 6 sq ft.
  Weights: Empty: 1,250 lb. Loaded: 1,860 lb.
  Performance: Maximum speed at ground level: 125 m.p.h.; at 10,000 ft: 113 m.p.h. Climb to 10,000 ft: 6 min 30 sec. Ceiling: 24,000 ft. Endurance: 2 3/4 hours.
  Tankage: Main fuel tank: 26 gallons. Auxiliary: 14 gallons. Total: 40 gallons.
  Armament: Two fixed Vickers machine-guns mounted within the fuselage and above the engine, synchronised to fire forward through the airscrew.
  Serial Number: X.19, built under Licence No. 18.

Armstrong Whitworth Ara

  THE Ara did not appear until early in 1919, but it was a late wartime design, as serial numbers indicate, and as such it merits a place in this history. It was roughly contemporary with the Sopwith Snapper and Nieuport Nighthawk, and was built to much the same formula.
  The Ara was designed by F. Murphy and, as might be expected, bore a family resemblance to the Armadillo. The likeness was particularly apparent in the disposition of the interplane struts and the shape of the vertical tail surfaces. The pilot’s view was better than that afforded by the Armadillo: the use of a conventional upper centre section raised the upper wing above the fuselage to the level of the pilot’s eyes. On the first Ara, F.4971, the lower wing was attached directly to the fuselage, but the second machine had increased gap and the fuselage was mounted between the wings in a manner reminiscent of the Bristol Fighter.
  The fuselage lines were commendably clean, and the fairing of the nose and engine installation was particularly noteworthy. The good aerodynamics of the design were reflected in the excellent performance.
  Like so many other good aeroplanes of its time, the Ara arrived too late; and its fate was sealed by the closing of the aircraft department of Sir W. G. Armstrong, Whitworth & Co., Ltd., late in 1919. There can be little doubt that the erratic behaviour of the A.B.C. Dragonfly engine must have detracted greatly from the aircraft’s capabilities and would, in any case, have discouraged further development of the design. (The A.B.C. Dragonfly is discussed at some length in the history of the Nieuport Nighthawk.)


SPECIFICATION
  Manufacturers: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne.
  Power: 320 h.p. A.B.C. Dragonfly radial engine.
  Dimensions: Span: 27 ft 5 in. Length: 20 ft 3 in. Height: 7 ft 10 in. Chord: upper 5 ft 3 in., lower 4 ft 6 in. Gap: 3 ft 10 1/2 in. Stagger: 11 1/2 in. Dihedral: 1° 30'. Incidence: upper 2° 45', lower 1° 15'.
  Areas: Wings: upper 147 sq ft, lower 110 sq ft, total 257 sq ft. Total aileron area: 20-4 sq ft. Tailplane: 25 sq ft. Elevators: 24 sq ft. Fin: 2-5 sq ft. Rudder: 11 sq ft.
  Weights: Empty: 1,320 lb. Loaded: 1,930 lb.
  Performance: Maximum speed at ground level: 150 m.p.h.; at 10,000 ft: 145 m.p.h. Climb to 10,000 ft: 4 min 30 sec. Ceiling 28,000 ft. Endurance: 3 1/4 hours.
  Armament: Two Vickers machine-guns mounted low down inside the fuselage and firing between the lowest pair of cylinders of the engine on either side. The guns were synchronised to fire forward through the revolving airscrew.
  Serial Numbers: F. 4971-F. 4973.

Siddeley S.R.2, the Siskin

  IT would be almost true to say that the Siskin missed being the S.E.7 only because of the recommendations of the Burbidge Committee. The first rough outlines were sketched by Major F. M. Green shortly before he left the Royal Aircraft Factory to join the Siddeley-Deasy company. The original concept envisaged the use of the 300 h.p. R.A.F. 8 engine, a fourteen-cylinder two-row radial which was designed in September, 1916.
  However, the real design work was done at the Siddeley-Deasy works, and it could fairly be claimed that the Siskin was the first all-Siddeley design. In common with such contemporaries as the Ara, Basilisk, Nighthawk, Snapper and Snark, the Siskin was not completed until 1919: it appeared in the summer of that year and underwent its official trials in July. Like those single-seaters, too, the Siskin was powered by the 320 h.p. A.B.C. Dragonfly I radial engine.
In the Siskin great care was taken to make the engine installation as clean as possible; a blunt spinner was fitted, and the engine cowling blended harmoniously with it. The airframe was predominantly a wooden structure. The basic fuselage box-girder had faired sides as far back as the cockpit and a rounded top-decking throughout its length. The pilot sat fairly high. The mainplanes were of unequal span and chord, and were characterised by centre-section bracing reminiscent of that of the Sopwith 1 1/2-Strutter, outwards-raked interplane struts, and raked tips. The tail-unit was of characteristic shape, yet embodied features that were to be seen in the S.E.5, R.E.8, and R.E.9, and also bore a certain resemblance to that of the Austin Greyhound. The undercarriage was of distinctive design: shock absorption was by means of the main single oleo legs, the lower ends of which were linked by radius-rods to the apices of a pair of vee-struts a short way aft.
  The Siskin did not go into production in its original form, doubtless because of its Dragonfly engine. Yet with that engine it had a better performance than most of its contemporaries, and was one of the sweetest-natured of aeroplanes. It flew at the R.A.F. Pageant in 1920, when it was obliged to bring off a hurried forced-landing because of engine failure.
  In view of its war-time origin, it is not without interest to trace the history of the Siskin’s later power unit, the Armstrong Siddeley Jaguar engine.
  As related above, a fourteen-cylinder radial engine of 1,374 cu in. displacement was designed at the Royal Aircraft Factory in September, 1916. The new engine design was named R.A.F. 8 but was not built at Farnborough.
  When Major F. M. Green joined the Siddeley-Deasy Motor Car Co., Ltd., early in 1917, his immediate responsibility was the development of the 230 h.p. B.H.P. engine. He asked for and obtained permission to develop the R.A.F. 8 engine, and put S. D. Heron in charge of the design work.
  On April 5th, 1917, the Air Board issued a specification for a new aircraft engine. The specification, known as Scheme A, had been inspired by the Admiralty, and called for a radial engine of not more than 42 inches diameter capable of developing at least 300 h.p. This specification might have been that of the R.A.F. 8 itself, and J. D. Siddeley submitted the design to the Air Board. The engine which won an official contract was the Cosmos Mercury; nevertheless, Siddeley continued the development of the R.A.F. 8, and the name Jaguar was given to the new engine.
  Cylinder design was by S. D. Heron, and the engine was the first to have an all-aluminium head with two valves inclined at a large angle to each other; this design feature was to be found in radial engines several decades later. J. D. Siddeley ordered the construction of the cylinders to be made similar to that of the Puma but when, in the middle of 1917, he instructed Heron to fit a new cylinder head with three valves, Heron resigned rather than do so.
  Thereafter Jaguar development lagged for about two years. After the A.B.C. Dragonfly was proved to be a failure, Siddeley received a Government order for the Jaguar. Development was resumed by S. M. Viale, who re-designed several parts of the engine. J. D. Siddeley decided to remove the supercharger in order to simplify development of the basic design, and by the middle of 1920 the Jaguar was running quite well. In June 1922, by which time the stroke had been increased from 5 inches to 5 1/2 inches, the Jaguar passed the official Air Ministry type test and was ordered in quantities.
  The original Siddeley Siskin ultimately fulfilled its first conception, for it was fitted with an early Jaguar engine in place of the erratic Dragonfly. The airframe design was subsequently considerably modified and, as the Armstrong Whitworth Siskin, equipped several R.A.F. fighter squadrons and appeared in other forms.


SPECIFICATION
  Manufacturers: The Siddeley-Deasy Motor Car Co., Ltd., Park Side, Coventry.
  Power: 320 h.p. A.B.C. Dragonfly I.
  Dimensions: Span: upper 27 ft 6 in. Length: 21 ft 3 in. Height: 9 ft 9 in.
  Areas: Wings: 247 sq ft.
  Weights and Performance: No. of Trial Report: M.260. Date of Trial Report: July, 1919. Type of airscrew used on trial: A.B.8979. Weight empty: 1,463 lb. Military load: 218 lb. Pilot: 180 lb. Fuel and oil: 320 lb. Loaded: 2,181 lb. Maximum speed at 6,500 ft: 145 m.p.h.; at 10,000 ft: 143-5 m.p.h.; at 15,000 ft: 139 m.p.h. Climb to 6,500 ft: 4 min 30 sec; to 10,000 ft: 7 min 50 sec; to 15,000 ft: 13 min 50 sec. Service ceiling: 23,800 ft.
  Armament: Two fixed and synchronised Vickers machine-guns mounted on top of the fuselage, firing forward.
  Serial Numbers: C.4541-C.4546.

Austin-Ball A.F.B.1.

  THE Austin-Ball A.F.B.1 was a single-seat fighting scout designed to the ideas of Captain Albert Ball, V.C., D.S.O., M.C., and represented his conception of the ideal single-seat fighter. At the beginning of April, 1916, Ball wrote home in the following enthusiastic terms:
  “I have the plans now of a most wonderful machine. It will be heaps better than the Hun Fokker. I have been to the Major and he has given me full permission to fly it if I can get one out. I know that it will be a fine thing.”
  On his first leave, Ball took the plans home with him and spent the winter of 1916-17 in trying to arrange for the construction of the machine, which was to be made by the Austin Motor Company. Early in 1917, while in London, Ball met a representative of the firm who was greatly discouraged at having failed to interest the Air Board in the Austin-Ball Scout. Ball went straight to Brigadier-General Sefton Brancker, then Director of Air Organisation, and made such strong representations that he came away with an order to build two machines at once and the promise that, if they were built in time and proved to be successful, a large production order would be placed.
  The Austin-Ball A.F.B. 1 was characterised by an unusually deep fuselage which almost completely filled the gap between the mainplanes. The upper mainplane was at the level of the pilot’s eyes and he therefore had an excellent view all round the upper hemisphere. The mainplanes were swept back slightly, but were rigged with neither stagger nor dihedral. No fixed fin was fitted; and the rudder, of a pleasing oval shape, looked surprisingly small. The A.F.B.i was a thoroughly workmanlike aeroplane in every way, and its most remarkable feature lay in the disposition of its armament.
  Ball gained most of his victories while flying a Nieuport Scout, and one of his favourite methods of attack was to stalk his victim from behind and below, gradually coming up under his enemy’s blind spot. Once in the position he favoured, Ball would let down his Lewis gun to the lower limit of its travel on the rail of its Foster mounting, and a short no-deflection burst of fire sufficed to despatch the enemy machine. It was, of course, a simple matter for Ball to rake the victim from nose to tail by a small back-and-forward movement of the stick. He used this same form of attack when he later flew S.E.5s.
  It comes as no surprise, therefore, to learn that one of the Austin-Ball Scout’s Lewis guns was fitted to a Foster mounting on the upper wing. As on the Nieuport, this Lewis was mounted at an angle above the horizontal. But the installation of the A.F.B. 1’s other Lewis gun represented a radical departure from contemporary practice, for it was arranged to fire forward through the hollow airscrew shaft in the manner of latter-day moteurs-canons.
  This may well have been the first instance of this particular method of mounting an aeroplane weapon, and was a commendable attempt to provide a gun on a tractor aeroplane firing forward along the line of flight. If Ball had the plans of the machine in April, 1916, it must have been designed some time before that date. The first British aeroplane fitted with a gun synchronising gear (a Bristol Scout with the Vickers mechanical gear) reached France only on March 25th, 1916; but whether the A.F.B.1’s armament installation was designed in ignorance of the existence of a British interrupter gear, or simply to avoid the use of such a gear, will probably never be known. It may well be that Ball preferred the Lewis to the Vickers gun: the Lewis, although a simpler weapon mechanically, was less well suited to firing with synchronising or interrupter gears. In the A.F.B.1 the breech of the lower Lewis gun projected backwards into the cockpit, where it was ideally accessible for reloading and stoppage-clearance.
  Owing to the delays experienced in the machine’s design stages, it was not until July, 1917, two months after Ball’s death, that the A.F.B.1 was ready for testing. By that time the S.E.5 and Sopwith Camel were well into large-scale production and in squadron service in ever-increasing numbers. The A.F.B.1’s performance was startling, and it was described as comfortable to handle although its lateral control could have been better. However, the Air Board did not consider its superiority over the machines then in production to be great enough to justify interference with existing production plans, and the type was not developed further.


SPECIFICATION
  Manufacturers: The Austin Motor Co. (1914), Ltd., Northfield, Birmingham.
  Power: 200 h.p. Hispano-Suiza. Engines Nos. W.D.8302 and W.D.8354 were fitted.
  Dimensions: Span: 30 ft. Length: 21 ft 6 in. Height: 9 ft 3 in. Chord: 5 ft. Gap: 4 ft 9 in. Stagger: nil. Dihedral: nil. Incidence: 2°. Span of tail: 11 ft 3 in. Tyres: 700 X 75 mm. Airscrew: (i) Grahame-White No. 512 - diameter 9 ft 6 in., pitch 7 ft 3 in. (ii) Tibbenham T.28097, No. 4205 - diameter 7 ft 9 in., pitch 10 ft 6 in. (iii) Vickers Series No. 192 - diameter 8 ft.
  Areas: Wings: 290 sq ft. Ailerons: each 7-5 sq ft, total 30 sq ft. Tailplane: 16 sq ft. Elevators: 16 sq ft. Rudder: 8 sq ft.
  Weights: Empty (with water): 1,525 lb. Military load: 87 lb. Pilot: 180 lb. Fuel and oil: 285 lb. Loaded: 2,077 lb.

Performance: No. of Trial Report M.122 M.122 M.122
Date of Trial Report July, 1917 July, 1917 July, 1917
Maximum speed (m.p.h.)
at ground level 138 - -
6,500 ft - 119 -
10,000 ft 126'5 115'5 118
12,000 ft 124 - -
13,000 ft 123 112 -
15,000 ft 120'5 - -
16,500 ft 118'5 - -
19,000 ft 114-5 - -
m. s. m. s. m. s.
Climb to
1,000 ft 0 40 - - - -
6,000 ft 4 45 - - - -
6,500 ft - - 8 25 6 35
10,000 ft 8 55 15 15 11 45
14,000 ft 14 30 - - - -
18,000 ft 23 00 - - - -
20,000 ft 29 55 - - - -
Service ceiling (feet) 22,000 16,000 17,000
Endurance 2 1/4 hours at full speed at 10,000 ft
Tankage:
   Petrol:
   Top (pressure) tank 9 gallons
   Bottom (pressure) tank 20 gallons
   Service (gravity) tank 3 gallons
   Total 32 gallons
Oil 5 gallons
Water 9 gallons
  Armament: Two Lewis machine-guns, one fixed to fire forwards through the hollow airscrew shaft, the other on a Foster mounting above the upper wing firing forwards and upwards over the airscrew.
  Production: Two Austin-Ball A.F.B.1s were ordered under Contract No. 87/A/1524, but it is uncertain whether the second machine was completed.

Austin A.F.T.3, the Osprey

  THIS rather corpulent triplane was designed in 1917 to meet the requirements of the official specification A. 1A and was flown early in 1918. It was tested at Martlesham Heath in March of that year.
  In construction the Austin A.F.T.3 was typical of the period, and was almost wholly made of wood. The fuselage was a wire-braced wooden box-girder with a rounded top-decking and fairings behind the engine-cowling. Particular care was devoted to detail design with a view to simplification of production and ease of maintenance in the field: only two patterns of fittings for the fuselage spacers were used, and any longeron could be replaced without disturbing the cross-bracing. All mainplanes on each side were interchangeable, as also were the ailerons.
  The undercarriage was sprung in an unorthodox fashion. A special shock-absorber was mounted centrally under the spreader-bar, and from its sides cables ran to the apices of the undercarriage vees where they passed over pulleys and were connected to the ends of the axle. Thus any upward deflection of the axle extended the rubber cord within the shock-absorber.
  The rudder was a plain balanced surface, and it was braced to the rear spar of the tailplane by cables which ran from the top of its axis. The incidence of the tailplane could be adjusted in flight.
  It seems probable that the Austin Osprey was a competitor of the Sopwith Snipe. Its performance was quite good and it must have been manoeuvrable, but the triplane configuration imposed penalties of drag and made rigging rather more complicated. The Snipe was officially adopted, and the Austin triplane was not further developed. It was, however, flown well into the summer of 1918.


SPECIFICATION
  Manufacturers: The Austin Motor Co. (1914), Ltd., Northfield, Birmingham.
  Power: 230 h.p. Bentley B.R.2 rotary engine; engine No. E.X.3.
  Dimensions: Span: 23 ft. Length: 17 ft 7 in. Height: 10 ft 8 in. Chord: 3 ft 8 1/2 in. Gap: upper 3 ft 1 1/2 in., lower 3 ft 6 1/2 in. Stagger: 2 ft 2 in. Dihedral: 30. Incidence: 30. Span of tail: 8 ft 2 1/2 in.
  Areas: Wings: 233 sq ft. Ailerons: each 5-33 sq ft, total 32 sq ft. Tailplane: 23-4 sq ft. Elevators: 23-4 sq ft. Rudder: 5-5 sq ft.
  Weights: Empty: 1,106 lb. Military load: 291 lb. Pilot: 180 lb. Fuel and oil: 311 lb. Loaded: 1,888 lb. Performance: No. of Trial Report: M.189. Date of Trial Report: March, 1918. Type of airscrew used on trial: Lang 4040. Maximum speed at 10,000 ft: 118-5 m.p.h.; at 15,000 ft: 110-5 m.p.h. Climb to 6,500 ft: 5 min 30 sec; to 10,000 ft: 10 min 20 sec; to 15,000 ft: 21 min 20 sec. Service ceiling: 19,000 ft. Endurance: 3 hours at 15,000 ft.
  Tankage: Petrol: main (gravity) tank 26 gallons, service tank 14 gallons, total 40 gallons.
  Armament: There were two fixed and synchronised Vickers machine-guns mounted on top of the fuselage, firing forwards; and at one time a Lewis machine-gun was fitted on the steel tube spars of the middle centre section.
  Serial Number: X.15, built under Licence No. 17.

Austin Greyhound

  THE Greyhound was the last military aircraft to be designed and built by the Austin Motor Co. during the 1914-18 war. It was a handsome two-seat two-bay biplane, intended to replace the Bristol Fighter as a fighter-reconnaissance type; and it represented an attempt to provide the performance and equipment considered necessary after the experience of four years of war.
  The lines of the fuselage reflected a compromise between comparative simplicity of structure and aerodynamic and operational efficiency, based on the usual contemporary method of construction. The pilot sat fairly high and directly under a large cut-out in the trailing edge of the centre section, and his downward view was helped by the narrow chord of the lower wings. The observer was immediately behind the pilot, as in the Bristol Fighter, and had an excellent field of fire for his Lewis gun.
  The equipment of the Greyhound included a camera, wireless, oxygen and heating apparatus. Its performance was by no means bad, and it seems a pity that this interesting type was not further developed. In common with so many of its contemporaries, of course, it suffered from the temperamental nature of its A.B.C. Dragonfly radial engine. If it had gone into production it would have required a different power unit, but it seems that no attempt was made to develop the Greyhound in any way after the failure of the Dragonfly engine. (The story of the A.B.C. Dragonfly is related in the history of the Nieuport Nighthawk).


SPECIFICATION
  Manufacturers: The Austin Motor Co. (1914), Ltd., Northfield, Birmingham.
  Power: 320 h.p. A.B.C. Dragonfly I.
  Dimensions: Span: upper 39 ft, lower 36 ft 7 in. Length: 26 ft 8 1/2 in. Height: 10 ft 4 in. Chord: upper 6 ft 4-8 in., lower 4 ft 3 in. Gap: 4 ft 11 7/8 in. Span of tailplane: 12 ft 9 5 in.
  Areas: Wings: 400 sq ft. Ailerons: each upper 14-8 sq ft, each lower 7-8 sq ft, total 45 2 sq ft. Tailplane: 27-2 sq ft. Elevators: 19-8 sq ft. Fin: upper 2-76 sq ft, lower 2-3 sq ft, total 5-06 sq ft. Rudder: 9-9 sq ft.
  Weights: Empty: 1,838 lb. Military load: 324 lb. Crew: 360 lb. Fuel and oil: 510 lb. Loaded: 3,032 lb.
  Performance: Maximum speed at 6,500 ft: 129 m.p.h., at 10,000 ft: 126 m.p.h., at 15,000ft: 121 m.p.h. Climb to 6,500 ft: 6 min 20 sec, to 10,000 ft: 10 min 50 sec, to 15,000 ft: 19 min 40 sec. Service ceiling: 22,000 ft. Endurance: 3 hours.
  Tankage: Petrol: 66 gallons. Oil: 8 gallons.
  Armament: Two fixed, synchronised Vickers machine-guns firing forwards; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Serial Numbers: H.4317-H.4319.

Avro 500

  ALTHOUGH the part played by the Avro 500 in the 1914-18 war was a small one, it was an aeroplane of historical importance for it was one of the first machines to be ordered for the use of the British Army. The order was placed by the Government early in 1912, and was for three two-seat biplanes fitted with 50 h.p. Gnome engines.
  Before the Gnome-powered Avros appeared, A. V. Roe completed a two-seat biplane with 60 h.p. E.N.V. engine, and this aircraft provided the basis for the military type. The Avro biplane with the Gnome engine was originally known as the Avro Biplane Type E, but some time later it was given the first of a new series of Avro type numbers which has continued until the present day. To quote Sir Alliott Verdon-Roe, as “a piece of drawing-office swank” the type number 500 was chosen as the beginning of the series.
  The Avro 500 bore quite a strong resemblance to its E.N.V.-powered predecessor. It was an equal-span two-bay biplane with warping wings, and was of wooden construction. The undercarriage, like that of the biplane with the E.N.V. engine, was an unusual structure which recalled the arrangement on contemporary Nieuport monoplanes. The wheels were mounted on the ends of a transverse leaf spring which was attached to a sturdy central skid. There was no tailskid; instead, the machine rested on the bottom of the rudder, which was suitably shod. This arrangement was obviously a somewhat dangerous one, and a modified rudder was later fitted. The new rudder still acted as tailskid, but had a certain amount of vertical travel against the compression of a coil spring in order to provide a measure of shock absorption.
  The first of the Avro 500s was in service in May, 1912, and when the Central Flying School of the R.F.C. was opened at Upavon on August 17 th of that year its equipment included two Avro 500s. Several of these Avro biplanes were used at the C.F.S., and the type was used in both the Naval and Military Wings of the early R.F.C. The original order was increased to twelve machines, and the contract enabled the firm of A. V. Roe & Co. to be soundly established.
  A late refinement was the fitting of a comma-shaped rudder similar to that of the later Avro 504. This rudder was fitted with a proper tailskid. The shape of the skids below the wing-tips varied: some Avro 500s had half-hoops; others had simple braced skids which, in some cases, were fitted with two tiny wheels.
  A single-seat version of the type also existed. It had a slightly longer decking on top of the nose portion of the fuselage. It may have been this version of the design which was known to the R.F.C. as the Avro Type Es.
  The Avro 500 was also built for several private owners, and one at least had inversely tapered ailerons in place of wing-warping. It was owned by J. L. Hall.
  By the time of the outbreak of hostilities in 1914 only a few Avro 500s survived, and they were used for training purposes. Perhaps the last was the one which survived at Chingford until August nth, 1915, when it was wrecked. This machine was fitted with a 100 h.p. Gnome fourteen-cylinder two-row rotary engine, an installation which was probably “home-made”.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Brownsfield Mills, Manchester.
  Power: 50 h.p. Gnome. At least one installation of a 100 h.p. Gnome was made.
  Dimensions: Span: 36 ft. Length: 29 ft. Airscrew diameter: 9 ft.
  Areas: Wings: 335 sq ft.
  Weights; Empty: 900 lb. Loaded: 1,300 lb.
  Performance: Maximum speed: 62 m.p.h.
  Service Use: Flown by No. 3 Squadron R.F.C. and at the Central Flying School before the war. Was used as a trainer in the early months of the war; e.g. at Chingford.
  Serial Numbers: 41, 51-53, 94, 150, 285, 288-291, 404-406, 430, 432, 433, 448.

Avro 503

  THE Avro company produced their first seaplane type in May, 1913. It was a large tractor biplane, powered by a 100 h.p. Gnome fourteen-cylinder engine, and was originally known as the Avro Type H. Later, the type number 503 was bestowed upon the aircraft.
  A. V. Roe & Co. were not without some experience in the construction of seaplanes, for an Avro tractor biplane had been used in 1911 by Commander Oliver Schwann m his experiments, aimed at producing a seaplane, which were conducted at Barrow-in-Furness. The company also built the airframe of the Waterbird Curtiss-type biplane for the Lakes Flying Co.
  The Avro 503 bore a certain resemblance to the Avro 500, particularly in the shape of its fuselage and tail unit. The upper wing was of slightly greater span than the lower, and was fitted with inversely-tapered ailerons. The main floats were single-step pontoon-type structures, covered with rubber-proofed cloth and sprung internally by rubber cord. The tail float was attached to the bottom of the rudder and moved bodily with it - an interesting analogy to the use of the base of the Avro 500’s rudder as a tail-skid.
  The test-flying of the Avro 503 was carried out at Shoreham by F. P. Raynham, assisted by John Alcock.
  A few examples of the type were built, and one was sold to Germany. Piloted by Leutnant Langfeld, this aircraft was the first to fly from the German mainland to Heligoland; the flight, with a passenger, was accomplished on September 6th, 1913.
  The Germans must have thought highly of the Avro 503, for the Gotha WD.1 seaplane which first appeared in February, 1914, was an unashamed copy of the Avro. In a German description published in June, 1919, the Gotha WD.1’s sprung floats and tail-high floating attitude were hailed as innovations, but no mention was made of their British origin. Whereas the Avro company built few other seaplanes, the Gotha concern developed a long series of successful floatplanes from the WD.1.
  The Avro 503 was also supplied in small numbers to the R.N.A.S. At least one was sent to the Isle of Grain for assembly; there it was test-flown and handed over to Commander J. W. Seddon. It is believed that this seaplane later participated in a bombing attack on Zeebrugge.
  The ultimate fate of that Avro 503 is unknown, and it is uncertain how many aeroplanes of the type were supplied to the R.N.A.S. At Eastchurch an Avro 503 was flown with a wheel undercarriage, and was used there for training purposes. This aircraft had bracing struts on the overhanging portions of the upper wings, and was fitted with enlarged ailerons.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Brownsfield Mills, Manchester.
  Power: 100 h.p. Gnome.
  Dimensions: Span: upper 50 ft, lower 47 ft. Length: 33 ft 6 in. Chord: 6 ft.
  Areas: Wings: 567 sq ft.
  Weights: Loaded: about 2,200 lb.
  Service Use: R.N.A.S., Eastchurch. Serial Numbers'. 16.

Avro 504

  ALTHOUGH it performed few resounding feats of arms, the Avro 504 in its great variety of forms is assured of a place of honour in our aircraft history. Whether it is remembered as a delightful trainer of the war period or as a friendly aeroplane popping into and out of improbable fields as a joy-riding machine in the inter-war years, its immortality is secure. Above all, it was the aircraft which helped to lay the foundations of decades of safe and logical flying instruction.
  The Avro 504 was more closely related to the Avro 500 than to any other preceding Avro type. Construction of the first 504 was begun in April, 1913, and its first tests were carried out at Brooklands in July of that year. The machine made its debut at Hendon on September 20th, 1913, as an entrant in the second Aerial Derby.
  When the prototype Avro 504 first appeared, it had the 80 h.p. Gnome rotary engine installed in a nose-bearing mounting and within a cowling of square cross-section; the cowling had an arched top and bulged sides. The fuselage was a typical wire-braced wooden box-girder with the upper longerons quite straight in side elevation. The fuselage terminated in a vertical stern-post to which was attached a comma-shaped rudder; there was no fin, and the tailskid was attached directly to the bottom of the rudder. The main undercarriage was an original variation on the wheels-and-skid theme. There was a long central skid, and each main undercarriage leg carried its own shock absorber encased in a fairing. Each shock absorber consisted of 8 ft 8 in. of rubber cord in tension. The two-bay wings were of equal span and had a pronounced stagger. Each wing panel had only five fully formed ribs, which also served as compression members. Light spanwise stringers were let into these ribs, and the remaining contour-forming ribs consisted of strips of wood which were fastened to the leading edge, spars, stringers, and trailing edge. Lateral control was obtained by the curious device of warping ailerons. Although separate surfaces, these ailerons were secured at their inboard ends; they were inversely tapered, and their broad outer ends were warped by means of cables. Upper and lower ailerons were connected by a strut.
  It was at once obvious that, with the possible exception of the warping ailerons, the Avro 504 was a thoroughly workmanlike aeroplane and considerably in advance of most of its contemporaries in design, construction and performance.
  Much of the early flying of the 504 was done by F. P. Raynham. Flown by him, the machine was placed fourth in the second Aerial Derby at an average speed of 66.5 m.p.h.
  Another contest in which the prototype 504 took part, again flown by Raynham, was the so-called “War of the Roses” contest, flown off on October and, 1913. In this, the Avro firm had accepted a challenge to a cross-country race against Dr Christie’s new Blackburn monoplane, flown by Harold Blackburn. A trophy was provided by the Yorkshire Evening News, and the course was Leeds-York-Doncaster-Sheffield- Barnsley-Leeds, a total distance of 100 miles. Visibility was very bad, and Raynham, who was over completely strange territory, had to abandon the race when near Barnsley.
  The Avro 504 underwent certain modifications early in its career. The engine was given a new nose-bearing support made of bent steel tubing, over which was fitted a new cowling of rather bulbous appearance but better streamline form. Lateral control with the warping ailerons was not particularly effective, so freely-hinged conventional ailerons of constant chord replaced the original warping controls.
  On November 24th, 1913, Raynham flew the machine to Farnborough to undergo official tests. Over a measured course the Avro clocked a speed of 80-9 m.p.h. and climbed to 1,000 feet in 1 min 45 sec; the stalling speed was 43 m.p.h. The tests were carried out with a passenger and three hours’ fuel on board.
  These performance figures made a deep impression at the time, but their impact was somewhat lessened when, only five days later, the Sopwith Tabloid put up an even better performance in the same tests.
  Raynham made several outstanding flights on the Avro 504. On February 4th, 1914, he flew the machine to a height of 15,000 feet, thereby comfortably exceeding the existing British altitude record of 13,140 feet which had been set up by Captain J. M. Salmond on a B.E.2. Raynham had taken off from Brooklands, and from his machine’s ceiling he glided to Hendon, about twenty miles away, with his engine off. After gliding down for twenty-five minutes he was over Hendon at 5,000 feet, so he spiralled down and landed there without again using his engine.
  This flight was a magnificent exhibition of airmanship, but the climb could not count as a record because it was not officially observed. Six days later Raynham made a formal attempt on the altitude record and, with MacGeagh Hurst as passenger, took the Avro to 14,420 feet.
  Soon after these flights, the Avro 504 was bought by the Daily Mail and toured the country giving exhibition flights. The Avro’s new owners required it to be flown from the sea at coast resorts; the manufacturers therefore made and provided a float undercarriage which was interchangeable with the normal wheels. A floatplane version was exhibited at the Olympia Aero Show in March, 1914. This particular Avro 504 was probably one of the first production machines, for the upper longerons of its fuselage sloped downwards behind the cockpits.
  When the prototype was given its float undercarriage a change of power-plant was made at the same time. It was thought that the original 80 h.p. Gnome, with its actual output of little more than 62 h.p., might not provide sufficient power for the heavier seaplane version; and it was replaced by an 80 h.p. Gnome Monosoupape seven-cylinder rotary engine, which was supposed to be more powerful than the ordinary Gnome of the same nominal power. The choice was an unfortunate one, for the new engine proved to be far from satisfactory and gave a great deal of trouble. It finally brought about the destruction of the Avro 504.
  During the Daily Mail tour the Avro was flown by F. P. Raynham and George Lusted, and its first flight as a seaplane was made at Paignton in April, 1914. In August it was at Shoreham, on floats. It was commandeered as soon as war was declared on the 4th of that month but was destroyed two days later: the engine failed as Raynham took off to deliver the machine to the Services, and he had insufficient height to avoid crashing on land.
  In the early summer of 1914 the War Office ordered twelve Avro 504s and the Admiralty ordered one. In the construction of these machines there arose a remarkable example of lack of cooperation between the War Office and the Admiralty. Before acceptance of the type for Service purposes the design of the airframe had been studied by both Departments. The War Office accepted the structure in its designed form, but the Admiralty requested that spars of slightly greater cross-section be fitted. Avros, looking ahead to further orders, naturally wished to avoid the production complications which the use of different spars would mean, and asked the War Office to adopt the size of spar specified by the Admiralty. This the War Office declined to do. Consequently all the Admiralty Avro 504 variants had slightly larger spars than the machines which were built for the R.F.C., an anomaly which persisted until the amalgamation of the R.F.C. and R.N.A.S. in 1918, by which time spars of the original dimensions had been standardised in the 504K. All the production 504s had one feature in common: the rear fuselage was modified to be symmetrical in side elevation, so that the upper longerons sloped downwards behind the rear cockpit.
  In the R.N.A.S. the Avro was frequently referred to as the Avro 179, a designation obtained by using the serial number of the first machine accepted by the Admiralty. Inevitably, the use of this designation has led to some confusion.
  Some of the R.F.C. Avros were delivered before the outbreak of war, and the remainder were handed over soon afterwards. When No. 5 Squadron went to France on August 13th, 1914, its equipment included a few Avro 504s; but the type was never used in large numbers by front-line units. In fact, the greatest known number of Avros on the strength of the R.F.C. squadrons in France is only thirteen. On March 10th, 1915, No. 1 Squadron had eight, No. 3 had one, and No. 5 had four. Six months later the R.F.C. had seven in France, four with No. 1 Squadron and three with No. 5.
  Service use in the field showed that the Avro 504’s flight endurance was too short, and later production aircraft had increased tankage which brought the endurance up to 4 1/2 hours.
  One of the Avros of No. 5 Squadron was the first British aeroplane to be brought down by the enemy. On August 22nd, 1914, the machine flown by Lieutenant V. Waterfall (observer, Lieutenant C. G. G. Bayly) was shot down by infantry fire in Belgium, and it has been surmised that this Avro may have provided the Germans with the first positive evidence that British forces were in the field against them.
  Commander Samson’s Eastchurch Squadron of the R.N.A.S. received its first Avro 504 on November 27th, 1914. This machine set out to bomb the submarine depot at Bruges on December 14th with four 16-lb bombs but Flight Sub-Lieutenant R. H. Collet, its pilot, could not find Bruges in bad visibility, and bombed the Ostend-Bruges railway line instead.
  In common with its contemporaries, the Avro 504 had not been designed to carry any kind of offensive armament, and it was flown from the rear seat. The observer sat directly under the centre-section and had a centre-section strut at each corner of his cockpit. The chances of operating a machine-gun satisfactorily from that position were remote indeed. Nevertheless, various attempts were made in the field to provide some kind of useful armament.
  One of the earliest of these attempts was made on Avro 504 No. 383 in mid-October, 1914. The Avro had been delivered to No. 5 Squadron on October 15th, and within a few days it had been fitted with a Lewis gun by its pilot, Second Lieutenant L. A. Strange, who was assisted by Captain L. da C. Penn-Gaskell. The “gun-mounting” would probably have delighted Mr Heath Robinson, and is best described in Wing-Commander Strange’s own words (in his book Recollections of an Airman):
  “The mounting consisted of a metal tube, which I carefully selected from the tail boom of a wrecked Henri Farman. The gun lay on the top of the fuselage decking, while a piece of rope, lashed around its centre of balance, was passed up over the metal tube and fixed to the cross member of the front seat tank bearer, for it must be remembered that in those days the front seat was on top of the petrol tank. A pulley on the rope enabled the observer to sling the gun up into mid-air and fire it all round as well as back over the pilot’s head, with the aid of a stock from the shoulder.”
  On October 22nd, 1914, Strange and Penn-Gaskell carried out what was probably the first ground-strafing attack of the war when they brought the Avro’s Lewis gun into action against a train and enemy troops at Perenchies siding. Exactly one month later, Lieutenant Strange, with Lieutenant F. G. Small as his observer, forced down an Albatros two-seater near Neuve-Eglise.
  Military actions in which the Avro 504 took part were few, but the most audacious and brilliant by far was the R.N.A.S. raid on the Zeppelin sheds at Friedrichshafen, Lake Constance.
  While Strange and Penn-Gaskell were strafing Perenchies in No. 383, Lieutenant Noel Pemberton Billing of the R.N.V.R. was on his way to Belfort to prepare for the attack; he arrived there on October 24th, 1914. When his preparations were complete he returned to England on October 28th to collect the aeroplanes and pilots for the execution of the raid.
  A special flight of four Avro 504s had been formed at Manchester under Squadron Commander P. Shepherd, and the pilots were Squadron Commander E. F. Briggs, Flight Commander J. T. Babington, Flight-Lieutenant S. V. Sippe and Flight Sub-Lieutenant R. P. Cannon. The Avros, officers and eleven air mechanics arrived at Belfort by night on November 13th, ic) rq.. Soon after their arrival Squadron Commander Shepherd was taken ill; the weather was bad, and a strong easterly wind delayed the attack for a week.
  On Saturday, November 21st, the weather improved sufficiently for the raid to take place, and the Avros were brought out for engine and bomb-rack tests. The aeroplanes were brand-new: they were, in fact, the first four Avros to be delivered to the Admiralty, and were numbered 179, 873, 874 and 875. Their 80 h.p. Gnome engines were not new, however, which was probably one reason why no test flights had been made with the aircraft; the raid itself was their first flight. There was at that time no such thing as a standard bomb-rack, and the Avro company designed and made the racks for the four machines. A. V. (later Sir Alliott Verdon) Roe said they were “a Heath Robinson job”, but they served well enough in the event. Stowage was provided for four 20-lb high explosive bombs and four incendiaries, but for the raid each aircraft carried only four 20-lb bombs.
  The Avros left Belfort at five-minute intervals. Squadron Commander Briggs was first to go on No. 873, followed by Babington on 875 and Sippe on 874. Cannon’s machine broke its tailskid and was unable to take off. Over the target Sippe’s fourth bomb refused to leave the rack, but two of the eleven which dropped in the target area did all that was necessary. These fell on the airship sheds. One damaged a Zeppelin which was inside; the other destroyed the gas-works, which exploded and did great damage. The raiders did not escape unscathed, for Briggs was shot down and nearly lynched after crashing. No. 875 was later on the strength of No. 1 Squadron, R.N.A.S., but did not return from a raid on enemy positions on February 16th, 1915: its pilot on that occasion was Flight-Lieutenant E. G. Rigall.
  The Avro 504 was less successful against the Zeppelin in its own element. The L.Z.38 was intercepted by Flight Sub-Lieutenant Mulock of Westgate R.N.A.S. Station about 3.30 a.m. on May 17th, 1915, but the airship climbed away too rapidly to allow Mulock to attack with his Avro’s load of two grenades and two incendiary bombs.
  That same night, soon after Mulock’s adventure, Flight Commander A. W. Bigsworth, in another Avro, was pursuing the L.Z.39 towards Ostend. At 10,000 feet over the town he was 200 feet above the airship, and he dropped his four 20-lb bombs on it. Smoke issued from the Zeppelin’s stern, but it was not destroyed. Ultimately, and in a damaged condition, it made a rough landing at Evere.
  With the standardisation of the B.E.2C the Avro ceased to be a front-line aircraft with the R.F.C., but continued in limited service with the R.N.A.S. In point of fact, the Avro company were at one time told that they would have to stop making 504s, which were regarded as obsolete, and undertake the manufacture of B.E.2c’s; production of the Avro might continue until instructions for the building of the B.E.2 were issued. Fortunately, those instructions were never forthcoming.
  The basic design was modified in detail as time went on, and each successive variant was identified by the addition of a suffix letter to the Avro’s type number. The 504A retained the 80 h.p. Gnome engine, but had ailerons of reduced span and interplane struts of broader chord. On some 504As the lower wingroots were uncovered for about 12 inches on either side in order to improve the downward view. The tailskid remained attached to the bottom of the rudder. The first true 504As were the fifty machines numbered 2890-2939, but the designation is sometimes loosely applied to the sixty-three production 504s which had preceded them. The 504A was built in considerable numbers.
  As part of the natural sequence of events, the Avro was relegated to training duties after its withdrawal from active service. Dual control had to be installed, and Avros designed a neat dual control umt comprising seats, bearers, control columns, rudder bars and heel rests This unit could be assembled separately and inserted complete into the fuselage. Trainer versions of the Avro 504 design were issued to training units from 1915 onwards.
  The next sub-type, the Avro 504B, was an R.N.A.S. version. It set a new fashion followed in all subsequent R.N.A.S. Avro 504 variants, by having a plain rudder attached to a large low aspect-ratio fin. The 504B reverted to the long ailerons, which also remained standard on R.N.A.S. Avros, and there were quadrantal cut-outs at the trailing edge of the lower wing-roots. On the first 504Bs the sides of the rear cockpit were cut a little below the level of the upper longerons; but on later machines the upper longerons were unbroken, and the rear cockpit was surmounted by a circular frame on which a Scarff ring-mounting could be installed when required.
  The Avro 504B was the first variant to have a pylon-type tailskid similar to that of the B.E.2c, a fitting which remained standard on all subsequent 504 sub-types. Some 504Bs were used operationally from Dunkirk, but the type was more widely used by the R.N.A.S. as a trainer. Thanks to its large fin it was much more difficult to spin than the R.F.C. versions. The standard power-plant was the 80 h.p. Gnome, but when supplies of that engine ran short some 504Bs were fitted with the 80 h.p. Le Rhone.
  An Avro 504B was among the aircraft which were used in the earliest experiments with arrester gears intended for use on aircraft-carrying ships.
  The endurance of the Avro, even when increased to 4 1/2 hours, was still considered to be insufficient for long-distance reconnaissance flights or anti-Zeppelin patrols. A single-seat version with greater fuel capacity was therefore ordered. This was designated 504C, and had a large cylindrical tank installed in the position normally occupied by the front cockpit; the endurance was no less than eight hours. The 504C was an R.N.A.S. variant, and the airframe was virtually identical to that of the 504B. The cockpit corresponded to the rear cockpit of the 504B, and its sides were similarly cut below the level of the upper longerons. The 504C had the R.N.A.S. wings with long ailerons, and the large fin and plain rudder were fitted. The engine was still the 80 h.p. Gnome.
For anti-Zeppelin duties some Avro 504Cs had an aperture in the centre-section through which a Lewis gun fired upwards at an angle of about 45 degrees. A similar single-seat conversion for the R.F.C. was designated 504D, and probably bore the same relationship to the 504A as the 504C did to the 504B. It is doubtful whether the 504D was built in quantity, whereas an appreciable number of 504Cs (at least 80) were built. Again the engine was the 80 h.p. Gnome.
  It was felt that the Avro was somewhat underpowered with the 80 h.p. Gnome, and A. V. Roe & Co. were asked to fit other types of engine to improve the performance. The 100 h.p. Gnome Monosoupape was fitted to a new 504 variant for the R.N.A.S. which differed considerably from all other war-time sub-types of the Avro 504: this version was designated 504E. It had a new fuel system with pressure feed from the main tank, which was installed behind the front seat; the rear cockpit was moved one bay farther aft. The change in the position of the C.G. was taken care of by reducing the stagger from the standard value of 24 inches to about 9 inches. The front centre-section struts were attached to the upper longerons at the normal points, but the attachment points for the rear struts were moved one bay farther aft. Thus the centre-section struts converged upwards in side elevation.
  Externally, the engine installation of the Avro 504E looked no different from that used on its predecessors, but in fact the steel tube “spider” which carried the nose bearing was altered to accommodate the larger engine. In construction the fuselage of the 504E recalled that of the prototype Avro 504, for the upper longerons were quite straight when seen in side elevation. The R.N.A.S.-pattern wings, ailerons and tail unit were fitted. Only ten Avro 504Es were built; some were used for training purposes at Chingford and Fairlop, and one went to Cranwell.
  At the suggestion of the Admiralty, an installation of the six-cylinder Rolls-Royce in-line engine was made in 1916. This engine had a nominal output of 75 h.p., and was widely used to power the various types of non-rigid airships of the S.S. Class. The Avro in which the Hawk was installed was No. 8603, the last machine of a batch of thirty Avro-built 504Cs; and the designation 504F was given to the modified aircraft. Although it was said to be very pleasant to fly, the 504F was still underpowered and no production was undertaken; but there are indications that a second machine may have been fitted with a Hawk engine. A contract for thirty machines placed by the Admiralty with a firm of contractors was cancelled and replaced by one for the standard 80 h.p. Gnome Avro.
  In Mr R. J. Parrott’s lecture entitled “The History and Evolution of the Avro training machine”, given before the Institution of Aeronautical Engineers on January 9th, 1925, the Avro 504G was described as “... an Army machine ... fitted with the then new 130 h.p. Clerget engine. It was fitted with a synchronised Vickers Gun and also a Lewis Gun in the rear cockpit. It was intended for instruction in air fighting. Only ten were constructed, and they did not achieve any great measure of success.”
  That description could apply to the Avro shown in Plate 46, but for the fact that the aircraft illustrated had the large fin and plain rudder which identify it as an R.N.A.S. sub-type.
  The Avro 504 variant which was known in the R.N.A.S. as the 504G was a conversion of the 504B and was used as a gunnery trainer. A Scarff ring-mounting was fitted to the rear cockpit, and a fixed synchronised Vickers gun was fitted for the pilot’s use. The engine was the 80 h.p. Gnome.
  Mention has already been made of the modest part played in the early arrester-gear experiments by a modified Avro 504B. Another variant of the Avro 504 was successfully used in the course of experiments of quite the opposite nature, but also intended to aid the development of flying from ships. As is related in the history of the Fairey F.127, the Admiralty invited tenders for the construction of aircraft catapults in 1916, and two types of catapult were subsequently ordered. One was built by Waygood-Otis to the design of Mr R. F. Carey. The first aeroplane to be launched from this catapult was a specially modified Avro 504C which was suitably strengthened, provided with catapult pick-up points, and fitted with a special padded seat with neck support for the pilot. The modified machine was re-designated 504H. The modifications were made under the supervision of Squadron Commander E. H. Dunning, that great pioneer of deck-flying. Unhappily, before the tests of the catapult could be conducted, Dunning was killed on August 7th, 1917, in his third attempt to land a Sopwith Pup on the forward deck of H.M.S. Furious. Flight Commander R. E. Penny volunteered to be catapulted in the Avro 504H. The launch was made successfully and Penny landed safely.
  In the autumn of 1916 a new 504 variant was built for the R.F.C. This was the 504J, powered by the 100 h.p. Gnome Monosoupape engine, and more popularly known to the R.F.C. as the Mono-Avro. The engine was installed in the usual nose-bearing mounting, and the cowling was little different from that of the other rotary-powered Avros. The R.F.C.-pattern wings with short ailerons were fitted, and there was no tail fin. As the supply of Mono-Gnomes permitted, machines which had been ordered as 504As were built as 504Js; production aircraft began to appear in 1917 and were issued to R.F.C. training aerodromes.
  At the end of 1916, Major R. R. Smith-Barry was given command of No. 1 Reserve Squadron at Gosport. He had qualified for his R.Ae.C. aviator’s certificate (No. 161) on November 28th, 1911, and had gone to France with No. 5 Squadron in August, 1914. After recovering from injuries sustained in the crash of his B.E.8, he had served at home as an instructor, and had flown at night on anti-Zeppelin patrol. In July, 1916, he was given command of No. 60 Squadron, and returned to England in the following December.
  In his duties with No. 1 Reserve Squadron, Smith-Barry evolved an instructional technique which consisted largely of demonstration and explanation. At that time so little was known about the reasons for an aeroplane’s reactions to control movements that the Smith-Barry system was revolutionary in its approach, but soon proved its worth in the results it produced. No. 1 Reserve Squadron acquired an enviable reputation and was known throughout the R.F.C. as a thoroughly efficient training unit.
  Major-General J. M. Salmond, who was then in command of Training Division, had given Major Smith-Barry a completely free hand. When the results proved to be so excellent, Major-General Salmond recommended that No. 1 Reserve Squadron be expanded and developed as a School of Special Flying, with the main object of training flying instructors in order that the Smith-Barry system might be spread throughout the R.F.C.’s training organisation. This was done in August, 1917, by the addition of Nos. 27 and 55 Training Squadrons.
  The chosen instrument of the Gosport School was the Avro 504J, and Smith-Barry gave a salutary shock to the contemporary philosophy of flying training by giving ab initio instruction on it. Up to that time opinions of the Avro were remarkably diverse; they varied from the one extreme of regarding the machine as a dangerous, over-sensitive aeroplane, to the other of recognising it as the delightful aircraft it was. At all training stations, however, it had been regarded as an advanced type to which pupils graduated after receiving elementary instruction on such types as Maurice Farman Longhorns and Shorthorns.
  In its time and in relation to contemporary front-line types, the Avro 504J was very nearly ideal as a trainer. The controls were light and powerful, and the machine’s response to their use was both lively and positive. The sensitivity of the controls was a great aid to the Smith-Barry doctrine of demonstration, and at the same time revealed pupils’ faults immediately. The rotary engine gave pupils a realistic foretaste of what they might expect on rotary-powered Service types; and the narrow track of the undercarriage permitted the demonstration of torque effect on take-off, for it revealed the Avro’s tendency to swing. In this further respect, therefore, pupils learned what was to be expected of scouts with higher-powered rotary engines. The fact that the 100 h.p. Mono-Gnome would continue to turn over freely when switched off enabled forced landings to be taught realistically, and the engine was controlled by a single lever only.
  The rate of climb was good enough to enable a useful height to be reached in a reasonable time, and the Avro could perform all aerobatics known at that time. The Avro 504J deserves to be remembered as the aeroplane which made possible the R.A.F.’s system of flying training, a system which, at its inception, was far ahead of any other method of instruction and which, but little modified, remains in use today.
  The exploits of the Gosport Avros in the hands of such pilots as Captain Williams, Captain Foote, Captain Duncan-Davis and Major Brearley have assumed a near-legendary quality which was not surpassed by any of the warlike achievements of the Avro’s operational contemporaries. The “party piece” of Captain Williams, commander of “C” Flight, was to land between two hangars more or less regardless of wind direction, turning completely round immediately after touching down and finishing his landing run inside “C” Flight’s hangar. Williams’ machine was the 504J C.4448.
  Another distinguished Avro 504J was C.4451. It was on that machine that H.R.H. Prince Albert, later King George VI, learned to fly.
  Such was the fame of the Gosport system that in 1918 four Gosport instructors and four Mono-Avros were sent to France to advise and assist in the training of French pilots.
  At Gosport, pilots were not only permitted but were expected to fly their Avros to the limits of the machines’ capabilities. Not only did this instil great confidence and flying skill, but it also provided the most thorough test of the aircraft; and Gosport became an authority on Avros and what could or could not be done on them.
  Some experiments were carried out there. Single-bay wings of reduced span were fitted to B.4264, and the modified machine performed very well. Standard wings were later fitted, but with the gap reduced to 5 ft 1 1/4 in.
  One important consequence of the success of the Gosport system was the decision to standardise the Avro 504J as the R.F.C.’s training aeroplane. The demand for the Avro swelled enormously, and contracts were placed with a large number of manufacturers.
  Unfortunately, contracts for the 100 h.p. Monosoupape engine had been allowed to run down as it ceased to be used in front-line aircraft. British production of the engine was tapering off towards the end of 1917, and despite its revival in 1918 it was obvious that Mono-Gnomes would not be forthcoming in sufficient quantities to equal the output of Avros.
  To overcome this difficulty, all surplus rotary engines were recalled from all aerodromes in England and France. This action produced a mixed collection of 130 h.p. Clergets, 110 h.p. Le Rhones and even 80 h.p. Le Rhones. The installation of the 80 h.p. Le Rhone was a fairly straightforward job, and some 504JS had that engine. The larger engines did not fit into the airframe so easily, and modification was necessary. Lieutenant Colonel Smith-Barry has been credited with the idea of making the 130 h.p. Clerget, 110 h.p. Le Rhone and 100 h.p. Gnome Monosoupape interchangeable in the Avro; and it is relevant to recall that one of the experiments carried out at Gosport in 1917 was the installation of a 130 h.p. Clerget in the 504J, B.3157.
  A. V. Roe & Co. did in fact devise adaptors by means of which any of the engines would be fitted into the Avro 504 airframe. All were carried on an overhung mounting and had an open-fronted cowling. The modified machine was designated Avro 504K, regardless of the type of engine. Production machines appeared with all of these engines, and were distributed to every training unit at home and to others in Egypt, India, Australia and Canada.
  It was recognised that the Egyptian climate might affect the wooden airframe adversely, and in 1918 some 504-type wings of steel construction were sent there to observe the effects of the climate on steel structures.
  Many 504Js were converted to become 504Ks, and machines which had been ordered under contracts for 504As and 504Js were modified during construction to become 504Ks. Production was undertaken on an enormous scale, and the total number of all Avro 504 variants which were built during the war exceeded the production of any other individual type of British aeroplane of the period. In 1918 production of the 504K was initiated in Canada at the factory of Canadian Aeroplanes Ltd., the Government-sponsored undertaking which had taken over the Curtiss works and staff at Long Branch, Toronto, late in 1916. It seems clear that the intention was for the Avro to replace the Curtiss JN-4 at training stations in Canada, and gives an interesting indication of the official opinion on the relative merits of the two machines. The initial contract was for 100 Avro 504Ks, but only one, or at most two, had been delivered by the time ot the Armistice.
  The British Liaison Officer in Washington, Colonel Lee, was of the opinion that the Avro was the finest trainer ever built, and he had one sent to America during the winter of 1917-18. It made several demonstration flights over Washington. The Americans wanted large numbers of 504Ks but could obtain only a few which they used at Issoudun for instruction in aerobatics.
  One of the little-known facts in the Avro’s history is that the 504K was issued to Home Defence squadrons as a fighting aircraft from the beginning of 1918. By the end of 1917 it had become evident that the F.E.2b’s which were in use with some Home Defence units were ineffective because of their low ceiling. It was therefore decided to re-equip the northern group of squadrons with single-seat conversions of the Le Rhone Avro 504K: in this form the type could reach a ceiling of 18,000 feet. It was also thought that experience gained by pilots in handling the Avro and its rotary engine would make them suitable for later transfer to the Camel-equipped Home Defence squadrons in the south. Avro 504Ks still equipped five squadrons at the Armistice, by which time they were due to be replaced by Sopwith Camels.
  The Home Defence Avros were armed with a single Lewis gun on a Foster mounting above the centresection; a similar installation had been made on the 504J, C.4364. The front cockpit of the fighter 504Ks was faired over, and the gravity tank was moved out on to the port upper wing to make way for the gun-mounting. In an endeavour to improve their performance, some of the 504K fighters were fitted with a vee undercarriage similar to that of the Avro 521. The vees were attached to the fuselage at the normal pick-up points for the struts which supported the central skid of the standard undercarriage, and were consequently unusually broad.
  The Sunbeam Motor Car Co., Ltd., were contractors for the Avro 504B, J and K, and in 1918 they fitted a 504K airframe with one of their own Dyak engines of 100 h.p. There is no record of further British development of the Dyak-powered 504K, but seven Avros with Dyak engines were built in Australia in 1920 by the Australian Aircraft and Engineering Co., Ltd., at Mascot, Sydney, N.S.W. The first Australian Dyak-Avro was delivered to the then newly-formed Queensland and Northern Territories Aerial Services Co., Ltd. This Avro proved to be exceptionally reliable in the very trying conditions under which it had to operate.
  The last war-time variant of the Avro 504 was a seaplane conversion of the 504K which was designated 504L. Two single-step pontoon floats replaced the wheel undercarriage of the Avro C.4329, and a tail-float was attached directly to the bottom longerons. A fin was added to the tail-unit, but was shaped to accommodate the balance area of the original comma-shaped rudder. Each float originally had only two struts to connect it to the fuselage, but an additional strut was later provided to each rear float attachment point.
  After the Armistice the Avro 504J and 504K continued in service as the R.A.F.’s standard training aircraft. The 504J was declared obsolete in September, 1921, but the 504K carried on for many years. It also helped to lay the foundations of several of the air forces of the Commonwealth countries, to which numbers of British aeroplanes were presented in 1919 as an Imperial Gift.
  The development of the Avro 504 design did not cease with the Armistice. A long line of descendants appeared in the post-war years and added further lustre to the fine reputation of a great aeroplane. Many foreign countries adopted the type, and 504Ks were built in Japan and in post-revolutionary Russia; in the latter country the Avro was known as the U-1 and its engine (a copy of the 110 h.p. Le Rhone) was designated M-2.
  In many forms, in many lands, with many different engines, the ageless Avro gave faithful service, both military and commercial. Its longevity was perhaps its best testimonial and memorial.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester; and at Hamble.
  Contractors: The Bleriot & Spad Aircraft Works, Addlestone, Surrey. The Brush Electrical Engineering Co., Ltd., Loughborough. The Eastbourne Aviation Co., Ltd., Eastbourne. The Grahame-White Aviation Co., Ltd., Hendon, London, N.W.9. Harland & Wolff, Ltd., Belfast. The Henderson Scottish Aviation Factory. Hewlett & Blondeau, Ltd., Oak Road, Leagrave, Luton. The Humber Motor Co., Ltd., Coventry. Morgan & Co., Leighton Buzzard. Parnall & Sons, Mivart Street, Eastville, Bristol. The Regent Carriage Co., Ltd., Fulham. Frederick Sage & Co., Ltd., Peterborough and London. S. E. Saunders, Ltd., East Cowes, Isle of Wight. Savages Ltd., King’s Lynn, Norfolk. The Sunbeam Motor Car Co., Ltd., Wolverhampton. Canadian Aeroplanes Ltd., Toronto, Ontario, Canada.
  Power: 504 prototype: 80 h.p. Gnome, later 80 h.p. Gnome Monosoupape. Production 504 and 504A: 80 h.p. Gnome. 504B: 80 h.p. Gnome or 80 h.p. Le Rhone. 504C and 504D: 80 h.p. Gnome. 504E: 100 h.p. Gnome Monosoupape. 504F: 75 h.p. Rolls-Royce Hawk. 504G and 504H: 80 h.p. Gnome. 504J: 100 h.p. Gnome Monosoupape or 80 h.p. Le Rhone. 504K: 100 h.p. Gnome Monosoupape or 110 h.p. Le Rhone or 130 h.p. Clerget; experimental installation of 100 h.p. Sunbeam Dyak. 504L: 130 h.p. Clerget or 150 h.p. Bentley B.R. 1.
  Dimensions: Span: 36 ft. Length: 29 ft 5 in. (28 ft 11 in. with Sunbeam Dyak). Height: 10 ft 5 in. Chord: 4 ft 9 3/4 in. Gap: 5 ft 6 in. Stagger: 2 ft (except 504E). Dihedral: 2 30'. Incidence: 4. Span of tail: 10 ft. Airscrew diameter: 9 ft. Tyres: 700 X 100 mm.
  Areas: Wings: upper 173 sq ft, lower 157 sq ft, total 330 sq ft. Ailerons: each 11-35 sq ft, total 45-4 sq ft. Tailplane: 26 sq ft. Elevators: 18 sq ft. Rudder: 9 sq ft.
Weights (in lb): Military Fuel and
Empty Load Crew Oil Loaded
504 prototype - - 360 - 1,550
504 floatplane 1,070 - 360 - 1,719
504 production 924 - 360 - 1,574
504K (Mono-Gnome) 1,100 90 360 250 1,800
504K (Le Rhone) 1,231 Nil 360 238 1,829
504K (Dyak) 1,320 Nil 360 177 1,857
Performance: Maximum speed (m.p.h) at
ground level 6,500 ft 8,000 ft 1,000 ft
504 prototype 81 - - -
504 floatplane 75 - - -
504 production 82 - - -
504A - 62 - -
504K (Mono-Gnome) - 82 - 75
504K (Le Rhone) 95 - 87 85
504L (Clerget) 90 - - -

  Climb to
   3,500 ft - 504: 7 min (with 80 h.p. Gnome Monosoupape). 504A: 9 min 30 sec. 504.K. (Le Rhone): 5 min.
   6,500 ft - 504A: 25 min.
   8,000 ft - 504K (Le Rhone): 10 min.
   10,000 ft - 504K (Le Rhone): 16 min.

  Service ceiling: 504K (Monosoupape) 13,000 ft; 504K (Le Rhone) 16,000 ft

  Armament: In the early days of the war the observer carried a rifle, and a few home-made gun mountings of various kinds were used in the field to enable the observer to use a Lewis machine-gun. The early service 504 carried four 20-lb bombs, as also did some of the Home Defence Avros. For anti-Zeppelin work incendiary bombs and grenades were carried. Some Avro 504Cs had a Lewis gun firing upwards at an angle of about 450 through an aperture in the centre-section. Home Defence single-seaters had a Lewis gun on a Foster mounting above the centre-section. The 504G had a fixed synchronised Vickers machinegun for the pilot, and a Lewis gun on a Scarff ring-mounting was fitted to the rear cockpit.
  Service Use: France: Avro 504 used by R.F.C. Squadrons Nos. 1, 3 and 5. R.N.A.S. Squadron No. 3 (one Avro received November 27th, 1914; on February 6th, 1915, two were on this unit’s strength). R.N.A.S. Squadron No. 1 (eight Avros delivered mid-December, 1914; five on strength on February 26th, 1915). Dardanelles: No. 2 Wing R.N.A.S., Isle of Imbros. Home Defence: R.F.C. Squadrons Nos. 33, 51, 75, 76, 77 and 90. R.N.A.S. Stations, Westgate, Great Yarmouth. Training Duties: before the end of 1918 the Avro 504 had been issued in one form or another to every training unit in Great Britain. Trainer versions were used at the Royal Aircraft Park, Farnborough, at Shawbury, at Central Flying School, Upavon, and at the Schools of Aeronautics at Bath, Bristol, Cheltenham, Denham, Oxford and Reading; at Flying Instructors’ Schools at Gosport (S.W. Area), Shoreham (S.E. Area), Lilbourne (Midland Area), Redcar (N.E. Area), Ayr (N.W. Area) and Curragh (Ireland). Used by squadrons working up before going overseas; e.g. Nos. 24, 45, 65. No. 45 Squadron had six Avros on March 30th, 1916. Used for night-flying training by Squadrons Nos. 186, 188 and 190, R.A.F., at East Retford, Throwley and Newmarket respectively. Used by the R.N.A.S. at Cranwell, Chingford, Frieston, Redcar, Port Victoria, War School at Manston. Egypt: 20th Training Wing, Abu Qir. Australia: Australian Flying Corps School, Point Cook. Canada: Gamp Borden, Ontario. New Zealand: 504KS used at flying schools after the war. South Africa: used by the S.A.A.F. after the war. American use: in July, 1918, fifty-two Le Rhone-powered 504K.S were purchased by America for the use of the A.E.F. as trainers. Some were used at the A.E.F. 3rd Instruction Centre, Issoudun. France: four Gosport instructors and four Mono-Avros were sent to France in 1918 to advise and assist in the training of French pilots.
  Production and Allocation: During the war period, 8,340 Avro 504s were produced. Of these, 3,696 were built by A. V. Roe & Co., Ltd., and 4,644 by other contractors. Deliveries to the R.F.C. and R.A.F. totalled 5,446, of which 4,771 went to Training Units, 274 to Home Defence Units, nine to the Expeditionary Force (in 1914), and 392 to the Middle East Brigade. On October 31st, 1918, there were 2,999 Avros on charge with the R.A.F. Ten were at Aeroplane Repair Depots; sixteen in store; ten at Aircraft Acceptance Parks; 2,267 were at Flying Schools and various Home Establishment aerodromes; 226 were with Home Defence squadrons; 184 were with the 1 ith (Irish) Group; 111 were in Egypt and Palestine; and 175 were destined for Middle East stations.

  Costs:
   Avro 504K airframe less engine and instruments £868 19s.
   100 h.p. Gnome Monosoupape engine £896 0s.
   110 h.p. Le Rhone engine £771 10s.
   130 h.p. Clerget engine £907 10s.

Avro 510

  THE Avro 510 was a large and rather ungainly twin-float seaplane which was originally designed for the Daily Mail “Circuit of Britain” seaplane race of 1914. Owing to the outbreak of war the contest never took place, and it is quite probable that the original machine would be impressed for service with the R.N.A.S. At least five Avro 510s were built for the R.N.A.S. and were used for coastal patrol duties.
  The prototype had a large balanced rudder, similar to but larger than that of the Avro 504, and each float was connected to the fuselage by two struts only: the floats of the prototype were built with a single step. The Service machines had a fixed fin added to the tail-unit: it had a curved trailing edge to match the leading edge of the rudder. The undercarriage of the later Avro 510s was noticeably taller than that of the prototype, and the rear attachment point of each float was joined to the fuselage by a vee strut. These floats were of the simple pontoon type, similar in appearance to those of the Short 184.
  All the Avro 510s had the 150 h.p. Sunbeam engine, but exhausts varied. Twin stacks were used, each stack consisting of the four exhaust pipes from each bank of cylinders; but at least one machine had one single central exhaust stack.
  There are references to a version of the Avro 510 powered by a 160 h.p. Gnome rotary engine, but it is uncertain whether it was ever built in that form. At least one Avro 510, No. 130, survived until September, 1917: it was at Calshot seaplane station until that date.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester; and at Hamble.
  Power: 150 h.p. Sunbeam.
  Dimensions: Span: upper 63 ft, lower 38 ft. Length: 38 ft. Chord: 6 ft. Gap: 6 ft 6 in.
  Areas: Wings: 564 sq ft.
  Weights: Empty: 2,080 lb. Loaded: 2,800 lb. (Corresponding figures quoted for version with 160 h.p. Gnome were 2,005 lb and 3,215 lb respectively.)
  Performance: Maximum speed: 70 m.p.h. Climb to 1,000 ft: 4 1/2 min; to 3,000 ft: 15 min. Endurance: 4 1/2 hours. Service Use: R.N.A.S. Seaplane Station, Calshot.
  Serial Numbers: 130-134, built under Contract No. C.P.30654/14.

Avro 523, the Pike

  THE Pike was the first twin-engined aeroplane to be built by the Avro company. The first machine was tested in May, 1916, and was powered by two Sunbeam engines, each of 160 h.p., which were installed as pushers. The airscrews were driven by extension shafts, and rotated in opposite directions. Wings and tailplane were simple rectangular surfaces with square extremities, and a balanced rudder of generous area was fitted to the large, low aspect-ratio single fin.
  The aircraft had good lines and was of advanced conception for its day. Indeed, the basic proportions changed but little between the Pike and the Manchester of 1918, and the family likeness between the two types was pronounced.
  The Pike was designed as a bomber, and had a good performance on only 320 h.p. It is not easy to find a reason why the type was not produced in quantity, but it is possible that the Short Bomber had been adopted as the standard R.N.A.S. bombing aircraft by the time the Pike appeared. The fact that the Short machine utilised a number of standard Short 184 components facilitated its production. Moreover, the Handley Page O/100 was in prospect, with the promise of weight-carrying capabilities much greater than those of the Pike.
  The first Pike was sent to the R.N.A.S. Station at the Isle of Grain, where it was tested by F. P. Raynham. During an early flight, with R. H. Dobson (later Sir Roy Dobson) in the rear cockpit, the machine proved to be seriously tail-heavy, possibly due to an experimental distribution of loads. The Pike became sufficiently controllable to be landed only because Mr Dobson climbed along the fuselage to the bow cockpit, a performance which was fraught with danger. The transference forward of Dobson s weight enabled Raynham to throttle down the engines without stalling the aircraft, and a successful landing was made.
  A second Avro 523 was tested in August, 1916, but differed in having two 150 h.p. Green engines which were installed as tractors. The Pikes were built at A. V. Roe’s Manchester works but were sent to the Hamble experimental works for completion.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester; final assembly at Hamble works.
  Power: Two 160 h.p. Sunbeam (pushers); two 150 h.p. Green (tractors).
  Dimensions: Span: 60 ft. Length: 39 ft 1 in. Chord: 7 ft. Gap: 7 ft 3 in. Stagger: nil. Dihedral: 3 30'. Incidence: 4.
  Areas: Wings: upper 418 sq ft, lower 397 sq ft, total 815 sq ft. Ailerons: each 30-5 sq ft, total 122 sq ft. Tailplane: 80 sq ft. Elevators: 45 sq ft. Fin: 17-5 sq ft. Rudder: 21 sq ft.
  Weights: Empty: 4,000 lb. Loaded: 6,064 lb.
  Performance: Maximum speed at ground level: 97 m.p.h.; at 10,000 ft: 88 m.p.h. Climb to 5,000 ft: 9 min 30 sec;
to 10,000 ft: 27 min. Endurance: 7 hours.
  Armament: One Lewis machine-gun on rotatable ring-mounting on nose cockpit; a second Lewis gun on a similar mounting on rear cockpit aft of wings. Bombs could be carried.



Avro 529 and 529A

  THE Avro 529 and 529A were ordered by the Admiralty in 1916, and were intended for service with the R.N.A.S. as long-range bombers. The type was developed from the earlier Pike and was of similar general layout, having three-bay wing bracing, a single fin and balanced rudder, and the simple but sturdy form of undercarriage first fitted to the Pike. The Type 529 was somewhat larger than its predecessor, however. Like the two Pikes, the 529 and 529A were made at Manchester and assembled at Hamble.
  The basic design was a handsome twin-engined tractor biplane which, m its 529A form, had a remarkably good performance. By the time the Avro 529 appeared, the Handley Page O/100 was in service; and the prototype O/400 was flying a few weeks before the 529A was flown. No doubt it was considered undesirable to interfere with O/400 production. However that may be, the Avro design did not proceed beyond the prototype stage.
  The 529 was first tested in April, 1917, but it was not until October of that year that the 529A appeared. The 529 and 529A differed principally in the type of engines fitted and in the arrangement of the fuel system. The 529 had two Rolls-Royce Falcon I engines developing 190 h.p. each, driving opposite-handed airscrews; the fuel was carried in a single large pressure tank immediately behind the pilot’s cockpit. The 529A had two 230 h.p. B.H.P. engines mounted directly on to the lower wings: the Falcons of the 529 were at the mid-gap position. The fuel system of the Avro 529A was designed to make each nacelle a self-contained unit: there was a 50-gallon tank in each nacelle, and from it fuel was pumped to a 10-gallon gravity tank directly above the engine. A small wind-driven pump was mounted on top of each nacelle. The two machines had slightly different elevator cable arrangements, and the 529A had a projecting bomb-aimer’s position under the nose. The wings could be folded.
  Elevator control on the type was described as poor, and the ailerons were said to be rather heavy. The rudder must have been effective, however, for both the 529 and 529A could be flown straight with one engine out of action. An unusual feature in a machine of this size was the dual control which was installed in the rear gunner’s cockpit. The bombs were carried internally, suspended by their noses, and were aimed and released by the bow gunner, who could communicate with the pilot by means of a speaking tube.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester; final assembly at Hamble works.
  Power: Avro 529: two 190 h.p. Rolls-Royce Falcons, engines Nos. 1/190/201 (port) and 1/190/8 (starboard). Avro 529A: two 230 h.p. B.H.P. (Galloway-built), engines Nos. £15435 and £15442. Dimensions: Span: 63 ft. Length: 39 ft 8 in. Height: 13 ft. Chord: 7 ft 6 in. Gap: 7 ft 3 in. Stagger: nil. Dihedral: 3. Incidence: 3. Span of tail: 18 ft. Wheel track: 12 ft 9 in. Tyres: 900 X 200 mm. Airscrew diameter (Avro 529): 9 ft 11 1/2 in.
  Areas: Wings: 922-5 sq ft. Ailerons: each 32-2 sq ft, total 128-8 sq ft. Tailplane: 48-4 sq ft. Elevators: 36-8 sq ft. Fin: 10 sq ft. Rudder: 24-5 sq ft.

  Weights (lb) and Performance without Bombs:
Avro 529 Avro 529A
No. of Trial Report M.110 M.155
Date of Trial Report June, 1917 November, 1917
Type of airscrew used on trial A. V. Roe, 4834 and 4824 -
Weight empty 4.376 -
Military load 273 273
Crew 540 540
Fuel and oil 1,120 -
Loaded 6,309 6,323
Maximum speed (m.p.h.) at
8,000 ft 94 -
10,000 ft 89 106
13,000 ft 81-5 -
14,000 ft 79'5 -
15,000 ft - 93

m. s. m. s.
Climb to
1,000 ft 1 25 - -
6,500 ft 11 25 9 50
10,000 ft 21 40 17 20
12,000 ft 31 05 - -
14,000 ft 48 05 - -
15,000 ft - - 35 05
Service ceiling (feet) 13,500 17,500
Endurance (hours) 5 5
Tankage :
Petrol 140 gallons in pres- Main:
sure tank in 2 X 50 gallons
fuselage Service:
2x10 gallons Total: 120 gallons
Oil 7 gallons per engine; -
total 14 gallons
Water 8 gallons per engine; -
total 16 gallons

  Armament: One Lewis machine-gun on a Scarff ring-mounting on front cockpit; a second Lewis gun on a Scarff ring-mounting was fitted to the cockpit aft of the wings. The bomb load of the Avro 529A could consist of twenty 50-lb bombs stowed internally within the fuselage, between the spars of the lower wing. The bombs were suspended by their noses.
  Serial Numbers: Avro 529: 3694. Avro 529A: 3695. Both machines were built under Contract No. C.P. 122495/16/X/23723.

Avro 530

  THE Avro 530 was one of the many promising designs of the war period which, for one reason or another, did not go into production. It was a two-seat fighter of advanced conception, and its performance compared quite well with that of early versions of the Bristol Fighter. However, by the time the Avro 530 appeared in July, 1917, the Bristol machine was already in production; moreover, at that time virtually all Hispano-Suiza engines were absorbed by the S.E.5a production programme.
  The Avro 530 was originally designed to have a 300 h.p. Hispano-Suiza engine but none was available at the time of completion of the airframe, and the prototype was fitted with the 200 h.p. Hispano-Suiza and the Sunbeam Arab. The components were made at the Manchester works of the Avro company and were sent to Hamble for assembly.
  The machine was characterised by commendably clean design. The Hispano-Suiza version had a large open-fronted spinner on the airscrew, and the radiator was installed behind it within the engine cowling. The deep fuselage completely filled the gap between the wings, and the central connexion between the fuselage and upper wing had a plywood fairing which also housed the pilot’s machine-gun. The upper wing was level with the pilot’s eyes, and he therefore had an excellent view all round the upper hemisphere. The observer’s cockpit was immediately behind the pilot’s in order to ensure maximum crew cooperation. The undercarriage legs, which were normal vees, were carefully faired over with fabric.
  The basic structure was conventional. The fuselage was the usual wire-braced wooden box-girder and had fairings on the sides. The engine was mounted on duralumin girders. The wings were made almost wholly of wood, but some metal was used in the construction of the ribs.
  The wings were of R.A.F. 14 section, and were fitted with trailing-edge flaps along the whole of their length between the ailerons and the fuselage: these flaps were actuated by a wheel control in the pilot’s cockpit. For comparative tests a second set of wings of R.A.F. 15 section were built without flaps.
  The version of the Avro 530 which had the Sunbeam Arab engine had no spinner; the undercarriage vees were much wider than those of the Hispano-powered version and were not faired over.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester; final assembly at Hamble works.
  Power: 200 h.p. Hispano-Suiza, engine No. 115034; 200 h.p. Sunbeam Arab.
  Dimensions: Span: 36 ft. Length: 28 ft 6 in. Height: 9 ft 7 in. Chord: 5 ft 6 in. Gap: 5 ft. Stagger: 1 ft 9in. Dihedral: 1° 30'. Incidence: 2°. Span of tail: 12 ft. Airscrew diameter: 9 ft 9 in.
  Areas: Wings: 325-5 sq ft. Ailerons: each 14-5 sq ft, total 58 sq ft. Tailplane: 28-4 sq ft. Elevators: 22-8 sq ft. Fin: 4-5 sq ft. Rudder: 8-8 sq ft.
  Weights: Empty: 1,695 Military load: 214 lb. Crew: 360 lb. Fuel and oil: 411 lb. Loaded: 2,680 lb.
  Performance: Maximum speed at ground level: 114 m.p.h.; at 10,000 ft: 102 m.p.h. Climb to 5,000 ft: 6 min 30 sec; to 10,000 ft: 15 min; to 18,000 ft: 40 min. Ceiling: 18,000 ft. Endurance: 4 hours at 10,000 ft.
  Tankage: Petrol: main tank 33 gallons, auxiliary 7 gallons; total 40 gallons.
  Armament: One fixed Vickers machine-gun mounted in the central fairing on top of the fuselage, and synchronised to fire forward through the revolving airscrew; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Production: One Avro 530 was built under Contract No. A.S.425/17/C.

Avro 533, the Manchester

  THE ultimate war-time expression of the Avro twin-engined bomber concept was given in the excellent Manchester design of 1918. Its descent from the Pike and the Avro 529 was clearly discernible, but the Manchester showed several structural and aerodynamic improvements over its predecessors. The fuselage was shorter and deeper, and provided better accommodation for the crew of three; the arrangement of the interplane struts was simplified; and the tail surfaces were of more pleasing outline. The ailerons were balanced in an unusual way. Instead of the more normal horn balance, each aileron had, mounted above and parallel to it, a small auxiliary aerofoil. Thus, any depression of an aileron increased the angle of attack of the small aerofoil and produced a balancing force; the opposite effect was obtained on a raised aileron. Construction of the Manchester was undertaken at the Avro company’s Hamble works.
  The Manchester was first designed early in 1918, at a time when great hopes were entertained for the A.B.C. Dragonfly radial engine, which was then going into production. The Manchester was therefore designed to have two Dragonflies, but as the aircraft neared completion it became evident that no engines were going to be available in time. To permit flight trials of the airframe, the first Manchester was modified to have Siddeley Puma engines and was designated the Avro 533A Manchester Mark II.
  The engines were two high-compression Pumas which delivered 300 h.p. each, and with them the Manchester II was tested in December, 1918. Dragonfly engines ultimately became available, and a true Manchester Mk. I was completed with two Dragonflies. This chain of circumstances accounts for the fact that the Mk. II had the earlier serial number F.3492, whilst the Mk. I was F.3493. The tail-unit of the Manchester Mk. I differed from that of the Mk. II. The area of all tail surfaces was appreciably increased in the Mk. I; the fin and rudder were taller; and the Mk. I had plain elevators whereas those of the Mk. II had inset horn balances. Both machines had balanced rudders. A third version was projected with twin Liberty engines but was never built. The third Manchester airframe was, however, completed.
  The Manchester appeared too late to go into production, but the performance of both Marks compared favourably with that of the more powerful D.H.10A, and bore testimony to the excellence of the design.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Hamble.
  Power: Manchester Mk. I: two 320 h.p. A.B.C. Dragonfly I. Manchester Mk. II: two 300 h.p. Siddeley Puma (high compression). Manchester Mk. Ill: two 400 h.p. Liberty (projected).
  Dimensions: Span: 60 ft. Length: 37 ft. Height: 12 ft 6 in. Chord: 7 ft 6 in. Gap: 7 ft 3 in. Stagger: nil. Dihedral: 2° 30'. Incidence: 40. Span of tail: 13 ft. Airscrew diameter: 2-9 metres.
  Areas: Wings: upper 430 sq ft; lower (Mk. I) 383 sq ft, (Mk. II) 387 sq ft: total (Mk. I) 813 sq ft, (Mk. II) 817 sq ft. Ailerons: each 31 sq ft, total 124 sq ft. Tailplane: (Mk. I) 69 sq ft, (Mk. II) 50 sq ft. Elevators: (Mk. I) 38 sq ft, (Mk. II) 35 sq ft. Fin: (Mk. I) 16 sq ft, (Mk. II) 12 sq ft. Rudder: (Mk. I) 18 sq ft, (Mk. II) 16 sq ft.

Weights {lb) and Performance:
Manchester Mk. I Manchester Mk. II
No. of Trial Report M.266 -
Date of Trial Report October, 1919 -
Weight empty 4,887 4’574
Military load 433 1,074
Crew 540 540
Fuel and oil 1,530 970
Weight loaded 7,390 7,158
Maximum speed (m.p.h.) at
ground level - 125
6,500 ft 114-5 -
10,000 ft 112 119
15,000 ft 103-5 112-5
m. s. m. s.
Climb to
5,000 ft - - 6 30
6,500 ft 8 20 - -
10,000 ft 14 20 16 30
15,000 ft 28 00 32 00
17,000 ft - - 43 00
Service ceiling (feet) 19,000 17,000
Endurance at 10,000 ft (hours) 5 3/4 3 3/4
Tankage: Petrol (gallons) 183 116

  Armament: Bomb load: 880 lb. One Lewis machine-gun on ScarfF ring-mounting on bow cockpit, one Lewis gun on similar mounting on rear cockpit aft of wings.
  Production: Three prototypes were built at Hamble.
  Serial Numbers: F.3492-F.3494 (F.3492 was the Manchester Mk. II, F.3493 was the Mk. I).

Avro 531, the Spider

  THE Avro Spider appeared in April, 1918. It was a compact little single-seat fighter in which numbers of Avro 504K components were used in order to ensure rapid and easy production. In fact, the complete front portion of the fuselage was identical to that of the 504K, and many of the small fittings were standard 504K components.
  The wing bracing was quite unlike anything used on any other contemporary British aeroplane. There were neither flying nor landing wires, but the structure was braced by a triangulated system of faired steel tubes. The lower wing was shorter than the upper, and was of unusually narrow chord: in this respect the wing arrangement resembled that of the Nieuport Scouts, and the lower wing seemed to be little more than part of the bracing for the upper mainplane. Spars were built-up spruce components, and the fuselage longerons and spacers were also spruce; the petrol tank was situated behind the cockpit. The undercarriage was a simple vee structure of faired steel tubes.
  Particular attention had been paid to achieving the best possible view for the pilot. To this end the upper wing was mounted very close to the fuselage, and a circular hole was cut in the centre-section: through this hole the pilot’s head protruded. The mainplane was level with his eyes, so that his view of the upper hemisphere could not have been better; and the forward and downward view was helped by the short nose and narrow lower wing.
  The Spider’s manoeuvrability was exemplary. During its trials it repeatedly outmanoeuvred contemporary standard scouts against which it was matched in mock combat. The Spider did not go into production, however, doubtless because of existing production programmes and the promise of other new types. It is also doubtful whether the fighter pilots of the Spider’s day would have welcomed a reversion to only one machine-gun as their armament.
  As originally built, the Spider was powered by a 110 h.p. Le Rhone rotary engine, but it seems fairly certain (as the quoted performance figures show) that a 130 h.p. Clerget was also fitted. It would have been a simple matter to make such an engine-change, in view of the use of the 504K front fuselage. According to Jane's All the World's Aircraft, 1919 edition, it was intended to fit later Spiders with the Bentley B.R.2 engine, but the estimated performance figures quoted for that engine were apparently based on a power output of 180 h.p. whereas the B.R.2 delivered 238 h.p.
  Another version of the design was given the Avro type number 531A, but it is uncertain whether the machine was ever completed. This variant was designed with normal biplane wings which had conventional interplane struts and wire bracing. The upper centre section was left completely open, as on the Sopwith Dolphin, but in the Avro 531A the pilot sat behind the rear spar instead of between the spars.


SPECIFICATION
  Manufacturers: A. V. Roe & Co., Ltd., Clifton Street, Miles Platting, Manchester, and at Hamble.
  Power: 110 h.p. Le Rhone; 130 h.p. Clerget.
  Dimensions: Span: upper 28 ft 6 in., lower 21 ft 6 in. Length: 20 ft 6 in. Height: 7 ft 10 in. Chord: upper 6 ft, lower 2 ft 6in. Gap: 4 ft 2 1/2 in. Stagger: 2 ft. Dihedral: nil. Incidence: nil. Span of tail: 8 ft 6 in. Chord of tailplane: 2 ft 8 in. Chord of elevators: 1 ft 6 in. Tyres: 700 X 78 mm.
  Areas: Wings: upper 144 sq ft, lower 45 sq ft, total 189 sq ft. Ailerons: each 11 sq ft, total 22 sq ft. Tailplane: 17-5 sq ft. Elevators: 11 sq ft. Rudder: 7-8 sq ft.

Weights (lb) and Performance:
130 h.p. Clerget Estimated figures for Bentley B.R.2
Weight empty 963 1,148
Military load 125 158
Pilot 180 180
Fuel and oil 249 248
Weight loaded 1,517 1,734
Maximum speed (m.p.h.)
at ground level 120 124
8,000 ft - 121
10,000 ft I 10 122
15,000 ft - i<5

m. s. m. s.
Climb to
3,500 ft - - 2 12
5,000 ft 4 00 - -
8,000 ft - - 5 00
10,000 ft 9 30 7 00
15,000 ft 22 00 13 30
18,000 ft - - 20 00
20,000 ft - - 26 00
Ceiling (feet) 19,000 -
Endurance at
10,000 ft (hours) - 2
15,000 ft (hours) - 2 1/2

  Tankage: Petrol: 26 1/2 gallons. Oil: 6 gallons.
  Armament: One fixed Vickers machine-gun mounted on top of cowling to starboard of centre, synchronised to fire forward through the revolving airscrew; 800 rounds of ammunition were carried.

SPECIFICATION OF AVRO 521A
  Power: 130 h.p. Clerget.
  Dimensions: Span: upper 28 ft, lower 27 ft. Length: 20 ft 6 in. Chord: 4 ft 6 in. Gap: 4 ft 3in. Stagger Dihedral: 2. Incidence: 1 30'.
  Areas: Wings: upper 106 sq ft, lower 104 sq ft, total 210 sq ft. Ailerons: each 7-3 sq ft, total 29-2 sq ft. Tailplane: 17.5 sq ft. Elevators: 11 sq ft. Rudder: 7-8 sq ft.
  Weights: Empty: 960 lb. Loaded: 1,514 lb.
  Performance: Maximum speed at ground level: 120 m.p.h.; at 10,000 ft: 110-5 m.p.h.; at 15,000 ft: 103 m.p.h. Climb to 5,000 ft: 4 min; to 10,000 ft: 9 min 30 sec; to 15,000 ft: 22 min. Ceiling: 19,000 ft. Endurance: 3 hours.
  Serial Numbers: It is believed that the serial numbers B.3952-B.3953 were allotted for Avro Spiders.

B.A.T. F.K.22 and F.K.23 Bantam

  THE British Aerial Transport Co. was founded in 1917 by Samuel (later Lord) Waring, and the new concern took over premises in Hythe Road, Willesden, previously occupied by the Joucques Aviation Co. The firm’s chief designer was Frederick Koolhoven, who had left Sir W. G. Armstrong, Whitworth & Co., Ltd., to join the B.A.T. Co.; and the first aircraft built to his design by his new firm was the F.K. 22, a small single-seat fighter which was appropriately named the Bat.
  The F.K.22 embodied some features which became characteristic of the Koolhoven-designed B.A.T. types, but which were regarded as unconventional in Britain. The fuselage was a wooden monocoque and the fin was built integral with it; the birch three-ply skin was applied to ash formers, and the cross-section was a near-ellipse. The pilot sat with his head protruding through a circular hole in the upper centre-section, which was attached directly to the fuselage. Each wing was made in three parts, all approximately equal in length. The spars were of spruce, and the underside of the lower centre-section was covered with birch three-ply. Only the outer panels of the mainplanes had dihedral, and ailerons were fitted to both upper and lower wings. Wooden interplane struts were used.
  The undercarriage was of the divided-axle type which was used on all subsequent B.A.T. types of the war period: in the F.K. 22 it occupied the complete width of the lower centre-section. The vees were built up of seven laminations of spruce, and incorporated vertical coil springs for shock absorbers. The undercarriage therefore had a wide track and independently sprung wheels. The rudder had a horn balance.
  The power unit for which the F.K. 22 was designed was the 120 h.p. A.B.C. Mosquito. This was a six-cylinder air-cooled radial engine. Unfortunately for the B.A.T. F.K. 22, the Mosquito proved to be unsuccessful in its bench tests.
It seems that, about the time when the F.K.22 airframe was complete and the failure of the A.B.C. Mosquito was known, it was decided to modify the design to take a later and more powerful A.B.C. radial engine which had appeared. This engine was the Wasp, a seven-cylinder radial of 170 h.p. The modified aircraft was renamed the Bantam. The A.B.C. Wasp was designed by Granville Bradshaw and was submitted to the Government in October, 1917. The engine was designed for ease of production, and performed quite well on its early trials, for it gave 170 h.p. for a weight of only 290 lb. Its early success (although enough to encourage its designer to press his newer design, the Dragonfly, upon the Government) was not continued.
  However, the original F.K.22 airframe was flown, powered by rotary engines. Fitted with a 100 h.p. Gnome Monosoupape, an F.K.22 was tested at Martlesham Heath in February, 1918, and the machine numbered B.9945 was also flown with a 110 h.p. Le Rhone. Official documents refer to the Gnome-powered version as the Bantam Mark II, presumably on the analogy of such designations as the Avro Manchester Mk. II and Sopwith Cobham Mk. II. The designation Bantam Mk. I was applied to the Wasp-powered machine.
  The analogy was not complete, however, for the relationship between Bantams Mk. II and Mk. I was much less close than the relationship between the corresponding marks of Manchester and Cobham. The Bantam Mk. I was in fact a new design and was given a new type number, F.K.23, by its designer. When the first Bantam Mk. I appeared, it differed markedly in appearance from the F.K.22 as exemplified by B.9945.
  The new machine was considerably smaller than the F.K.22, and the wing area was greatly reduced. Again the upper wing was attached directly to the fuselage and there was a hole for the pilot’s head and shoulders, but the wing was made in one piece and was quite flat. The lower wings alone had dihedral and were attached to a centre-section of short span. As on the F.K.22, wooden interplane struts were fitted. The vee-struts of the undercarriage were directly under the inner interplane struts.
  A monocoque fuselage of new design and good aerodynamic form was used. Its basic structure consisted of four ash longerons bearing spruce formers round which sheets of plywood were wrapped. The low aspect-ratio triangular fin was built integral with the fuselage, and the rudder was a plain surface with a straight vertical trailing edge.
  The monocoque fuselage was officially viewed with some suspicion. Although many contemporary German aeroplanes had fuselages built on that principle, the idea was still regarded as somewhat revolutionary in Britain at the time of the Bantam’s appearance.
  The Bantam B.9947 was at Hendon in February, 1918. Unfortunately, the type proved to have disastrous spinning characteristics. The gap was narrow because the upper wing had been placed on top of the fuselage in order to give the pilot the best possible view; there was no stagger; the centre of gravity was rather far aft; and the stubby little fuselage gave a comparatively short moment arm for the fin and rudder.
  The Bantam’s spin began at a normal speed but rapidly accelerated until it reached a phenomenal rate of autorotation, from which it could be brought out only by vigorous use of the controls. Accidents occurred with Bantams owing to their spinning characteristics. Major Christopher Draper, one of the most noted exponents of the type, spun into the ground at Hendon in one of the prototypes. He survived the crash, thanks to the great strength of the Bantam’s fuselage, which came out of the crash remarkably well.
  After a second accident had occurred in which a Bantam had spun into the ground, the Accidents Investigation Sub-committee of the Aeronautical Research Committee requested that experiments be conducted to determine the cause of the crashes. It was shown that the Bantam’s unusual behaviour in a spin was attributable chiefly to the position of the centre of gravity which, at 42 per cent chord, was too far aft; and to the combination of zero stagger with an unusually small gap/chord ratio (0,81).
  However, the Bantam was fast and highly manoeuvrable, and a small production batch was ordered. The production machines had a re-designed wing structure and a revised tail-unit: enlarged horizontal surfaces were fitted, the rudder was increased in area, and there was a corresponding reduction in the area of the fin. The new wings were of greater span and area, and both were given equal dihedral angles. The interplane struts were of steel tube. This version, which was the best-known form of the design, had the same type number F.K.23.
  These modifications did much to cure the trouble, and the Bantam did well in all its Service trials. Only nine production Bantams, numbered F.1653 to F. 1661, were built, however. The A.B.G. Wasp was noted for its capricious behaviour, and it was decided not to proceed further with the production of that engine. Deprived of its power unit, the Bantam had perforce to be withdrawn from production also.
  A single Bantam fuselage was built for the Admiralty and was exposed for several months on Inverkeithing Dock to test its resistance to widely varying climatic conditions. When returned to the works for inspection the fuselage was found to have suffered very little deterioration.
  Shortly after the war, Lord Waring felt obliged to reduce his aviation interests and the B.A.T. company was virtually disbanded, although technically it was amalgamated with the Alliance Aeroplane Co., Ltd., of Acton, and the British Nieuport & General Aircraft Co., Ltd., of Cricklewood, two other concerns which had been founded by Lord Waring.
In the meantime, one of the Bantams had been fitted with the more powerful A.B.C. Wasp II, which delivered 200 h.p. After the merger of the firms, this machine was put through a series of trials by Captain L. R. Tait-Cox, the Nieuport test pilot. The top speed was increased to 146 m.p.h. at 10,000 feet, and the rate of climb was correspondingly improved.
  At least one Bantam went to America, where it was flown at Wright Field with American markings. Its American serial number was A.S.94111, and it bore the Wright Field Project Number P.167 on the rudder.
  Seven Bantams went on to the British Civil Register after the Armistice. They were registered K.123 (later G-EACN), K.125 (G-EACP), K.154 (G-EAFM), K.155 (G-EAFN), G-EAJW, G-EAMM and G-EAYA. K.123 and K.125 were entered in the 1919 Aerial Derby, in which they were flown by Clifford Prodger and Major Draper. K.125 had its lower wing clipped just outboard of the inner bay of interplane struts, the extensions of the upper mainplane being braced by long struts.
  In 1924 G-EAYA (formerly F.1661) was bought by Frederick Koolhoven and was taken by him to Holland. There it was fitted with a 200 h.p. Armstrong Siddeley Lynx engine, and was said to have attained a speed of 246 km/hr (about 154 m.p.h.).


SPECIFICATION
Dimensions:
Bantam Mk. II (Gnome) Bantam Mk. I prototype Production
Bantam
Span 24 ft 8 in. 20 ft 25 ft
Length 20 ft 8 in. - 18 ft 5 in.
Height 7 ft 5 in. - 6 ft 9 in.
Chord 4 ft 11 in. 4 ft 3 ft 11 1/4 in.
Gap 4 ft 3 in. 3ft 3ft 3 1/2 in
Stagger Nil Nil Nil
Dihedral, upper 2° Nil 2° 30'
Dihedral, lower 2° 2° 2° 30'
Incidence, upper 2° 2° -
Incidence, lower 2° 2° -
Span of tail 6 ft 6 in. 6 ft 7 in. 9 ft 2 in.
Wheel track - - 7 ft 2 1/2 in.
Airscrew diameter - - 7 ft 10 1/2 in.
Areas (sq ft):
Wings 230 160 185
Ailerons: each 6 3-8 4-5
total 24 15-2 18
Tailplane 7 10-4 16-7
Elevators 10-5 5-85 6-3
Fin 2-5 3-5 2-85
Rudder 6 3-85 4-4

Weights (lb) and Performance:
Bantam Mk. II (Gnome) Bantam Mk. I (production)
   Wasp I Wasp II
No. of Trial Report M.175 M.242 -
Date of Trial Report February, 1918 October, 1918 -
Type of airscrew used on trial P.3012 I.P.C.2414 -
Weight empty 866 833 -
Military load 50 130 -
Pilot 180 180 -
Fuel and oil 164 178 -
Weight loaded 1,260 1,321 -
Maximum speed (m.p.h.) at
6,500 ft - 128 -
10,000 ft 100 125-5 146
15,000 ft - 118 -
m. s. m. s. m. s.
Climb to
6,500 ft 9 05 5 10 - -
10,000 ft 16 50 9 00 - -
15,000 ft 43 00 17 05 - -
17,000 ft - - - - 16 00
Service ceiling (feet) 14,500 20,000 -
Endurance (hours) - 2 1/4 -
Tankage: Petrol (gallons) 17 22 -

  Manufacturers: The British Aerial Transport Co., Ltd., Hythe Road, Willesden, London, N.W.
  Power: Bantam Mk. I: 170 h.p. A.B.C. Wasp I; 200 h.p. A.B.C. Wasp II. Bantam Mk. II: 100 h.p. Gnome Monosoupape; 110 h.p. Le Rhone.
  Armament: Two fixed Vickers machine-guns mounted low down on either side of the fuselage, firing between the lowest pair of cylinders on each side, and synchronised to fire forward through the revolving airscrew (i.e., on production Bantams).
  Service Use: Only one B.A.T. aeroplane was delivered to a Training Unit during 1918. In February, 1918, the Bantam Mk. II, B.9945 was at Hounslow, and the Mk. I prototype, B.9947 was at Hendon. On October 31st, 1918, the R.A.F. had three unspecified B.A.T.s on charge: one was at an Aircraft Acceptance Park and two were at testing units. One production Bantam Mk. I went to America.
  Serial Numbers: B.9944-B.9949: ordered under Contract No. A.S.25314. F.1653-F.1661.

B.A.T. F.K.24, Baboon

  THE Baboon was a small two-seat training biplane, in the design of which Koolhoven had aimed at ease of production and interchangeability of components. The fuselage was a very simple box structure with a rounded top-decking which was the only concession to aesthetics or aerodynamics in the entire design. The fuselage was considerably strengthened by its plywood covering. The A.B.C. Wasp radial engine was mounted on the flat-nose bulkhead and was innocent of any pretence at fairing; the interplane and centre-section struts were plain steel tubes without fairings; and all flight surfaces were straight-edged and square-cut. The undercarriage was the same wide-track, split-axle type used on the Bantam.
  Interchangeability of components was held to be a desirable feature of trainer aircraft, which could be expected to suffer more damage than other types. Koolhoven, with typical ingenuity, carried the idea almost to its extreme in the Baboon: not only were the upper and lower mainplanes interchangeable, but the ailerons, elevators and rudder were all identical surfaces.
  The Baboon was not officially adopted, but survived the Armistice and went on the British Civil Register as G-EACO.


SPECIFICATION
  Manufacturers: The British Aerial Transport Co., Ltd., Hythe Road, Willesden, London, N.W.
  Power: 170 h.p. A.B.C. Wasp I.
  Dimensions: Span: 25 ft. Length: 22 ft 8 in. Height: 8 ft 10 in. Chord: 5 ft yin. Gap: 4 ft 8 1/2 in. Stagger: nil. Dihedral: 2. Span of tail: 9 ft 10 in. Airscrew diameter: 7 ft 10 in.
  Areas: Wings: 259 sq ft. Ailerons: each 6 sq ft, total 24 sq ft. Tailplane: 15-75 sq ft. Elevators: 12 sq ft. Fin: 5-25 sq ft. Rudder: 6 sq ft.
  Weights: Empty: 950 lb. Disposable load: 400 lb.
  Performance: Maximum speed at ground level: 90 m.p.h. Climb to 10,000 ft: 12 min. Endurance: 2 hours.
  Tankage: Petrol: 12 gallons.
  Armament: None.
  Serial Numbers: D.9731-D.9736. It is believed that only D.9731 was built.

B.A.T. F.K.25, the Basilisk

  THE stumpy little Basilisk was built in 1918. It was a single-seat fighter developed from the Bantam, and was fitted with the more powerful A.B.C. Dragonfly I radial engine of 320 h.p.
  Once again Koolhoven produced a machine having a wooden monocoque fuselage, two-bay wings of equal span, and the typical wide-track undercarriage with independent springing of each wheel. In the Basilisk the wing and cockpit arrangements were more conventional than those of the Bantam. The upper wing was made in two halves which were connected to the fuselage by a single N-strut on the aircraft’s centre-line. The pilot sat behind and slightly below the upper wing. Only the lower wing was rigged with dihedral. On the first prototype, F.2906, plain ailerons were fitted to upper and lower wings, but the second Basilisk had horn-balanced ailerons. The later machine also had a larger fairing over the machineguns.
  Some rather exaggerated claims have been made for the Basilisk’s performance, and figures quoting a speed of 162 m.p.h. at ground level have gained some credence. The performance details given below come from a Martlesham Heath test report dated October, 1919, and are probably much more realistic. It will be seen that the performance was still very good, however. The Basilisk suffered (as did so many of its contemporaries) from the shortcomings of its A.B.C. Dragonfly engine. The Dragonfly was developed from August, 1917, onwards, and seemed to hold such promise that large-scale production was ordered in 1918. It is therefore not surprising that so many prototype aircraft of that year were fitted with the Dragonfly. This engine is discussed in the history of the Nieuport Nighthawk.
  One of the Basilisks crashed in 1919, killing its pilot, Peter Legh, who had been one of the B.A.T. team of test pilots.
  

SPECIFICATION
  Manufacturers: The British Aerial Transport Co., Ltd., Hythe Road, Willesden, London, N.W.
  Power: 320 h.p. A.B.C. Dragonfly I.
  Dimensions: Span: 25 ft 4 in. Length: 20 ft 5 in. Height: 8 ft 2 in. Chord: 4 ft 6 1/2 in. Gap: 4 ft 4 in. Stagger: nil. Span of tail: 9 ft 10 in. Airscrew diameter: 8 ft 8 in.
  Areas: Wings: 212 sq ft. Ailerons: each 7-5 sq ft, total 30 sq ft. Tailplane: 13-7 sq ft. Elevators: 8-3 sq ft. Fin: 2-6 sq ft. Rudder: 4-5 sq ft.
  Weights and Performance: No. of Trial Report: M.267. Date of Trial Report: October, 1919. Type of airscrew used on trial: A.B.9331. Weight empty: 1,454 lb. Military load: 218 lb. Pilot: 180 lb. Fuel and oil: 330 lb. Weight loaded: 2,182 lb. Maximum speed at 6,500 ft: 142-5 m.p.h.; at 10,000 ft: 141 m.p.h.; at 15,000 ft: 135 m.p.h. Climb to 6,500 ft: 4 min 50 sec; to 10,000 ft: 8 min 25 sec; to 15,000 ft: 15 min 5 sec. Service ceiling: 22,500 ft. Endurance: 3 1/4 hours.
  Tankage: Petrol: 40 gallons.
  Armament: Two fixed and synchronised Vickers machine-guns mounted on top of the fuselage, firing forward. These guns were slightly staggered: the port gun was a few inches forward of the starboard.
  Serial Numbers: F.2906-F.2908. At least two, F.2906 and F.2907, were built.

Beardmore W.B.I

  THE well-known engineering and ship-building firm of William Beardmore & Co. entered the aircraft industry shortly before the outbreak of war in 1914, when they obtained a licence to build the German D.F.W. biplane, which was to be powered by the Beardmore-built Austro-Daimler engine. As war came closer, Beardmores were among the first firms to be awarded contracts for the manufacture of the B.E.2c, and throughout the war large numbers of aircraft of various types were built at Dalmuir.
  In September, 1914, G. Tilghman Richards went to Beardmores as a Lieutenant, R.N.V.R., attached to the R.N.A.S. He, in common with several others who had had some experience of aircraft construction, was commissioned and classed as one of H.M. Inspectors of Naval Aircraft when the outbreak of war stopped the production of non-military aircraft. Up till then Mr Richards had played a leading part in the development of the Lee-Richards Annular Monoplane.
  In early 1916 the Admiralty began to encourage contracting firms to undertake original design work and, in the case of Beardmores, allowed Mr Richards to resign his commission in order to become the firm’s chief designer and assistant manager of their Aviation Department.
  The first Beardmore aeroplane was designated W.B.I, and construction began in 1916. It was a large two-seat single-engined biplane, designed as a long-range bomber. It was intended to deliver surprise attacks by long glide approaches on to its targets, and to this end Mr Richards paid particular attention to endowing the W.B.I with the best possible gliding angle. The nose was carefully streamlined, the three-bay wings were of fairly high aspect-ratio and were heavily staggered; and despite its large side radiators and complex undercarriage the W.B.I’s gliding angle was about i in 15.
  The observer acted as bomb-aimer. His cockpit was situated well aft and had an aperture in the floor, through which the bombs were sighted. A visual type of intercommunication equipment linked the observer and pilot: it was a two-way system not very different from a ship’s engine-room telegraph.
  The W.B.I was delivered to the R.N.A.S. and was flown with both the 230 h.p. Beardmore Adriatic and 240 h.p. Sunbeam engines. By the time of its appearance, however, the Handley Page O/100 was becoming available and held out the promise of carrying greater bomb loads at comparable speeds. The W.B.I was not adopted for Service use.
  The machine’s “quadricycle” undercarriage and clean design contributed to a crash when it was being flown by Wing-Commander R. E. C. Peirse at Cranwell in 1917: a*- the time the W.B.I had the Sunbeam engine. After landing well out on the aerodrome, the machine rolled on, tail up, and crashed into two B.E.2c’s parked on the tarmac. The B.E.2 suffered most of the resulting damage, but the W.B.I was not flown again at Cranwell.
  A development with the 500 h.p. B.H.P. Atlantic engine was projected under the designation W.B.IA. In it the wing span was increased to 70 ft and the area to 946 sq ft; there were to be four bays of interplane struts. The pilot and observer were accommodated well aft: in fact, the fin blended with the fairing round the observer’s gun-ring. The estimated maximum speed at 10,000 ft and at a loaded weight of 8,900 lb was 101 m.p.h.


SPECIFICATION
  Manufacturers: William Beardmore & Co., Ltd., Dalmuir, Dumbartonshire.
  Power: 230 h.p. Beardmore (Galloway) Adriatic (the version of the 230 h.p. B.H.P. engine built by the Galloway Engineering Co.); or 240 h.p. Sunbeam.
  Dimensions: Span: 61 ft 6 in. Length: 32 ft 10 in. Height: 14 ft 9 in. Chord: 7 ft. Gap: 7 ft. Span of tail: 18 ft. Airscrew diameter: 10 ft 6 in.
  Areas: Wings: 796 sq ft. Ailerons: each 28-32 sq ft, total 113-28 sq ft. Tailplane: 66 sq ft. Elevators: 40 sq ft. Fin: 14-2 sq ft. Rudder: 20 sq ft.
  Weights (Beardmore Engine): Weight empty: 3,410 lb. Disposable load: 1,100 lb. Fuel and oil: 1,090 lb. Weight loaded: 5,600 lb.
  Performance (Beardmore Engine): Maximum speed at ground level: 91 m.p.h. Climb to 5,000 ft: 26 min; to 10,000 ft: 44 min. Endurance: 7-3 hours.
  Tankage: Petrol: 137 gallons.
  Armament: Six 110-lb bombs. Provision was made for the fitting of a ring-mounting on the rear cockpit for a free Lewis machine-gun.
  Service Use: Flown experimentally at R.N.A.S. Station, Cranwell.
  Serial Number: The official serial number N.525 was allotted to a Beardmore design which may have been the W.B.I.

Beardmore W.B.II

  THE second Beardmore type designed by Tilghman Richards was developed by him from the B.E.2C, for which type Beardmores were contractors to the Admiralty. Mr Richards wanted to show what the design was capable of, given a more powerful engine and an aerodynamically clean fuselage. Official permission was given for the construction of a prototype, and the resulting aircraft was a marked improvement over the B.E.2C. It was named Beardmore W.B.II.
  The only B.E. components which in fact were used were the mainplanes and interplane struts. The fuselage was faired to a circular cross-section, and the airscrew originally had a large open-fronted spinner. The engine was a 200 h.p. Hispano-Suiza. The clean lines of the fuselage were somewhat marred by the exhaust stacks and radiators: these were disposed in two elements mounted in an inverted vee just behind the forward cabane struts. Petrol was carried in two 21-gallon tanks installed behind the engine, and the oil tank was mounted externally below the engine.
  The undercarriage had two half-axles pivoted Sopwith-fashion at the mid-point of the two steel spreader-bars which connected the two plain vee-struts. A four-bladed airscrew was used at first, but was later replaced by a two-blader.
  The method of actuating the elevators was interesting and unusual at a time when the almost universal medium was wire cable. Control rods were used, and each elevator had one control horn only, on its lower surface.
  Whereas the observer of the B.E.2c occupied the forward seat, the W.B.II accommodated him behind the pilot where he could make effective use of his gun. The observer’s gun-mounting on the W.B.II was designed by Mr Richards, and gave a greater field of fire than the then-standard Scarff ring-mounting. The Beardmore-Richards mounting consisted of a “witch’s broomstick” built up of channel-section duralumin, pivoting on a ball joint at the centre of the cockpit floor and with its upper end running round the ring which surmounted the cockpit. The gunner’s seat was fixed half-way up the “stick”, which could thus be swung round instinctively and easily, and was provided with an instantaneous lock. The upper end of the “stick” carried the gun-mounting proper, which had a further range of movement: it could be swung upwards to enable the gun to fire vertically, or outwards when, with the “stick” athwartships, a line of fire could be obtained fifteen degrees past the centre-line of the aircraft in a downwards direction. Thus the normal blind spot was virtually eliminated.
  By December, 1917, several modifications had been made to the W.B.II. The engine was moved forward and the spinner discarded; the nose cowling was given a rounded contour. The gun-ring on the observer’s cockpit was raised 5 1/2 inches, which made it more comfortable and effective in use. Aluminium tanks replaced the original steel ones.
  The W.B.II was tested at Port Victoria and at Martlesham Heath, and was well reported on. It was said to be manoeuvrable and easy to land.
  The type did not go into production, but a development was projected with the 230 h.p. B.H.P. engine. This machine was designated W.B.IIA, and was to have been a fighter-reconnaissance two-seater with considerably increased fuel capacity. The speed was expected to be 125 m.p.h. at sea level and 117 m.p.h. at 10,000 feet.
  A further development known as the WB.IIB was built as an air-mail transport. Two machines, registered G-EARX and G-EARY were built, and participated in the Air Ministry competition for civil aircraft, held at Martlesham Heath in August, 1920. The Beardmore company initiated a Renfrew-London air-mail service with these machines, but it was short-lived.


SPECIFICATION
  Manufacturers: William Beardmore & Co., Ltd., Dalmuir, Dumbartonshire.
  Power: 200 h.p. Hispano-Suiza, engine No. (Peugeot) 115014.
  Dimensions: Span: 34 ft 10 in. Length: 26 ft 10 in. Height: 10 ft. Chord: 5 ft 6 in. Gap: 5 ft 6 in. Stagger: 2 ft. Dihedral: 1° 30'. Incidence: 1° 30'. Span of tail: 13 ft 6 in. Wheel track: 5 ft. Tyres: 750 X 125 mm. Airscrew diameter: 9 ft 6 1/2 in.
  Areas: Wings: 354 sq ft. Ailerons: each 16 sq ft, total 64 sq ft. Tailplane: 27-5 sq ft. Elevators: 20-2 sq ft. Fin: 6 sq ft. Rudder: 11-5 sq ft.
  Weights and Performance: Date of Trial Report: December, 1917. Type of airscrew used on trial: Lang 3500A, Series No. L/14104. Weight empty: 1,765 lb. Military load: 185 lb. Crew: 360 lb. Fuel and oil: 340 lb. Loaded: 2,650 lb. Maximum speed at ground level: 120 m.p.h.; at 10,000 ft: 111-5 m.p.h.; at 13,000 ft: 107 m.p.h. Climb to 1,000 ft: 1 min 15 sec; to 2,000 ft: 2 min. 35 sec; to 5,000 ft: 7 min; to 8,000 ft: 12 min 30 sec; to 10,000 ft: 14 min 40 sec; to 12,000 ft: 22 min 40 sec; to 13,000 ft: 26 min 10 sec; to 14,000 ft: 30 min 10 sec. Service ceiling: 17,000 ft. Endurance: 2,8 hours.
  Tankage: Petrol: 42 gallons. Oil: 4 1/2 gallons. Water: 8 gallons.
  Armament: Two fixed, synchronised Vickers machine-guns firing forward. One free Lewis machine-gun on Beardmore-Richards mounting in rear cockpit.
  Production: One prototype was built under Contract No. A.S.2864/18.

Beardmore W.B.III (S.B.3D)

  BEARDMORES were the first manufacturers to build the Sopwith Pup under licence. The earliest production Pups were built under Admiralty contracts for delivery to the R.N.A.S., and soon proved their worth in action.
  In February, 1917, the Grand Fleet Aircraft Committee recommended that the Sopwith Baby seaplanes carried by H.M.S. Campania should be replaced by Pups. A few Pups were sent to the ship for experimental work, and from that time onwards Pups were flown from various types of warship.
  With the initiation of shipboard flying, attention was at once focused on the desirability of saving stowage space on board ship. Beardmores therefore undertook the task of redesigning the Pup so that it would fold up, and so thorough was the reconstruction of the aeroplane that not only did the wings fold, but the undercarriage could also be “retracted” into the bottom of the fuselage; it was, however, a normal vee type when extended. In the event of an emergency landing at sea, the complete undercarriage could be jettisoned. Emergency flotation gear was fitted.
  The modified machine bore the Beardmore type number W.B.III. The most noticeable difference between the Pup and the W.B.III was that the wings of the latter had no stagger and reduced dihedral. Instead of the normal centre-section struts of the Pup, the W.B.III had four full-length interplane struts connecting the upper and lower centre-sections: these struts were joined to the upper longerons by transverse struts.
  The prototype W.B.III was a converted Pup which had the official serial number 9950: it was the last machine of a batch of fifty Pups which were built by Beardmores for the Admiralty. On the prototype, interplane struts were fitted at the inboard ends of the wings; they preserved the bracing truss when the wings were folded. The ailerons were actuated by a system of control rods: upright rods from the cockpit were attached to bell-cranks in the upper centre-section, and the cranks moved long horizontal rods running along the rear spar of the upper wings. Upper and lower ailerons were linked by light struts. Skids were fitted under the lower wing-tips, and could be folded up against the underside of the wings. The W.B.Ill’s fuselage was about a foot longer than that of the Pup.
  Production was undertaken on a modest scale. The early production W.B.Ills resembled the prototype, having the additional interplane struts at the inboard ends of the wings and the rod-operated ailerons. Later aircraft had only a cable connecting the inboard ends of the upper and lower mainplanes, the wingtip skids were discarded, and a simpler and more conventional cable-operated aileron control system was fitted. The standard engine was the 80 h.p. Le Rhone, but some machines may have had the 80 h.p. Clerget.
  There are indications that two different forms of undercarriage may have been fitted; one capable of being jettisoned only, the other capable only of folding. The official designation S.B.3D was applied to the former version of the W.B.Ill, the suffix D denoting “Dropping undercarriage”; the second form was known as the S.B.3F, the F signifying “Folding undercarriage”.
  The W.B.Ill saw service as part of the equipment of some of the early aircraft carriers: at one time H.M.S. Furious had as many as fourteen W.B.IIIs. According to Jane’s All the World’s Aircraft, 1920 edition, Japan had a few on the strength of her Naval Air Service.


SPECIFICATION
  Manufacturers: William Beardmore & Co., Ltd., Dalmuir, Dumbartonshire.
  Power: 80 h.p. Le Rhone 9C; 80 h.p. Clerget.
  Dimensions: Span: 25 ft. Length: 20 ft 2 1/2 in. Height: 8 ft 1 1/4 in. Chord: 5 ft 1 1/2 in. Gap: 4 ft 9in. Stagger: nil. Span of tail: 10 ft 1 in. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: 243 sq ft. Ailerons: each 5-75 sq ft, total 23 sq ft. Tailplane: 23 sq ft. Elevators: 11-5 sq ft. Fin: 3-5 sq ft. Rudder: 4-5 sq ft.
  Weights: Empty: 890 lb. Military load: 55 lb. Pilot: 180 lb. Fuel and oil: 164 lb. Weight loaded: 1,289 lb.
  Performance: Date of Trial Report: January 12 th, 1918. Maximum speed at ground level: 103 m.p.h.; at 6,500 ft: 98 m.p.h.; at 10,000 ft: 91 m.p.h. Climb to 5,000 ft: 9 min; to 6,500 ft: 12 min 10 sec; to 10,000 ft: 24 min 20 sec. Service ceiling: 12,400 ft. Endurance: 2 3/4 hours.
  Tankage: Petrol: 18 gallons.
  Armament: The prototype had a vertically-mounted Lewis machine-gun firing upwards through an aperture in the centre-section. Production W.B.IIIs had a Lewis gun mounted above the centre-section to starboard of centre, firing forwards and slightly upwards over the airscrew.
  Service Use: Aircraft carriers H.M.S. Furious, Nairana, Pegasus.
  Production and Allocation: Serial numbers were allotted for 100 Beardmore W.B.IIIs. On October 31st, 1918, fifty-five were on charge with the R.A.F. Of that total, eighteen were with the Grand Fleet; the remainder were in store.
  Serial Numbers: 9950 (converted Pup); N.6100-N.6129; N.6680-N.6749.

Beardmore W.B.IV

  THE Beardmore W.B.IV was a single-seat fighter intended for use from ships, and much ingenuity had been exercised to meet the requirements of its conditions of service. The design incorporated some remarkably advanced thinking, and in many ways the machine was ahead of its time. It appeared towards the end of 1917.
  The most striking engineering feature of the W.B.IV was the engine installation. The 200 h.p. Hispano-Suiza engine was mounted within the fuselage and directly above the lower wing: it drove the airscrew by an extension shaft. The pilot sat in front of the wings in a high, water-tight cockpit from which he must have had an excellent outlook in all forward and upward directions. The airscrew shaft passed between the pilot’s legs. The radiator was mounted between the rear centre-section struts. The fuselage itself was unusual, for it was covered with plywood.
  This engine installation with its long extension shaft is of great historical interest, for it antedated the Westland F.7/30 by quite fifteen years and the American Bell P.39 and P.63 by twenty years: all of these later types had extension shaft drives with the pilot well forward.
  In the Beardmore W.B.IV further advantage was taken of the rearward position of the engine to build a large buoyancy chamber into the bottom of the forward portion of the fuselage. This chamber projected on either side of the fuselage in the shape of an elongated blister. The undercarriage could be jettisoned if the aircraft were forced to alight on the sea, and when the W.B.IV first appeared it had a float under each lower wing-tip to assist in stabilising the aircraft when on the water. The W.B.IV could float on an even keel, thanks to the position of the engine on the centre of gravity. The wings could be folded. They were of unequal span and chord, and ailerons were fitted to the upper mainplanes only.
  The W.B.IV was delivered to the Isle of Grain station of the R.N.A.S., and there it was literally tested to destruction. It was flown without the wing-tip floats, and may have been used in experiments in alighting on the sea. Whatever the reason, the strenuous endeavours of the Grain pilots ultimately resulted in stoving-in the flotation chamber and the W.B.IV sank. Thus was lost one of the most interesting and advanced aircraft of the 1914-18 war.


SPECIFICATION
  Manufacturers: William Beardmore & Co., Ltd., Dalmuir, Dumbartonshire.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: 35 ft 10 in. Length: 26 ft 6 in. Height: 9 ft 10 1/2 in. Chord: upper 6 ft 3 in., lower 4 ft 9in. Gap: 4 ft 9 in. Span of tail: 11 ft 9 in. Airscrew diameter: 9 ft.
  Areas: Wings: 350 sq ft. Ailerons: each 18-8 sq ft, total 37-6 sq ft. Tailplane: 26-5 sq ft. Elevators: 24 sq ft. Fin: 8 sq ft. Rudder: 12 sq ft.
  Note: The values for the weights and times of climb are from Trial Report No. M.218, dated July, 1918.
  Weights: Empty: 2,055 lb. Military load: 91 lb. Pilot: 180 lb. Fuel and oil: 269 lb. Weight loaded: 2,595 lb.
  Performance: Maximum speed at ground level: 110 m.p.h.; at 10,000 ft: 102 m.p.h. Climb to 5,000 ft: 7 min;
to 6,500 ft: 9 min 40 sec; to 10,000 ft: 18 min 20 sec. Service ceiling: 14,000 ft. Endurance: 2 1/2 hours.
  Tankage: Petrol: 37 gallons.
  Armament: One fixed, synchronised Vickers machine-gun mounted on the port side below the upper longeron and with its breech within the fuselage; one upward-firing Lewis machine-gun on tripod above the windscreen.
  Production: Three W.B.IVs were ordered but only one was built.
  Serial Numbers: N.38-N.40 (N.39 and N.40 were not built).

Beardmore W.B.V

  CONTEMPORARY with the Beardmore W.B.IV was the W.B.V, which was also a single-seat fighter built for the R.N.A.S. In appearance and design it was more conventional than the W.B.IV.
  The wings were of equal chord, and the upper mainplanes appeared to be identical to those of the W.B.IV. The wings could be folded. The pilot sat under the upper centre-section; and the plywood- covered fuselage was of conventional appearance. The tail-unit resembled that of the W.B.IV. The same rudder was used, but both upper and lower fins were extended forward a short distance. The undercarriage was very similar to that of the W.B.IV, and could be jettisoned. Emergency flotation gear was provided in the form of inflatable air bags which lay along the underside of the leading edge of the lower wing.
  As required by the Admiralty specification, the W.B.V was designed round a 37 mm Canon Puteaux, a large-calibre quick-firing gun which was mounted in the vee of the cylinder banks of the 200 h.p. Hispano-Suiza engine. The muzzle of this gun passed through the hollow airscrew shaft, and the breech projected backwards into the cockpit. In order to load and fire the gun, the unfortunate pilot had to be brought close up to the breech, and his position was thoroughly dangerous.
  The gun was heartily disliked by the R.N.A.S. pilots, and it was said that they refused to fire it when the W.B.V was flying. The Canon Puteaux was removed and replaced by a fixed Vickers machinegun and an upward-firing Lewis gun. With the removal of the quick-firing gun, however, the W.B.V apparently lost its raison d'etre for it was not developed further.


SPECIFICATION
  Manufacturers: William Beardmore & Co., Ltd., Dalmuir, Dumbartonshire.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: 35 ft 10 in. Length: 26 ft 7 in. Height: 11 ft 10 in. Chord: 6 ft 3 in. Gap: 4 ft 9 in. Span of tail: 11 ft 9 in. Airscrew diameter: 9 ft.
  Areas: Wings: 394 sq ft. Ailerons: each 18-8 sq ft, total 37-6 sq ft. Fin: 8 sq ft. Rudder: 12 sq ft.
  Weights: Empty: 1,860 lb. Military load: 160 lb. Pilot: 180 lb. Fuel and oil: 300 lb. Weight loaded: 2,500 lb.
  Performance: Maximum speed at ground level: 112 m.p.h.; at 10,000 ft: 103 m.p.h. Climb to 5,000 ft: 6 min;
to 10,000 ft: 17 min. Endurance: 2 1/2 hours.
  Tankage: Petrol: 37 gallons.
  Armament: Originally one 37 mm Puteaux quick-firing gun firing through the hollow airscrew shaft. This was replaced by one fixed, synchronised Vickers gun mounted centrally on top of the fuselage, and one Lewis gun firing upwards through an aperture in the centre-section.
  Production: Three W.B.Vs were ordered and at least two of them were built.
  Serial Numbers: N.41-N.43.

Blackburn Land/Sea Monoplane

  THIS little Blackburn monoplane did not appear in the form illustrated until 1915, but it could trace its ancestry back to a two-seat monoplane landplane which was built in 1913. The 1913 aircraft was sold to Dr M. G. Christie, who did a good deal of flying in it, and it was also flown by Harold Blackburn (who was no relation to Robert Blackburn, the founder of the Blackburn company). In the hands of Harold Blackburn the monoplane won the aerial “War of the Roses”, a 100-mile inter-county race held on October 2nd, 1913, for a silver challenge cup presented by the Yorkshire Evening News.
  A two-seater of similar design was used in 1914 for passenger flying, and may have been the Blackburn monoplane which was exhibited at the 1914 Olympia Aero Show. A seaplane version existed, originally powered by an 80 h.p. Gnome engine. Later a 100 h.p. Anzani radial was substituted, and in 1915 the aircraft was purchased by the Northern Aircraft Company. It was used by that concern as a seaplane trainer at Windermere, where it was flown extensively by W. Rowland Ding, and gave good service.
  The aircraft’s transformation into a seaplane had been achieved simply: a pair of pontoon-type floats had been attached to the skid structure of the undercarriage in place of the axle and wheels of the landplane. The floats and wheels were in fact regarded as interchangeable; hence the aircraft was known as the Land/Sea Monoplane.
  It was a simple aeroplane with a fabric-covered wooden structure. The fuselage had the triangular cross-section which had typified earlier Blackburn monoplanes, and there was a rounded top-decking. The mainplane was attached to the upper longerons, and was braced from above by wires from an inverted-vee cabane and from below by wires from the undercarriage. Lateral control was by wing-warping. The tail unit was wholly conventional, and incorporated a small tail float.
  

SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds, Yorkshire.
  Power: 100 h.p. Anzani.
  Dimensions: Span: 38 ft. Length: 28 ft 6 in.

Blackburn Seaplane Type L

  THE first biplane to be built by the Blackburn Company was a two-seat tractor floatplane which was designed to participate in the 1914 Daily Mail “Circuit of Britain” seaplane race. The machine was allotted the racing number 8, and was to have been flown by Sidney Pickles, but the outbreak of war prevented the contest from taking place. In common with several of its contemporaries the Blackburn machine, which was designated Type L, was taken over by the Admiralty. For war service it was, somewhat surprisingly, fitted with a machine-gun.
  The Type L was a handsome two-bay biplane with strut-braced extensions on the upper wing; ailerons were fitted to the upper wing only. The fuselage represented a breakaway from earlier Blackburn practice, for it was of rectangular cross-section, whereas all the monoplane antecedents of the Type L had had fuselages of triangular cross-section. The main longerons were of ash, and the fuselage structure embodied no wire cross-bracing: rigidity was obtained by the use of diagonal wooden members. The fuel tanks were mounted under the rounded top decking: in front of the pilot (who occupied the rear seat) was a tank containing 32 gallons of petrol, and in front of the passenger there was a divided tank which held five gallons of oil and sixteen of petrol.
  The machine was powered by a 130 h.p. Salmson water-cooled radial engine, the radiators for which were mounted outside the fuselage on either side of the front cockpit.
  The most noteworthy feature of the Type L lay in the design of its floats. Each float had two steps, the forward one of which was remarkably near the bow. The forward portion of each float had a vee bottom which gradually flattened out towards the second step, aft of which the bottom was flat but the lower line of the float was slightly concave in side elevation.
  The tail-unit was of typical Blackburn outline. The rudder was balanced, but the balance area was below the fuselage. All control cables were duplicated.
  It seems that the Type L did not see any real war service, despite its impressment by the Admiralty. It was taken to Scarborough and remained there for some six weeks; during that time it was apparently maintained by Blackburn mechanics. Early in 1915 it was taken up by Rowland Ding, the well-known pre-war pilot who became a Blackburn test pilot. During this flight it flew into a cliff and was wrecked.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: 130 h.p. Salmson radial engine.
  Dimensions: Span: upper 49 ft 6 in., lower 35 ft. Length: 32 ft 6 in. Chord: 5 ft 9 in. Gap: maximum 6 ft. Stagger: nil. Dihedral: upper nil, lower 2°. Incidence: 40. Span of tail: 11 ft 6 in. Distance between float centres: 8 ft 3 in.
  Areas: Wings: upper 294 1/2 sq ft, lower 186 1/2 sq ft, total 481 sq ft. Ailerons: each 21 sq ft, total 42 sq ft. Tailplane: 37-25 sq ft. Elevators: 24 sq ft. Fin: 5-75 sq ft. Rudder: 13-25 sq ft.
  Weights: Empty: 1,717 lb. Loaded: 2,475 lb.
  Performance: Maximum speed at sea level: 81 m.p.h.; at 10,000 ft: 64 m.p.h. Climb to 5,000 ft: 34 min. Ceiling: 11,000 ft. Endurance: 5 1/2 hours.
  Tankage: Petrol: 48 gallons. Oil: 5 gallons.
  Armament: One machine-gun, presumably a Lewis, fired by the passenger.

Blackburn T.B.

  THIS remarkable aeroplane was the Blackburn company’s first attempt to produce an aircraft designed for warlike purposes; it made its appearance in August, 1915. The T.B. was designed to fulfil Admiralty requirements for an anti-Zeppelin aircraft, and the specified armament was to consist of a load of steel darts. No doubt these missiles were Ranken Darts, an ingenious weapon which was designed to catch in the envelope of an airship and explode inside. The darts were usually carried in canisters of 24.
  Any justification for the adoption of the complicated twin-fuselage layout for the aircraft is hard to find: it may have been hoped to produce an aeroplane capable of lifting a heavy load of fuel to obtain a long flight endurance, in which case it might have been thought necessary to provide two pilots to minimise crew fatigue. However, the relatively low power of the engines which were fitted did not permit the lifting of heavy loads.
  Two prototypes were built. The first had two 100 h.p. Gnome Monosoupape rotary engines, and the second had two 110 h.p. Clergets. Blackburns were Admiralty contractors for the B.E.2C at the time of the construction of the T.B., and the two fins of the big twin were standard B.E.2C components, whilst the rudders were also of B.E. design but were slightly modified in outline.
  The structure was conventional throughout. The fuselages were wooden box-girders, cross-braced with wire and covered with fabric. Each fuselage had a main float at its forward end and a small tailfloat under its tail; the main floats were of the pontoon type and were not connected to one another. The long extensions of the upper wings were braced from above and below by cables. Ailerons were fitted to both upper and lower mainplanes: those on the upper wing were long and inversely tapered; the lower ailerons were very short.
  The performance of the Blackburn T.B. was quite creditable in view of its layout, but it could hardly have fared well in service. Difficulty of communication between the occupants of the two fuselages would have been a formidable handicap in action.
  The T.B. was tested at the R.N.A.S. Station, Isle of Grain, and the second machine, No. 1517, was there in 1916.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: First machine: two 100 h.p. Gnome Monosoupape. Second machine: two 110 h.p. Clerget.
  Dimensions: Span: upper 60 ft 6 in., lower 45 ft. Length: 36 ft 6 in. Chord: 5 ft 6 in. Gap: 6 ft 6 in. Stagger: nil. Dihedral: 40. Incidence: 40.
  Areas: Wings: upper 341 sq ft, lower 244 sq ft, total 585 sq ft. Ailerons: total 35-25 sq ft. Tailplane: 37 sq tt. Elevators: 27-25 sq ft. Fins: 15-25 sq ft. Rudders: 36 sq ft.
  Weights: Empty: 2,310 lb. Military load: 70 lb. Crew: 360 lb. Fuel and oil: 760 lb. Weight loaded: 3,500 lb.
  Performance (with Gnome engines): Maximum speed at sea level: 86 m.p.h. Climb to 5,000 ft: 12 min. Endurance: 4 hours.
  Armament: 70 lb of steel darts.
  Serial Numbers: 1510 and 1517.

Blackburn G.P. and S.P.

  THE Blackburn G.P. appeared in 1916. It was a large twin-engined biplane with a twin-float undercarriage, and was designed as a three-seat patrol bomber. It was one of the earliest aircraft designed to carry a torpedo. The upper wings had long wire-braced extensions, and bore the ailerons; there were no control surfaces on the lower wings. The G.P. was powered by two 225 h.p. Sunbeam engines which drove opposite-handed four-bladed airscrews. The radiators were mounted vertically on each rear interplane strut flanking the engine nacelles.
  The wings could be folded to facilitate stowage. This structural feature was not unique in 1916, but was still regarded as unusual, particularly in such a large machine.
  The second aircraft to be built to the same basic design as the G.P. embodied a greater proportion of metal components, and was powered by two 250 h.p. Rolls-Royce Falcon engines. This version was designated Blackburn S.P., and externally had little to distinguish it from the G.P. The engines again drove four-bladed airscrews, but the exhaust pipes ran along the sides of the nacelles instead of above, as in the case of the Sunbeam engines which had their exhaust valves on the inboard sides of the cylinders.
  The principal difference between the S.P. and the G.P. lay in the greatly increased aileron area of the S.P. Ailerons were fitted to the lower mainplanes: they extended from the second pair of interplane struts out to the wing-tips, and the ailerons on the upper wing were lengthened correspondingly. Upper and lower ailerons were connected by a faired steel tube, and it seems probable that they may have been arranged to droop together and thus act as air-brakes, in the manner of the later Kangaroo. The trailing edges of the S.P.’s rudders were made of wire; consequently they were “feathered”, whereas the more substantial trailing edges of the rudders of the G.P. were quite straight.
  The type did not go into production, but a landplane conversion named the Kangaroo was built in some numbers. The tests of the G.P. were carried out at the Isle of Grain, and the S.P. was tested at Brough.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: G.P.: two 225 h.p. Sunbeam. S.P.: two 250 h.p. Rolls-Royce Falcon.
  Dimensions: Span: upper 74 ft 10 1/4 in., lower 52 ft 10 1/2 in. Length: 46 ft. Height: 16 ft 10 in. Chord: 7 ft 3 in. Gap: 7 ft 3 in. Stagger: nil. Dihedral: 5. Incidence: 5. Span of tail: 17 ft 6 in.
  Areas: Wings: upper 536 sq ft, lower 344 sq ft, total 880 sq ft. Ailerons: total 166-5 sq ft (on S.P.). Tailplanes: 80 sq ft. Elevators: 63-5 sq ft. Fins: 25 sq ft. Rudders: 22-5 sq ft.
  Weights: (S.P.) Empty: 5,840 lb. Military load: 1,170 lb. Crew: 540 lb. Fuel and oil: 1,050 lb. Weight loaded: 8,600 lb.
  Performance: (S.P.) Maximum speed at sea level: 97 m.p.h.; at 10,000 ft: 77 m.p.h. Climb to 5,000 ft: 10 min; to 10,000 ft: 30 min. Ceiling: 11,000 ft. Endurance: 8 hours.
  Tankage: Petrol: 230 gallons. Oil: 18 gallons.
  Armament: Two free Lewis machine-guns on Scarff ring-mountings, one on the nose cockpit, the other on the rear cockpit aft of the wings. Four 230-lb bombs or one torpedo.
  Serial Numbers: 1415 (G.P.) and 1416 (S.P.).

Blackburn Triplane

  WORK on the design of the Blackburn Triplane began at the end of 1915. It was a single-seat fighter which was intended to achieve the same object as the contemporary D.H.a; namely, to provide a fighting aircraft with armament which could be fired straight ahead.
  The Blackburn Triplane obviously owed a good deal to the A.D. Sparrow, for which the Blackburn company had been contractors, and it is probable that Harris Booth had a hand in the design of the triplane. There was the same enormous gap between upper and lower tail-booms; a long-span tailplane was fitted; there were two large, widely-spaced fins and rudders; and in appearance the nacelle was as uncouth as that of the Sparrow. On the triplane, ailerons were fitted to all wings; only the central ailerons were connected directly to the pilot’s control column, and the top and bottom surfaces were actuated by connecting struts. The tail-booms were parallel in both plan and side elevation, and the entire tail assembly appeared to be of doubtful rigidity. The machine was flown with both the 100 h.p. Gnome Monosoupape and the 110 h.p. Clerget engines: in the latter case a four-bladed airscrew was used.
  The only available performance figures credit the Triplane with a maximum speed of 115 m.p.h. with the Monosoupape engine, but this claim must be regarded as somewhat optimistic; for the D.H.2 could reach only 93 m.p.h. with the same engine.
  It has been said that two Blackburn Triplanes were built, one of which was tested at York and the second sent to Eastchurch. However, it seems unlikely that two machines existed; it is more probable that a confusion with the A.D. Sparrow arose.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: 100 h.p. Gnome Monosoupape; 110 h.p. Clerget.
  Dimensions: Span: 24 ft. Length: 21 ft 5 5/16 in. Chord: 3 ft 5 in. Gap: 3 ft 6 in. Stagger: 9 in. Dihedral: nil. Incidence: 2°. Span of tail: 18 ft. Wheel track: 5 ft. Airscrew diameter: 8 ft.
  Areas: Wings: top 79-108 sq ft, middle 67-116 sq ft, bottom 74-806 sq ft, total 221-03 sq ft. Ailerons: each 6-53 sq ft, total 39-2 sq ft. Tailplane: 29-7 sq ft. Elevators: 25-1 sq ft. Fins: 15-2 sq ft. Rudders: 23-9 sq ft.
  Weights: Empty: 1,011 lb. Military load: 50 lb. Pilot: 180 lb. Fuel and oil: 259 lb. Weight loaded: 1,500 lb.
  Performance (with Monosoupape engine): Maximum speed: 115 m.p.h. Endurance: 3 hours.
  Armament: One free-mounted forward-firing Lewis machine-gun in front of pilot.
  Serial Number: N.502, built under Contract No. C.P. 120730/16.

Blackburn Kangaroo

  THE Kangaroo was a landplane development of the G.P. and S.P. seaplane design, and was intended for Service use as a bomber. In general appearance it was virtually identical to the earlier floatplanes, apart from the substitution of the wheel undercarriage. The Kangaroo’s rudders were of slightly greater area, and the kingpost structures above the upper wing were rectangular; those of the floatplanes had been triangular.
  The undercarriage had four wheels arranged in two pairs; each pair of wheels was mounted on two vee-struts directly under each engine. The original undercarriage was noteworthy for the complete absence of shock absorbers, but later the front leg of each vee incorporated an oleo strut.
  Development of the Kangaroo seems to have proceeded rather slowly. The trials during which the appended performance figures were obtained were conducted in January, 1918. The Kangaroo which was used was B.9970, which at that time still had the rigid undercarriage.
  The official report on the type was not particularly complimentary. The small cross-section of the fuselage was adversely criticised, both structurally and from the standpoint of crew comfort and function. When coming out of a steeply-banked turn, the fuselage would twist aft of the rearmost cockpit, indicating a lack of torsional rigidity; and it was too shallow to allow the gunners to make effective use of their guns. The Kangaroo was said to be quite pleasant to fly, but was markedly nose heavy with power off, and the rudders were described as “difficult to operate”; rudder pedals were fitted in place of the more common rudder bar. The ailerons on both upper and lower wings were arranged to droop to act as air brakes; and the wings could be folded.
  Limited production of the Kangaroo was undertaken, but only eleven machines had been delivered by the time of the Armistice. The Kangaroo’s active service was chiefly given as the equipment of an anti-submarine squadron at Seaton Carew, near the mouth of the River Tees, but the machine is also said to have been used for a short time by a bomber squadron in Belgium in 1918. It was reported that the Kangaroo bombers suffered badly from enemy bombing of their aerodrome.
  The machines of the Seaton Carew squadron flew 600 hours on anti-submarine patrols between May 1 st, 1918, and the date of the Armistice. During that time the Kangaroos sighted twelve U-boats and attacked eleven of them.
Kangaroo B.9983 from Seaton Carew was instrumental in bringing about the destruction of the enemy submarine U.C.70 on August 28th, 1918. The machine was flown by Lieutenant E. F. Waring with Lieutenant H. J. Smith as his observer, and they sighted the submarine at 3.25 p.m., apparently lying on the sea-bed near Runswick Bay. Waring dropped a 520-lb bomb, which exploded 30 feet from the bows of the submarine, and the destroyer H.M.S. Ouse came up to drop depth charges, the last of which exploded directly on top of the U-boat’s hull.
  After the war the surviving Kangaroos returned to the Blackburn company at Brough, and many were converted for commercial use in one way or another. Three were acquired by the Grahame-White Aviation Company for joy-riding at Hendon, and four were operated by the North Sea Aerial Navigation Co., Ltd., an offshoot of the Blackburn concern.
  In an attempt to win the Australian Government’s prize of £10,000 for the first England-Australia flight by a Commonwealth airman, the Kangaroo G-EAOW left Hounslow on November 21st, 1919, bound for Australia - nine days after the departure of Ross and Keith Smith in their Vickers Vimy. This Kangaroo was powered by two specially tuned Rolls-Royce Falcon Ills fitted with special carburettors and 12-point magnetos. The crew of the Kangaroo were Lieutenants Vai Rendle and D. R. Williams, Captain G. H. Wilkins, M.C., and Lieutenant G. H. Potts. Unfortunately the flight had to be abandoned on December 8th after a forced landing made at Canea, Crete.
  The last Kangaroos were those which were used as trainers until 1929 by the renamed North Sea Aerial and General Transport Co., Ltd. The aircraft were used to provide twin-engine training at the R.A.F. Reserve School, Brough.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds. Power: Two 250 h.p. Rolls-Royce Falcon.
  Dimensions: Span: upper 74 ft 10 1/4 in., lower 52 ft 10 1/2 in. Length: 46 ft. Height: 16 ft 10 in. Chord: 7 ft 3 in. Gap: 7 ft 3 in. Stagger: nil. Dihedral: 5. Incidence: 5. Span of tail: 17 ft 6 in. Track of each undercarriage unit: 5 ft. Tyres: 900 X 200 mm. Airscrew diameter: 9 ft 10 in.
  Areas: Wings: upper 536 sq ft, lower 344 sq ft, total 880 sq ft. Total aileron area: 166-5 sq ft. Tailplanes: 80 sq ft. Elevators: 63-5 sq ft. Fins: 25 sq ft. Rudders: 22-5 sq ft.
  Weights and Performance: No. of Trial Report: M.169. Date of Trial Report: January, 1918. Type of airscrew used on trial: S.D.440. Weight empty: 5,284 lb. Military load: 463 lb. Crew: 540 lb. Fuel and oil: 1,730 lb. Loaded: 8,017 lb. Maximum speed at ground level: 100 m.p.h.; at 6,500 ft: 98 m.p.h.; at 10,000 ft: 86 m.p.h. Climb to 1,000 ft: 2 min; to 2,000 ft: 4 min 10 sec; to 5,000 ft: 12 min 30 sec; to 6,500 ft: 18 min 10 sec; to 8,000 ft: 25 min 05 sec; to 10,000 ft: 38 min 10 sec; to 10,600 ft: 44 min. Service ceiling: 10,500 ft. Endurance: 8 hours.
  Tankage: Petrol: front pressure tank 97 1/2 gallons; rear pressure tank 118 gallons; total 215 1/2 gallons. Oil: two tanks, one on inside of each engine, 16 gallons. Water: 7 1/4 gallons.
  Armament: One Lewis machine-gun on Scarff ring-mounting on nose cockpit; another Lewis gun was similarly installed on the rear cockpit. The original conception of the machine envisaged an underslung position for a prone lower rear gunner, accommodated in a “bath” structure below the rear cockpit; this idea was abandoned. Four 230-lb bombs could be carried internally, suspended by their noses, and there were external racks for four bombs under the fuselage.
  Service Use: Used by an anti-submarine squadron (probably No. 246) at Seaton Carew. A few may have been used with a bomber unit based in Belgium.
  Production and Allocation: Eleven Kangaroos were delivered to the R.A.F. in 1918, but at least fifteen had been built by October 31st, 1918. On that date, ten were with the Seaton Carew squadron, one was at a training unit, and three were at Aircraft Acceptance Parks; one machine was written off during October.
  Serial Numbers: B.8837-B.8840; B.9970-B.9989 (originally ordered as N.1720-N.1739) built under Contract No. A.S.7469.
  Costs:
   Airframe without engines, instruments or armament £5,648
   Rolls-Royce Falcon engine (each) £1,210

Blackburn Blackburd

  BY the end of 1917, the idea of using torpedo-carrying landplanes operating from aircraft-carriers had been accepted, and the Sopwith Cuckoo was in production. The Cuckoo’s warload consisted of a Mark IX eighteen-inch torpedo which contained 170 lb of T.N.T., but official opinion at the end of 1917 was that the Mk. IX torpedo was not sufficiently powerful to be effective against battleships.
  It was therefore requested that an aeroplane be provided which would be capable of carrying the Mk. VIII torpedo, containing 320 lb of T.N.T. A specification was issued and orders for three prototypes each were given to the Blackburn company and to Short Brothers. The resulting aircraft were the Blackburd and the Shirl respectively.
  The Blackburd was not the first Blackburn type to carry a torpedo, for both the G.P. and the Kangaroo had been capable of doing so; but it was the first Blackburn aeroplane to be specifically designed for that purpose.
  The Blackburd was obviously designed for ease and rapidity of production, and its box-like fuselage of constant depth was evidence enough that the smallest pretence of elegance had been ruthlessly suppressed in the attainment of utility. Since the machine was intended for shipboard use the design incorporated folding wings, the aeroplane’s most remarkable feature lay in its undercarriage, however.
  At the time the Blackburd appeared, deck landing was still in its infancy. Much experimental work had been carried out at the Marine Experimental Aircraft Depot, Isle of Grain, with Sopwith Pups and 1 1/2-Strutters, fitted with wheel-less skid undercarriages. It was recognised that some form of arrester gear was necessary, but none had been standardised by the time of the Armistice.
  The Blackburd’s undercarriage sought to have the best of two worlds by providing wheels for take-off and steel skids for landing. In view of the machine’s designed function, it is remarkable that the two wheels were connected by a rigid transverse axle. The wheels and axle had to be jettisoned before the torpedo could be dropped, and the landing was made on the skid portion of the undercarriage which remained. Shock absorption was provided by two oleo struts, one on each side.
  A further argument advanced in support of the arrangement was that the absence of wheels would minimise the danger of nosing over if the Blackburd were forced to alight on the water. Inflatable air bags were fitted inside the fuselage to serve as emergency flotation gear.
  The test flights and first skid landings were carried out by R. W. Kenworthy. The skids underwent various modifications before they were pronounced satisfactory. By that time the war was over and the need for the Blackburd had passed. On test, the machine proved to be somewhat inferior to the Sopwith Cuckoo, for it was slower and lacked the manoeuvrability required during close-range attacks.
  The second Blackburd, N.114, differed from the first in having small floats attached to the underside of the lower wings in similar fashion to the Beardmore W.B.IV. It also had a larger, squarer radiator and a deeper nose.

SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: 350 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: upper 52 ft, lower 52 ft 6 in. Length: 36 ft 3 in. Height: 12 ft 4 1/2 in. Chord: 7 ft. Gap: 7 ft. Stagger: -1°. Dihedral: 2° 03'. Incidence: 0° 45'. Span of tail: 17 ft.

Weights (lb) and Performance:
Without Torpedo With Torpedo
No. of Trial Report M.208 M.208
Date of Trial Report June, 1918 June, 1918
Type of airscrew used on trial A.B.8520 A.B.8580
Weight empty 3,228 3,228
Military load - 1,671
Pilot 180 180
Fuel and oil 512 621
Weight loaded 3,920 5,700
Maximum speed (m.p.h.) at
ground level - 92
6,500 ft 95 90-5
10,000 ft 94-5 84-5
15,000 ft 89-5
m. s. m. s.
Climb to
6,500 ft 8 40 16 10
10,000 ft 15 05 33 25
15,000 ft 28 40 - -
Service ceiling (feet) 19,000 11,000
Endurance (hours) - 3

  Areas: Wings: upper 345-5 sq ft, lower 349-5 sq ft, total 695 sq ft. Total aileron area: 77-5 sq ft. Tailplane: 61 sq ft. Elevators: 27 sq ft. Fin: 19-5 sq ft. Rudder: 9 sq ft.
  Tankage: Petrol: 69 gallons. Oil: 9 gallons.
  Armament: One Mark VIII torpedo of 1,400 lb in crutches below the fuselage.
  Serial Numbers: N. 113-N. 115.

Blackburn N.1B

  CONSTRUCTION of the Blackburn N.1B began in 1917. It was designed as a single-seat fighter flying boat, and was intended to be used as an escort to the big patrol flying boats. Not unnaturally, the machine was known as the “Nib” in the Blackburn works: its true designation N.1B derived from the number of the Admiralty category to which it was appropriate.
  The hull was of Linton Hope design, and its structure was the typical framework of circular wooden hoops and stringers, planked diagonally with strips of mahogany. There were two steps, and the top line of the hull swept upwards slightly to the biplane tail unit. As on the A.D. Flying Boats, the upper tailplane had reversed camber. Both mainplanes and tailplanes were designed to have elliptical tips, and the mainplanes were arranged to fold. The 200 h.p. Hispano-Suiza engine was installed as a pusher under the upper centre-section.
  Unfortunately, Service requirements changed while the N.1B was building, and only the hull was completed by the time of the Armistice. This hull was still in excellent condition in 1923, when the Blackburn company decided to enter a machine in the Schneider Trophy contest. It was therefore fitted with biplane wings of sesquiplane configuration and a single-rudder monoplane tail unit. A 450 h.p. Napier Lion engine was installed above the upper wing, and drove a tractor airscrew which revolved in perilous proximity to the pilot’s head.
  In this form the machine was named the Blackburn Pellet and was registered G-EBHF. It was to be flown by R. W. Kenworthy in the Schneider Trophy contest at Cowes. When first launched for trials in the Humber the Pellet went down on her starboard wing, turned over slowly, and threw Kenworthy into the river. Salvage, repair and modifications to the wing-tip floats left time for only one test flight on the eve of the race, and during that flight Kenworthy found that the Pellet was nose-heavy. There was no time to correct this fault, but larger Lamblin radiators were installed by all-night work on the part of the Blackburn mechanics: the original radiator was inadequate, and Kenworthy had been forced to alight hurriedly with the water boiling.
  The Pellet’s next and last flight was begun as part of the navigability trials which were included in the contest. The machine became airborne at 140 knots, but immediately porpoised badly, turned turtle and sank. Miraculously, Kenworthy survived unhurt.


SPECIFICATION
  Manufacturers: The Blackburn Aeroplane & Motor Co., Ltd., Olympia, Leeds.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: upper 34 ft 10 in., lower 29 ft 4 in. Length: 28 ft 3 1/2 in. Chord: 5 ft 6 in. Gap: 6 ft 9 in. Stagger: 3. Dihedral: 3. Incidence: 3.
  Areas: Wings: upper 170 sq ft, lower 144 sq ft, total 314 sq ft. Ailerons: each 41-5 sq ft, total 83 sq ft. Tailplanes: 30-25 sq ft. Elevators: 21-5 sq ft. Fins: 11 sq ft. Rudders: 9 sq ft.
  Weights: Empty: 1,721 lb. Loaded: 2,390 lb.
  Performance (Estimated): Maximum speed at sea level: 114 m.p.h.; at 10,000 ft: 108 m.p.h. Climb to 5,000 ft: 7 min; to 10,000 ft: 18 min. Ceiling: 16,000 ft. Endurance: 3 hours.
  Armament: One forward-firing Lewis machine-gun mounted above the hull in front of the cockpit, to starboard of centre.
  Serial Numbers: N.56-N.58.

Boulton & Paul P.3, the Bobolink

  IN common with many other firms which normally engaged in wood-working of one kind or another, Messrs Boulton & Paul, Ltd., of Norwich, undertook the construction of aircraft during the 1914-18 war. From the manufacture of wooden buildings the firm turned to the production of such aeroplanes as the F.E.ad, Sopwith 1 1/2-Strutter and Sopwith Camel. Under the energetic management of Geoffrey Ffiske the firm developed its aircraft side with J. D. North as chief designer. It is not surprising therefore that a Boulton & Paul design appeared in 1918.
  This first Boulton & Paul aeroplane was a single-seat fighter biplane, designated P.3 and at first named “Hawk” by its manufacturers. It was later officially named Bobolink, however. It was the company’s entry in the design competition for a single-seat fighter with the 230 h.p. Bentley B.R.2 engine to replace the Sopwith Camel. The competition was ultimately won by the Sopwith Snipe, however, and the Bobolink did not go into production. The Bobolink’s all-round performance was rather better than that of the Snipe, and its flying characteristics were good. Unfortunately, the comparatively narrow track of the undercarriage made the Bobolink somewhat difficult to handle on the ground, and this fact was to some extent responsible for the machine’s lack of success.
  A less understandable official reason for the non-acceptance of the Bobolink was that the Snipe was considered to be a slightly simpler aircraft and more suitable for production in quantities. How this view could be justified is not immediately clear, particularly if the Snipe’s rounded fuselage with its complications of formers and stringers is compared with the plain wire-braced box girder structure of the Bobolink. An unusual structural feature of the Bobolink was the use of N-type interplane struts, but that should have simplified rigging and could not, in fairness, be regarded as a drawback. The wings were remarkably light: each lower mainplane weighed only 29 lb before covering.
  In general, detail design closely followed Sopwith practice, and all fittings required a minimum of machining.
  The fuel supply was carried in two main tanks located immediately behind the pilot’s seat and separated by a sheet of armour plate: this, it was hoped, would minimise the risk of any one bullet damaging both tanks. The main fuel tanks could be jettisoned in flight, in order to avoid complete destruction of the aeroplane in the event of the petrol being set on fire.


SPECIFICATION
  Manufacturers: Boulton & Paul, Ltd., Riverside, Norwich.
  Power: 230 h.p. Bentley B.R.2, engine No. E.X.4.
  Dimensions: Span: 29 ft. Length: 20 ft. Height: 8 ft 4 in. Chord: upper 5 ft 4 1/2 in., lower 4 ft in. Gap: 3 ft 10 5/8 in. Stagger: 2 ft 3 1/2 in. Dihedral: 2° 30'. Incidence: 0°. Span of tail: 9 ft 2 in. Airscrew diameter: 9 ft.
  Areas: Wings: 266 sq ft. Ailerons: each 7.5 sq ft, total 15 sq ft. Tailplane: 20 sq ft. Elevators: 10 sq ft. Fin: 2 sq ft. Rudder: 10 sq ft.
  Weights and Performance: No. of Trial Report: M.188. Date of Trial Report: March, 1918. Type of airscrew used on trial: Lang 4040.
  Weights: Empty: 1,226 lb. Military load: 228 lb. Pilot: 180 lb. Fuel and oil: 358 lb. Weight loaded:, 1,992 lb.
  Performance: Maximum speed at 10,000 ft: 125 m.p.h.; at 15,000 ft: 109 m.p.h. Climb to 6,500 ft: 5 min 20 sec; to 10,000 ft: 9 min 20 sec; to 15,000 ft: 18 min. Service ceiling: 19,500 ft. Endurance: 3 1/4 hours at 15,000 ft.
  Tankage: Petrol: main tank 34 gallons, auxiliary tank 6 gallons; total 40 gallons.
  Armament: Two Vickers machine-guns mounted on top of the fuselage and synchronised to fire forward through the revolving airscrew. The original design included a semi-free Lewis gun above the centre-section.
  Serial Numbers: C.8652-C.8657: ordered under Contract No. A.S.37485.

Boulton & Paul P.7, the Bourges

  THE manoeuvrability of the Boulton & Paul Bourges, especially when demonstrated by Captain F. T. Courtney, is now almost legendary; and indeed its tractability was remarkable for its day, when all twin-engined aeroplanes were regarded as elephantine and unlikely to commit any indiscretion such as a loop.
  The Bourges was a sturdy, well-proportioned biplane intended for service as a fighter-bomber. Design work began in 1918 and three prototypes were ordered. The official designations of the several versions of the Bourges differ from those which have gained a certain currency; the official Mark numbers are as quoted below.
  The Bourges was designed originally to have two 320 h.p. A.B.C. Dragonfly engines. This version was officially named Bourges Mark I, and the suffix letter A was to be added to indicate a conventional straight-through upper centre-section, whilst suffix B was to indicate a dropped or gull-wing centresection.
  However, the first Bourges airframe, F.2903, was ready before engines were available. It was desired to carry out test flights as quickly as possible, so the machine was fitted with two 230 h.p. Bentley B.R.2 rotary engines in order to enable it to be flown. Plain ailerons were fitted. This version was officially designated Bourges Mk. II - or, more fully, Mk. IIA, for it had a straight-through centre-section. This designation is exactly analogous to the designations of the B.A.T. Bantam II, Avro Manchester Mk. II and Sopwith Cobham Mk. II.
  When Dragonfly engines became available they were installed in F.2903. At first they had very clean nacelles with large blunt spinners on the airscrews, but these did not prove satisfactory, aerodynamically or structurally. The spinners were removed and modified engine cowlings were fitted. In this form the Bourges had horn-balanced ailerons, and ultimately the rudder area was slightly increased. The official designation of this version was Bourges Mk. IA.
  It is in this form that the Bourges is best remembered. For a twin-engined aeroplane its manoeuvrability was phenomenal, thanks to its relatively short wing span and low wing loading: it could be looped, rolled and spun almost as easily as contemporary fighters.
  The second Bourges, F.2904, was officially designated Mark IB (though it has been popularly better known as the Mk. IA), and differed considerably from the true Mk. IA. With the object of improving the rear gunner’s field of fire, the upper mainplane was made as a gull wing: from the struts above the engines the wing sloped downwards to meet the top of the fuselage. Equally unusual was the sharp dihedral angle on the tailplane; each half was parallel to the inclined portions of the upper mainplane. The Dragonfly engines were mounted directly on to the lower mainplane and the enlarged rudder was fitted. The fin area was reduced slightly, and the vertical tail surfaces were therefore more nearly circular in outline.
  Under the designation Bourges Mk. Ill a further version was projected with two Siddeley Puma engines, most probably of the ago h.p. high-compression type which was used as an alternative to the A.B.C. Dragonfly in the contemporary Avro Manchester and Sopwith Cobham. This version was never built, but the third Bourges airframe, F.2905, was completed and flown with two Napier Lion engines of 450 h.p. each. The engines were mounted on the lower wings, and additional sloping struts were added to the centre-section bracing. The Lion-powered Bourges had the same fin and rudder as the Mk. IB. It has usually been known as the Bourges Mk. II, but that official designation had already been used for the version with B.R.2 engines.


SPECIFICATION
  Manufacturers: Boulton & Paul, Ltd., Riverside, Norwich.
  Power: Bourges Mk. I: two 320 h.p. A.B.C. Dragonfly I. Bourges Mk. II: two 230 h.p. Bentley B.R.2. Bourges Mk. Ill: projected installation of two 290 h.p. Siddeley Puma. The third airframe was fitted with two 450 h.p. Napier Lion.
  Dimensions: Span: 54 ft with plain ailerons, 57 ft 4 in. with horn-balanced ailerons. Length: 37 ft. Height: 12 ft. Chord: upper 8 ft, lower 6 ft 6 in. Gap: 6 ft 6 in. Span of tail: 16 ft. Airscrew diameter (Dragonfly): 9 ft 6in.
  Areas: Wings: 738 sq ft. Ailerons: each 27 sq ft, total 108 sq ft. Tailplane and elevators: 96 sq ft. Fin: 14 sq ft. Rudder: 21 sq ft.
  Weights and Performance (Dragonfly Engines) : No. of Trial Report: M.262. Date of Trial Report: August, 1919. Type of airscrew used on trial: A.B.8973. Weight empty: 3,820 lb. Military load: 436 lb. Crew: 540 lb. Fuel and oil: 1,530 lb. Loaded:6,326 lb. Maximum speed at 6,500 ft: 123-5 m.p.h.; at 10,000 ft: 121 m.p.h.; at 15,000 ft: 112-5 m.p.h. Climb to 6,500 ft: 7 min 40 sec; to 10,000 ft: 13 min 35 sec; to 15,000 ft: 25 min 25 sec. Service ceiling: 20,000 ft. Endurance: 9 1/4 hours. With Napier Lion Engines: Weight loaded: 6,800 lb. Maximum speed at 10,000 ft: 130 m.p.h.
  Tankage: Petrol: 1 go gallons.
  Armament: One Lewis machine-gun on Scarff ring-mounting on nose cockpit; one Lewis gun on Scarff ring-mounting on cockpit aft of wings. Bomb load.
  Production: Three prototypes were built.
  Serial Numbers: F.2903-F.2905.

Bristol Box-kite

  THE greater part of the Bristol Box-kite’s history falls within the period before the outbreak of the 1914-18 war, yet the last contract for the type was placed by the Admiralty as late as September 26th, 1914, and one was still flying at the Australian Flying Corps School at Point Cook in October, 1915. The machine served during the war period, and therefore deserves a place in this history; but an equally strong claim for the inclusion of the Box-kite could be based on the fact that, of the four serviceable aeroplanes possessed by the R.F.C. on its formation in May, 1912, two were Bristol Box-kites.
  The first true Bristol Box-kite appeared in June, 1910, and bore the British & Colonial Aeroplane Company’s works number 7. It was designed by G. H. Challenger after the company’s licence-built Zodiac biplane proved to be a failure. This machine began life with a 50 h.p. Gregoire engine, but was later converted to take the 50 h.p. Gnome rotary for use at the Bristol company’s flying school at Brooklands. The type owed a good deal to contemporary Farman designs. It was a typical primitive biplane with forward elevator and exposed pilot. Some later machines had a rudimentary nacelle, but all were characterized by the inevitable maze of bracing wires.
  Two Bristol Box-kites participated in the Army manoeuvres of September, 1910, with great success. They were flown by Robert Loraine and Captain Bertram Dickson. Loraine’s machine had a 50 h.p. E.N.V. engine, and had a primitive wireless transmitting set on board, from which messages were transmitted while the Box-kite was airborne. These messages were received at a range of up to one mile. Captain Dickson’s Box-kite, which was Bristol No. 9, was specially modified for weight-carrying. Detachable extensions were fitted to the upper mainplanes, and the fuel tanks were larger than those of earlier models.
  Considerable numbers of Box-kites were made, normally with the 50 h.p. Gnome, but other types of engine were fitted. From the modified Box-kite built for Captain Dickson was developed the Military type, strengthened and with a third central rudder in the tail unit. The Military type was the subject of the first contract placed by any government for a quantity of aeroplanes: eight machines, powered by the 70 h.p. Gnome, were supplied to the Russian Government in February, 1911. Two months later the first Military Box-kite for the British Army Air Battalion was delivered, followed later by five further complete machines and two spare “fuselage” structures. Two of these Box-kites had 60 h.p. Renault engines.
  The first Box-kite to have the small nacelle for pilot and passenger was Bristol No. 31, which was exhibited at the 1911 Aero Show at Olympia. A similar machine Was shown at the Russian Aeronautical Exhibition held at St Petersburg at the end of April, 1911; it was bought by the Russians as an addition to the eight already on order. When delivered, all the Russian machines had small nacelles. They were tested in England by Captain Dimitri Alexandrov of the Russian Army. The Box-kite proved to be eminently suitable for elementary flying training, and was used at the Bristol company’s flying schools at Larkhill and Brooklands, where many men who were later to win distinction in the field of aviation “took their tickets” on the type. Various examples went to India, Spain, Singapore, Pretoria, Bulgaria, Australia and Germany. One of the machines sent to Germany was a sample for the Deutsche Bristol-Werke: this concern, after the inevitable severing from its parent firm upon the outbreak of war, produced the well-known Halberstadt designs which provided later Bristol products with targets.
  The six Box-kites ordered by the Admiralty in September, 1914, went to R.N.A.S. flying schools at Hendon and Eastchurch, and survived until about May of the following year. The longest-lived Box-kite was Bristol No. 133, which went to Australia in January, 1913, and was still flying there in October, 1915.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: Standard: 50 h.p. Gnome. The eight machines built for Russia had the 70 h.p. Gnome, as had the three improved Military Box-kites, which also had the small nacelle. Other engines fitted were the 50 h.p. Gregoire, 50 h.p. E.N.V. and the 60 h.p. Renault.
  Dimensions: Span: 33 ft (46 ft 6 in. with extensions). Length: 38 ft 6 in. Height: 11 ft. Chord: 6 ft 7 in. Gap: 6 ft 8 in. Stagger: nil. Dihedral: nil. Span of tail: 8 ft. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: 457 sq ft (517 sq ft with extensions). Tailplanes: 89 sq ft. Rear elevator: 22-5 sq ft. Forward elevator: 30-5 sq ft. Rudders: 26-5 sq ft.
  Weights: Loaded: 900 lb.
  Performance: Maximum speed: 40 m.p.h.
  Tankage (Military Type): Petrol: 19 gallons. Oil: 9 gallons.
  Service Use: No. 2 (Aeroplane) Company, Air Battalion, Royal Engineers, later No. 3 Squadron, R.F.C. R.N.A.S. flying schools at Eastchurch, Hendon and Eastbourne. Also used at Bristol flying schools at Larkhill and Brooklands, and by Eastbourne Aviation Co.
  Production: Standard Box-kite: 16. Extended Box-kite: 5. Military Box-kite: 40. Military Box-kite trainer (60 h.p. Renault): 2. Military Box-kite, 70 h.p. Gnome (for Russia): 9. Improved Military Box-kite (with nacelle): 4. Total production: 76.
  Serial Numbers: 12, 24, 942-947 (built under Contract No. C.P.56037/14/x.)

Bristol Box-kite

  THE greater part of the Bristol Box-kite’s history falls within the period before the outbreak of the 1914-18 war, yet the last contract for the type was placed by the Admiralty as late as September 26th, 1914, and one was still flying at the Australian Flying Corps School at Point Cook in October, 1915. The machine served during the war period, and therefore deserves a place in this history; but an equally strong claim for the inclusion of the Box-kite could be based on the fact that, of the four serviceable aeroplanes possessed by the R.F.C. on its formation in May, 1912, two were Bristol Box-kites.
  The first true Bristol Box-kite appeared in June, 1910, and bore the British & Colonial Aeroplane Company’s works number 7. It was designed by G. H. Challenger after the company’s licence-built Zodiac biplane proved to be a failure. This machine began life with a 50 h.p. Gregoire engine, but was later converted to take the 50 h.p. Gnome rotary for use at the Bristol company’s flying school at Brooklands. The type owed a good deal to contemporary Farman designs. It was a typical primitive biplane with forward elevator and exposed pilot. Some later machines had a rudimentary nacelle, but all were characterized by the inevitable maze of bracing wires.
  Two Bristol Box-kites participated in the Army manoeuvres of September, 1910, with great success. They were flown by Robert Loraine and Captain Bertram Dickson. Loraine’s machine had a 50 h.p. E.N.V. engine, and had a primitive wireless transmitting set on board, from which messages were transmitted while the Box-kite was airborne. These messages were received at a range of up to one mile. Captain Dickson’s Box-kite, which was Bristol No. 9, was specially modified for weight-carrying. Detachable extensions were fitted to the upper mainplanes, and the fuel tanks were larger than those of earlier models.
  Considerable numbers of Box-kites were made, normally with the 50 h.p. Gnome, but other types of engine were fitted. From the modified Box-kite built for Captain Dickson was developed the Military type, strengthened and with a third central rudder in the tail unit. The Military type was the subject of the first contract placed by any government for a quantity of aeroplanes: eight machines, powered by the 70 h.p. Gnome, were supplied to the Russian Government in February, 1911. Two months later the first Military Box-kite for the British Army Air Battalion was delivered, followed later by five further complete machines and two spare “fuselage” structures. Two of these Box-kites had 60 h.p. Renault engines.
  The first Box-kite to have the small nacelle for pilot and passenger was Bristol No. 31, which was exhibited at the 1911 Aero Show at Olympia. A similar machine Was shown at the Russian Aeronautical Exhibition held at St Petersburg at the end of April, 1911; it was bought by the Russians as an addition to the eight already on order. When delivered, all the Russian machines had small nacelles. They were tested in England by Captain Dimitri Alexandrov of the Russian Army. The Box-kite proved to be eminently suitable for elementary flying training, and was used at the Bristol company’s flying schools at Larkhill and Brooklands, where many men who were later to win distinction in the field of aviation “took their tickets” on the type. Various examples went to India, Spain, Singapore, Pretoria, Bulgaria, Australia and Germany. One of the machines sent to Germany was a sample for the Deutsche Bristol-Werke: this concern, after the inevitable severing from its parent firm upon the outbreak of war, produced the well-known Halberstadt designs which provided later Bristol products with targets.
  The six Box-kites ordered by the Admiralty in September, 1914, went to R.N.A.S. flying schools at Hendon and Eastchurch, and survived until about May of the following year. The longest-lived Box-kite was Bristol No. 133, which went to Australia in January, 1913, and was still flying there in October, 1915.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: Standard: 50 h.p. Gnome. The eight machines built for Russia had the 70 h.p. Gnome, as had the three improved Military Box-kites, which also had the small nacelle. Other engines fitted were the 50 h.p. Gregoire, 50 h.p. E.N.V. and the 60 h.p. Renault.
  Dimensions: Span: 33 ft (46 ft 6 in. with extensions). Length: 38 ft 6 in. Height: 11 ft. Chord: 6 ft 7 in. Gap: 6 ft 8 in. Stagger: nil. Dihedral: nil. Span of tail: 8 ft. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: 457 sq ft (517 sq ft with extensions). Tailplanes: 89 sq ft. Rear elevator: 22-5 sq ft. Forward elevator: 30-5 sq ft. Rudders: 26-5 sq ft.
  Weights: Loaded: 900 lb.
  Performance: Maximum speed: 40 m.p.h.
  Tankage (Military Type): Petrol: 19 gallons. Oil: 9 gallons.
  Service Use: No. 2 (Aeroplane) Company, Air Battalion, Royal Engineers, later No. 3 Squadron, R.F.C. R.N.A.S. flying schools at Eastchurch, Hendon and Eastbourne. Also used at Bristol flying schools at Larkhill and Brooklands, and by Eastbourne Aviation Co.
  Production: Standard Box-kite: 16. Extended Box-kite: 5. Military Box-kite: 40. Military Box-kite trainer (60 h.p. Renault): 2. Military Box-kite, 70 h.p. Gnome (for Russia): 9. Improved Military Box-kite (with nacelle): 4. Total production: 76.
  Serial Numbers: 12, 24, 942-947 (built under Contract No. C.P.56037/14/x.)

Bristol T.B.8 and G.B.75

  THE full history of the Bristol T.B.8 is a varied and interesting one. The type underwent many modifications in the course of development; so much so that it appeared to exist in several different forms.
  The designation T.B.8 was derived from the initial letters of the words Tractor Biplane and from the first digit of the nominal horse-power of the standard engine, the 80 h.p. Gnome.
  The first T.B.8 was a biplane conversion of the monoplane designed by Coanda for the 1912 Military Trials. The basic airframe on which the conversion was made was that of the Coanda monoplane which had the Bristol works Sequence No. 121. Two-bay biplane wings were fitted, and wing-warping was used for lateral control; the aeroplane retained the characteristic four-wheel undercarriage and Coanda tail unit. The first T.B.8 was test-flown on Salisbury Plain during July and August, 1913, by Howard Pixton and Henri Jullerot, and proved to be satisfactory.
  Bristol No. 121 had a varied career, for it was soon converted to a seaplane. To provide it with floats, use was made of the large single float which had been designed by Oscar Gnosspelius for the Coanda seaplane, Bristol No. 120. (This earlier seaplane had been exhibited at Olympia, where it was ordered by the Admiralty and had been officially numbered 15. The Gnosspelius float was replaced by a Saunders float in April, 1913, but on the 15th of that month the Bristol seaplane was wrecked.) The Gnosspelius float was divided down the centre line to form two separate floats; a tail float, water rudder, and fin surfaces were added to the T.B.8; and the modified machine was sent to Dale for test on September 20th, 1913.
  After being successfully flown by Harry Busteed and G. Bentley Dacre, No. 121 was sent back to the British & Colonial Aeroplane Co.’s workshops in December. There it was rebuilt and re-emerged with the new works number 205. It was delivered to the Admiralty on January 2nd, 1914, and was thereupon allotted the official serial number originally earmarked for the ill-fated machine which had provided its floats: No. 15.
  The seaplane was flown at Calshot, but was found to fly tail-high and was returned to the manufacturers for modification in February, 1914. The stagger was increased, ailerons replaced wing-warping, and a single large fin was fitted above the fuselage in place of the original upper and lower fins.
  The Admiralty were so pleased with this T.B.8 seaplane that they ordered two more, to which the official serial numbers 147 and 148 were allotted. Later, the Admiralty wanted the two machines to be enlarged and fitted with the 200 h.p. Salmson engine. The manufacturers declined to do so, but in the meantime sold the Admiralty two T.B.8 landplanes, Nos. 43 and 153.
  No. 153 had originally been a special machine which was exhibited at the Paris Aero Salon in November, 1913. It then had a bomb rack containing twelve bombs which could be released singly or simultaneously, and a bomb sight was fitted. After its return from Paris, this T.B.8 was given a plain vee undercarriage and was delivered to Eastchurch on March 19th, 1914.
  The T.B.8 proved to be so successful that towards the end of 1913 several of the Coanda monoplanes which had been supplied to Italy, Germany and Roumania were returned for conversion to T.B.8s. Six of these converted machines were returned to Roumania, where they saw active service during the Balkan wars; and one was delivered to the Admiralty. This last machine was No. 43, and had a plain vee undercarriage. Up to this time all T.B.8s had had the 80 h.p. Gnome engine.
  Some examples of the early T.B.8 were built under licence in France by the Breguet company, and were powered by the 80 h.p. Le Rhone engine. A sample Bristol-built T.B.8 was modified to have the Le Rhone and was sent to Villacoublay on March 4th, 1914. It crashed on completion of the French official trials, but was taken back to the works at Bristol, rebuilt with an 80 h.p. Gnome, and was ultimately delivered to the R.N.A.S. at Eastchurch on September 17th, 1914, with the official serial number 916.
  With it went No. 917, a T.B.8 which had been flown in Spain late in 1913; had been rebuilt with an 80 h.p. Clerget engine; was later fitted with a 100 h.p. Gnome Monosoupape and sent to the Vienna competition on June 10th, 1914; returned on July 30th; was fitted with an 80 h.p. Gnome, and was delivered to the R.F.C. at Farnborough on August 6th. It was given the official serial number 620, was rejected by the A.I.D. on August 19th, but was subsequently accepted by the Admiralty and renumbered 917. In similar case was No. 948, which had been No. 614 before rejection by the A.I.D.
  It seems probable that a similar fate befell the twelve T.B.8s which were ordered by the War Office on August 4th, 1914. The serial numbers 691-702 were allotted for these aircraft and some at least bore their original numbers. Deliveries began on September 26th, 1914. The entire batch was diverted to the Admiralty, however, and the T.B.8s were then renumbered 1216-1227.
  Some of the R.N.A.S. machines had modified undercarriages: the front wheels were removed, the chassis lengthened by 4 1/2 inches, and the main wheels moved six inches forward. On the later T.B.8s ailerons took the place of wing-warping, and a full-circular open-fronted cowling replaced the semi-enclosed engine cowling which had been fitted to earlier machines. The tail-unit was also completely redesigned: the rudder had a rounded outline and extended to the bottom of the fuselage, and divided elevators were fitted.
  Contemporary with the “pure” T.B.8s was a slightly different type of Bristol two-seat biplane which later came to be regarded more or less as a T.B.8. Designated Bristol G.B.75, this biplane first appeared at the Aero Show of 1914 held at Olympia in March of that year. It was a development of the basic T.B.8 design and was of similar general appearance, having two-bay wings and the characteristic Coanda four-wheel undercarriage. In the design of the fuselage, considerable care was taken to reduce drag: the 80 h.p. Gnome Monosoupape engine was completely enclosed, and a large blunt spinner was fitted to the airscrew. The spinner had twelve louvres to admit cooling air. The rounded contours of the spinner were continued along both top and bottom of the fuselage by fairings. The G.B.75 a and rudder of unique appearance, quite unlike any vertical tail assembly fitted to the T.B.8.
  The G.B.75 had not flown at the time of its appearance at Olympia. Its first flight was made at Larkhill on April 7th, 1914, but modifications had to be made almost immediately. As might have been expected, the enclosed engine installation was not a success: the spinner was removed, and a new cowling was fitted. The stagger of the mainplanes was also increased. In its modified form, the G.B.75 Aew again on April 28th, 1914.
  The War Office was interested in the G.B.75, and began negotiations for its purchase soon after the Olympia show. The aircraft was finally delivered to the R.F.C. at Farnborough on August 2nd, 1914. It was given the official serial number 610 but, as the illustration shows, a painter’s error temporarily gave the machine the false identity of No. 601 (which number rightly belonged to a B.E.2a).
  One Bristol T.B.8 went to France on August 28th, 1914, as part of the equipment of the Eastchurch Squadron of the R.N.A.S. under Commander C. R. Samson; and two more were sent to the unit in October. One was shot down over Dixmude before reaching the squadron, however. One of the unit’s T.B.8s bombed batteries at Middelkerke on November 25th, 1914.
  No. 1 Squadron, R.N.A.S., was formed at Gosport in October, 1914, and the first complete Flight was equipped with four T.B.8s. On November 18th this Flight was sent to Newcastle-on-Tyne for coastal reconnaissance duties. The T.B.8 Flight remained at Newcastle and was eventually detached from No. 1 Squadron. When No. 1 Naval went to France on February 26th, 1915, its equipment included one T.B.8.
  The T.B.8 proved to be suitable for use as a trainer, and some had been used in that capacity at Hendon and Gosport. In August, 1915, twenty-four were ordered for the R.N.A.S. specifically for training duties. These were the last T.B.8s to be built, and were constructed at the Brislington works of the British & Colonial Aeroplane Company.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Other Contractors: Societe Anonyme des Ateliers d’Aviation Louis Breguet, Velizy per Chaville (Seine et Oise), and at Villacoublay.
  Power: 80 h.p. Gnome; 80 h.p. Le Rhone; 80 h.p. Clerget; 100 h.p. Gnome Monosoupape.
  Dimensions: Span: 37 ft 8 in. Length: 29 ft 3 in. Chord: 6 ft 1 in. Span of tail: 8 ft 9 in. (early version).
  Areas: Wings: 450 sq ft.
  Weights: Empty: 970 lb. Loaded: 1,665
  Performance: Maximum speed: 75 m.p.h. Initial rate of climb: 573 ft per min. Climb to 3,000 ft: 11 min. Endurance: 5 hours.
  Service Use: France: No. 1 Squadron, R.N.A.S.; Eastchurch Squadron of R.N.A.S. Coastal Reconnaissance: Detached Flight of No. 1 Squadron, R.N.A.S., at Newcastle-on-Tyne. Training: No. 2 Squadron, R.N.A.S., Gosport; R.N.A.S. Training School at Hendon. Also used by the Roumanian Army.
  Production and Allocation: Twelve T.B.8s were produced by reconstructing various Coanda monoplanes: one of these was the seaplane and another was a side-by-side two-seater built for the Bristol School of Flying. Six were sent to Roumania; one was sold to R. P. Creagh; and the side-by-side T.B.8 went to Larkhill. The seaplane was delivered to the R.N.A.S. with serial number 15; one of the three remaining landplane T.B.8s (serial number 43) had been delivered to the R.N.A.S., Eastchurch, on April 29th, 1914; another was sent to Farnborough on August 3rd, 1914, but was transferred to the R.N.A.S. on August 27th; and the third went to Farnborough on August 6th, 1914, but was transferred to Eastchurch on September 16th, 1914, with the serial number 917. The T.B.8 rebuilt from the G.B.75 was delivered to Farnborough on August 2nd, 1914.
  Three other early T.B.8s were built. The 1913 Paris Salon machine was delivered to the R.N.A.S. on March 19th, 1914, serial number 153; the Breguet demonstration machine was sent to the R.N.A.S. on September 17th, 1914, serial number 916; the other was sent in skeleton form to the Breguet works.
  The first true production batch of twelve were diverted to the R.N.A.S.: two were sent to Gosport and three to Eastchurch. The twenty-four T.B.8s of the second production batch were built for the R.N.A.S. in 1915 and early 1916.

Total production, including rebuilds: 52
Deliveries to R.F.C.: 3 (two later transferred to R.N.A.S.)
Deliveries to R.N.A.S.
1 seaplane
31 landplanes
14 diverted from R.F.C.

  Serial Numbers: 15 (seaplane); 43; 153 (supplied under Contract No. C.P.36217/14/x); 610, the Bristol G.B.75; 614, renumbered 948; 620, renumbered 917; 691-702, ordered for the R.F.C. under Contract No. A.2594, but diverted to the R.N.A.S. under Contract No. C.P.63528 and renumbered 1216-1227; 916 and 917 (formerly 620), supplied under Contract No. C.P.53505/14/x; 8442-8453 and 8562-8573, supplied under Contract No. C.P.57306/15/x.

Bristol Scout

  IN October, 1911, Lieutenant C. D. Burney, R.N., interested the British & Colonial Aeroplane Co. in his ideas for marine aircraft with multiple hydrofoils below the hull. Two months later Frank Barnwell joined the company as a designer, and his first job was to translate Lieutenant Burney’s ideas into practice. For this purpose the company installed him in a special drawing office known as X Department, at No. 4 Fairlawn Avenue, Bristol, quite separate from the main drawing office. There he was joined on January 4th, 1912, by Clifford W. Tinson, who was his assistant on the development of the Burney machines.
  This work was abandoned in September, 1913, but X Department did not, as might have been expected, thereafter come under the control of Henri Coanda, who had joined the company in March, 1912, and was regarded as the Chief Designer.
  Barnwell’s next activity was the design of a small single-seat biplane. This work was carried out in considerable secrecy, and the original drawings were made in an ordinary manifold book; simple carbon copies were taken and were sent to the shops for use as working drawings. At about this time (November, 1913) the company turned over to Barnwell the fuselage of a partly-built Coanda monoplane on which construction had been abandoned because it was proving to be heavier than had been expected.
  This monoplane had been allotted the Bristol works Sequence Number 183. For some reason best known to the manufacturers this number was, for a time at least, used when referring to Barnwell’s little single-seat biplane; and it was frequently called S.N. 183 despite the fact that its own works Sequence Number was 206. This may have been done in order to avoid offending Coanda in any way, but the fact remains that the little biplane was entirely the work of Frank Barnwell.
  The completed machine emerged in February, 1914, and was a single-bay biplane with wings of only 22 feet span; the engine was an 80 h.p. Gnome rotary. The general appearance of this little aeroplane was one of pleasing simplicity, and its small size earned it the name of the Bristol Baby Biplane or Scout.
  The Scout was tested by Harry Busteed at Larkhill on February 23rd, 1914, and was an immediate success. Its maximum speed was 97 m.p.h. and the initial rate of climb 800 feet per minute. During the next month it was exhibited at the Aero Show at Olympia, where it created a furore: it was then still in its original form with an engine cowling which covered most of the front of the engine.
  In May the Scout was fitted with larger wings which had a span of 24 ft 7 in.; and a full circular, open-fronted engine cowling replaced the original: the new cowling had six external stiffening ribs. Thus modified, the Scout was raced against the more powerful Sopwith Tabloid at Brooklands, and lost only by the narrowest of margins. The Bristol was therefore expected to do well in the 1914 Aerial Derby, which was to be held on May 23rd. Bad weather led to the postponement of the contest until June 6th, but visibility on the day of the race was so bad that S. V. Sippe, who was to have flown the Scout in the race, was forbidden to take off.
  One of the competitors who unsuccessfully braved the weather was Lord Carbery. On June 8th he asked Mr Sippe for permission to fly the Bristol Scout, and took such a liking to the little machine that he wanted to buy it immediately. The manufacturers readily agreed to the sale, for they were then building two more Scouts.
  Lord Carbery fitted the Scout with an 80 h.p. Le Rhone engine taken from his Morane-Saulnier monoplane, and flew it in the Hendon-Manchester-Hendon race on June 20th, 1914. Unfortunately, he damaged the machine at Castle Bromwich and had to withdraw; but by July 7th the Scout was once more airworthy, and four days later he flew it in the London-Paris-London race. After a somewhat hair-raising take-off from Hendon with petrol for five hours’ flight and an engine which was not giving full revs per minute, Carbery reached the French turning-point at Buc. On the return journey his engine stopped suddenly in mid-Channel, and he came down on the water beside a tramp steamer. The pilot escaped without so much as a wetting, but over-energetic efforts to salve the aeroplane pulled the engine and bearers away from the airframe, which dropped back into the Channel and was lost.
  By the time the two new Bristol Scouts were completed, Britain was at war. The two machines were delivered to Farnborough on August 21st and 23rd, 1914, and were sent to join the R.F.C. in France after trials at the Royal Aircraft Factory. These two machines were designated Bristol Scout B to distinguish them from the original Scout, or Scout A, from which they differed in detail only. The Scout B had an 80 h.p. Gnome engine; the flying-wires were duplicated; the rudder was slightly larger; the undercarriage track was increased; the cables connecting upper and lower ailerons were farther apart; and wing-tip skids were mounted directly under the interplane struts. The engine cowling was generally similar to that of the modified Scout A, but the diameter of the frontal opening was reduced.
  The Scouts B went to France in the first week in September, 1914. One was attached to No. 3 Squadron, where it was flown by Lieutenant Chohnondeley; and the other was flown by Major J. F. A. Higgins of No. 5 Squadron. The Scout belonging to No. 3 Squadron was armed with two rifles: one was mounted on each side of the fuselage at an outward angle of 45 0 in order to clear the airscrew.
  The first contract for production of the Bristol Scout was placed on November 5th, 1914, and was for twelve machines (numbered 1602-1613) for the R.F.C.: this was followed on December 7th by an order for twenty-four (numbered 1243-1266) for the R.N.A.S. These were designated Scout C, and were virtually identical to the Scout B. The engine cowling of the Scout C had no external stiffening ribs, and, in the Scouts C which had the 80 h.p. Gnome, the oil tank was installed behind the cockpit. The machines of the R.F.C. batch were delivered in March, 1915, and a further contract for seventy-five Scouts (numbered 4662-4699 and 5291-5327) was placed.
  The Bristol Scout never formed the complete equipment of any R.F.C. unit in any theatre of war, for it was in use at a time before the grouping of single-seat scouts into homogeneous squadrons. Each squadron had one or two fighting scouts on its strength for the protection of the two-seat reconnaissance machines.
  The Order of Battle of the R.F.C. on March 10th, 1915, shows that no Bristol Scouts were with the squadrons in the field on that date, and by May 9th only one was on active service in France: it was with No. 4 Squadron. On September 25th there were only nine on the strength of the squadrons, but thereafter nearly every squadron had at least one Scout, until the type began to be withdrawn. By the time of the opening of the Somme offensive on July 1st, 1916, only Squadrons Nos. 11 and 24 had Bristol Scouts on their strength: each unit had three. Altogether, eighty Scouts went to France.
  The number in operational use was never very large, but it was on a Bristol Scout that Captain Lanoe G. Hawker of No. 6 Squadron won the first Victoria Cross to be awarded for an air-to-air combat. His machine was armed with only' a single-shot cavalry carbine, mounted at an outward angle on the starboard side of the fuselage; yet on the evening of July 25 th, 1915, he attacked three enemy two-seaters in succession. The first he drove down; the second dived away with a damaged engine; and the third, an Albatros two-seater, fell in flames. All three enemy machines were armed with machine-guns.
  More Scouts were ordered during 1915 for both the R.F.C. and the R.N.A.S. Shortage of 80 h.p. Gnomes led to that type of engine being reserved for Scouts destined for the R.N.A.S.; whilst many of the R.F.C. machines were fitted with the 80 h.p. Le Rhone. This was done because the R.N.A.S. machines were liable to have to fly over the sea, and the Gnome was regarded as the more reliable power unit. In the Le Rhone installation, the oil tank was mounted in front of the cockpit, for it was discovered that the oil pump of the Le Rhone was less efficient than that of the Gnome, and with the oil tank in the original position (behind the pilot’s seat) the engine was starved of oil in a climb. Another alternative engine which was fitted to some Scouts C when the Gnomes ran short was the 80 h.p. Clerget rotary. Martlesham tests of a Clerget-powered Scout were carried out in March, 1916.
  Further modifications were made to the design, and a fourth version, designated Scout D, appeared late in 1915. This variant had shorter ailerons, increased dihedral, and the wing-tip skids were further outboard. The first production batches of Scouts D had the 80 h.p. Le Rhone: eighty machines of this type were built, and all went to the R.F.C.
  The final production version of the Bristol Scout D had the 100 h.p. Gnome Monosoupape engine. A larger diameter engine cowling had to be fitted, and there was a “gumboil” bulge on the starboard side of the cowling. The bulge was made to expedite the escape of the exhaust gases from the interior of the cowling. It was found, however, that the Monosoupape engine vibrated and caused the centre-section tanks to leak; and the last twenty machines (N.5400-N.5419) of the final batch for the R.N.A.S. had the 80 h.p. Gnome.
  These versions of the Scout D had a vee-shaped cut-out in the trailing edge of the centre-section in which there was a bracket for a semi-free Lewis gun.
  Another version of the Bristol Scout existed, and is sometimes regarded as a Scout D: in reality, however, the machines concerned were modified Scouts C. These were the Scouts which had the 110 h.p. Clerget engine. At least three Bristol Scouts had this power unit. No. 5554 was the first; its Clerget was installed when the machine was rebuilt after a crash at C.F.S. The second Scout with the 110 h.p. Clerget was No. 5555, and the opportunity was taken to use this machine as a flying test-bed for the engine installation for the Bristol M. 1A monoplane; the airscrew had an enormous shallow spinner which covered almost all of the engine. The engine diameter exceeded the width of the fuselage, and consequently the cowling had to be tapered back markedly. No. 5556 also had the 110 h.p. Clerget, and was fitted with a conical spinner; this spinner distorted badly at full engine speed and caused severe vibration.
  There was also a Scout D, flown by Lieutenant F. T. Courtney, which had a cowling similar to that of No. 5555, but the airscrew had a spinner which must have come from a Morane-Saulnier aircraft (probably a Type BB biplane or Type LA parasol monoplane). The engine of this Scout appeared to be a 110 h.p. Le Rhone, probably also from the same Morane-Saulnier, and the installation must have been a “home-made” modification.
  A few of the Scouts D which were delivered to the R.F.C. early in 1916 were armed with a fixed Vickers gun, synchronised to fire through the revolving airscrew by means of the Vickers-Challenger interrupter gear. The first of these machines reached France on March 25th, 1916. The date is of considerable significance, for it was not until two weeks later, on April 8th, 1916, that a sample of the Fokker interrupter gear fell into our hands when a Fokker monoplane made a forced landing in the British lines. Some of the Bristol Scouts delivered to the R.N.A.S. had a Vickers gun with the Scarff-Dibowski interrupter gear.
  After its operational service in France, the Scout was extensively used at training units at home, in Egypt, and in Australia. In Macedonia, No. 47 Squadron had at least one Bristol Scout late in 1916; and some of the Scouts which went to the Middle East were used operationally by Squadrons Nos. 14, 67 and 111 in Palestine. A few Bristol Scouts were sent from Egypt to assist No. 30 Squadron in Mesopotamia. These machines were assembled at Basra, and two of them were flown to the front, 750 miles away, on April 5th and 17th, 1917. On April 22nd, Lieutenant M. L. Maguire, flying a Bristol Scout, shot down a Halberstadt behind Istabulat. The last Scouts in Mesopotamia were those used as part of the equipment of No. 63 Squadron’s fighter Flight at Samarra: these were still in service in November, 1917.
  The Bristol Scout was also widely used by the R.N.A.S., both operationally and for training purposes. One of the lesser-known distinctions which can be claimed for the Scout is that it pioneered deck-flying from aircraft carriers. A small seaplane carrier, the Vindex, had been fitted with a flying deck forward, and the first take-off from the vessel was made by Flight-Lieutenant H. F. Towler in a Bristol Scout on November 3rd, 1915. It was found that, with Vindex steaming at 25 kt in a dead calm, the take-off run was but 30 ft; with the ship making 13 kt the run was 102 ft. Two Scouts could be accommodated on board, and they were dismantled for stowage in their hangar: flights could not, therefore, be made at short notice. There were no facilities for retrieving the Scouts after flight, though the machines were ultimately provided with air bags to keep them afloat after ditching.
  The carrier-borne Bristol Scouts were intended to be used against Zeppelins, and on August 2nd, 1916, Vindex put to sea from Harwich when news was received that a Zeppelin raid was expected. At about 7 p.m. a Bristol Scout piloted by Flight-Lieutenant C. T. Freeman flew off to attack a Zeppelin which had been sighted earlier. Freeman attacked the nearer of two airships which he found, and three times dropped Ranken darts upon it. He scored a hit on his third attack, but did not succeed in destroying the Zeppelin, which turned back to Germany. The Scout’s engine would not pick up after the engagement, and Freeman had to come down on the sea, where the air bags kept his machine afloat long enough for him to be rescued by a Belgian ship bound for Holland. There he was interned, but was released as a shipwrecked mariner after a few days.
  Some months before Freeman’s exploit, one of the Vindex Scouts (a Scout C, No. 3028) took part in a remarkable experiment at Felixstowe, the object of which was to provide a speedier means of transporting a fighter aircraft to within striking distance of Zeppelins. The “carrier” in this case was a Porte Baby flying boat, and the Bristol Scout was carried on its upper wing. The Scout’s undercarriage was in front of the leading edge of the flying boat’s wing; the wheels rested in special crutches carried on struts from the engine bearers of the Baby’s central engine, and the tail-skid was secured by a quick-release hook controlled by the pilot of the Scout.
  A successful flight and mid-air separation was made on May 17th, 1916. The Bristol Scout was flown by Flight-Lieutenant M. J. Day, and the Porte boat by its designer, Squadron Commander John Porte. The Bristol Scout took no active part in the take-off, and it was not until the combination reached a height of 1,000 feet above Harwich that Day switched on and climbed away successfully. The experiment was never repeated.
  As an anti-Zeppelin fighter the Bristol Scout was used by the R.N.A.S. from various aerodromes in England, but never succeeded in coming to grips with the enemy.
  The Bristol Scout was used by the R.N.A.S. during the Dardanelles campaign, and continued to be used in the Aegean area after the evacuation. When No. 2 Wing, R.N.A.S., went to Imbros at the end of August, 1915, among its equipment were four Scouts; and six more, armed with Lewis guns, arrived later in the year. A year later, some Bristol Scouts were still being flown by No. 2 Wing at Imbros and from Thasos by the composite R.N.A.S. unit known as “A” Flight: on December 13th, 1916, one of No. 2 Wing’s Scouts escorted four Henri Farmans on a bombing attack on the railway bridge across the River Maritsa at Kuleli Burgas.
  One hundred and fifteen Bristol Scouts were delivered to R.F.C. training units during the war. Their numbers dwindled steadily, until at the last the few which remained were the jealously-guarded personal aircraft of senior officers. The Scout was very popular with pilots, for it combined excellent handling qualities with great structural strength. Only the lack of timely, adequate and effective armament prevented it from making a great name for itself during the war.
  One solitary specimen survived the Armistice. This was a Scout C, No. 5570, whose first owner was Major J. A. McKelvie: its civil registration was G-EAGR. After changing owners more than once, this last Bristol Scout ended its days on a scrap-heap at North Cave.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Power: Scout A: 80 h.p. Gnome, later 80 h.p. Le Rhone. Scout B: 80 h.p. Gnome. Scout C: 80 h.p. Gnome;
80 h.p. Le Rhone; 80 h.p. Clerget; 110 h.p. Clerget. Scout D: 80 h.p. Le Rhone; 100 h.p. Gnome Monosoupape; 80 h.p. Gnome. At least one Scout D had a 110 h.p. Le Rhone.

Dimensions:
Scout A Scout B Scout C Scout D
ft. in. ft. in. ft. in. ft. in.
Span 22 - 24 7 24 7 24 7
Length 19 9 20 8 20 8 20 8
Height - - 8 6 8 6 8 6
Chord 4 - - - 4 6 4 6
Gap - - - - 4 3 4 3
Stagger 1 4 - - 1 4 1/2 1 9
Span of tail 8 - - - - - 10
Wheel track 3 3 - - - - - -
Airscrew diameter:
80 h.p. Gnome 8 - - - 8 2 1/2 - -
80 h.p. Le Rhone - - - - - - 8 8
80 h.p. Clerget - - - - 8 3 - -
110 h.p. Clerget - - - - 8 6 3/4 - -
Dihedral - - 1° 45' 3°
Incidence - - 2° 2° 30'
Areas (sq ft):
Wings 161-5 198 198 I98
Each aileron - - - 5-8
Total aileron - - - 23-2
Tailplane 15 - 23 23
Elevator 13 - 15 15
Rudder 5 - 7 7

  Armament: Originally none was fitted. Some pilots carried a rifle, pistol, or cavalry carbine. Some Bristol Scouts had a Lewis machine-gun mounted on the starboard side of the fuselage just in front of the cockpit, pointing outwards to clear the airscrew. Other machines had a Lewis gun mounted above the centre-section; specific provision for such an installation was made on some Bristol Scouts D. In some cases a 0-45-in. Martini-Henry rifle firing incendiary-filled lead bullets was used, and a few machines were armed with a duck gun firing chain shot.
  Anti-Zeppelin R.N.A.S. Scouts had two containers of Ranken darts directly under the pilot’s seat; each container had twenty-four darts.
  Late Scouts D had a fixed forward-firing Vickers machine-gun, synchronised by Challenger gear or by the Scarff-Dibowski gear to fire through the revolving airscrew.

Weights (lb) and Performance:
Aircraft Scout A Scout C Scout D
Engine 80 h.p. 80 h.p. 80 h.p. 110 h.p. 80 h.p. Monosoupape
Gnome Le Rhone Clerget Clerget Le Rhone
No. of Trial Report - M.55 - M.21 - -
Date of Trial Report - June, 1916 March, 1916 May, 1916 - -
Type of airscrew used on trial - P.3001 P.2408 P.3010 - -
Weight empty 617 757 750 926 760 -
Military load - 80 Nil 73 60 -
Pilot - 180 170 160 180 -
Fuel and oil - 178 169 256 200 -
Weight loaded 957 1,195 1,089 1,415 1,250 1,250
Maximum speed (m.p.h.) at:
ground level 95 92-7 93-8 107-3 100 -
1,000 ft - 92-5 - - - -
3,000 ft - 91 - 109 - -
5,000 ft - 90-5 - 108 94 -
6,500 ft - 89 - 108 - -
7,000 ft - 88 - 108 - -
8,000 ft - - 70 106 - -
9,000 ft - 86 - 103 - -
10,000 ft - 86-5 - - 86 -
I 1,000 ft - 87 - - - -
m. s. m. s. m. s. m. s. m. s. m. s.
Climb to
1,000 ft 1 15 0 55 1 38 1 00 - - - -
2,000 ft - - 2 05 2 53 2 15 - - - -
3,000 ft - - 3 35 4 38 3 35 - - - -
4,000 ft - - 5 20 6 18 5 05 - - - -
5,000 ft - - 7 00 8 05 6 30 - - - -
6,ooo ft - - 9 30 10 13 8 30 - - - -
6,500 ft - - 10 50 11 30 9 30 - - - -
7,000 ft - - 12 10 12 45 10 30 - - - -
8,000 ft - - 14 55 16 45 12 45 - - - -
9,000 ft - - 18 00 21 15 15 05 - - - -
10,000 ft - - 21 20 27 30 18 15 18 30 - -
I 1,000 ft - - 25 05 - - - - - - - -
12,000 ft - - 29 30 - - - - - - - -
13,000 ft - - 33 00 - - - - - - - -
14,000 ft - - 41 30 - - - - - - - -
15,000 ft - - 50 00 - - - - - - - -
Service ceiling (feet) - 15,500 11,000 14,000 - -
Endurance (hours) 3 2 1/2 2 2 1/2 - -
Tankage (gallons):
Petrol - 16 16 26 - 27
Oil - 6 6 6 - 5 1/2

  Service Use: Western Front: R.F.C. Squadrons Nos. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 18, 21, 24 and 25. Palestine: R.F.C. Squadrons Nos. 14, 67 (Australian), and 111. Mesopotamia: R.F.C. Squadrons Nos. 30 and 63. Macedonia: R.F.C. Squadron No. 47. Dardanelles: No. 2 Wing, R.N.A.S., Isle of Imbros; “A” Flight, R.N.A.S., Isle of Thasos. Australia: presumably used at Australian F.C. Central Flying School, Point Cook, Werribee, Victoria. Seaplane Carrier Vindex: two Bristol Scouts. Training: Widely used at training aerodromes: e.g. No. 34 Reserve Squadron, Orfordness; No. 45 Squadron, working-up before going overseas; training squadron at Dover; 20th Training Wing, Abu Qir, Egypt; flown at Shoreham and London Colney. Also used by the R.N.A.S. at various aerodromes: e.g. Great Yarmouth, Redcar, Chingford, Port Victoria, East Fortune, Cranwell, and at the R.N.A.S. Flying School, Vendome.
  Production and Allocation: The different versions of the Bristol Scout were built in the following numbers:
Scout A: 1.
Scout B: 2.
Scout C: 211. Of that total, 137 were delivered to the R.F.C. and seventy-four to the R.N.A.S.
Scout D, 80 h.p. Le Rhone: eighty, to R.F.C. only.
Scout D, 100 h.p. Gnome Monosoupape: sixty, to R.N.A.S. only.
Scout D, 80 h.p. Gnome: twenty, to R.N.A.S. only.
  These figures represent original deliveries. According to official statistics, however, the R.F.C. received 236 Bristol Scouts: this appears to indicate that seventeen must have been transferred from the R.N.A.S. Eighty went to France, thirty-two to the Middle East Brigade, nine to Home Defence units, and 115 to training units. The remainder went to the R.N.A.S., and precise allocation details are not known.

Bristol F.2A and F.2B

  IN March, 1916, Captain Barnwell started work on the design of a two-seat tractor biplane which was intended to be a replacement for the B.E. two-seaters as a reconnaissance aircraft. Additionally, the new type was to be capable of carrying out fighting patrols.
  The designation Bristol R.2A was applied to this design, which was based on the 120 h.p. Beardmore engine. Dual controls were to be fitted, and a camera and wireless were included in the machine’s equipment. The wings were of 40 ft 8 in. span, and the fuselage was to have been mounted mid-way between them in order to bring the pilot’s eyes level with the upper wing. The designed armament consisted of two Lewis guns: one was fixed on the starboard upper longeron and was synchronised to fire forward through the airscrew, while the observer had a Scarff ring-mounting for his gun.
  It was recognised that the R.2A would be underpowered with the 120 h.p. Beardmore, and Captain Barnwell considered the substitution of a Hispano-Suiza. However, a new Rolls-Royce vee-twelve engine, later to achieve fame as the Falcon, became available at this time.
  In configuration, size and output the Falcon was ideal for Barnwell’s purpose, but with characteristic thoroughness he did not merely modify the R.2A to accommodate the new engine: he produced what was virtually a new design which took full advantage of the Rolls-Royce engine. This new design was designated Bristol F.2A. The fuselage remained in the mid-gap position: thus the pilot had the widest possible field of vision. A single fixed Vickers gun was mounted under the cowling, on the aircraft’s centre-line. The fuselage itself was redesigned to terminate aft in a horizontal knife-edge, and the tail-unit also underwent revision. Thus the observer was given a wide field of fire for his Lewis gun, for he could fire forwards over the upper wing with very little elevation of his gun, and the downward sweep of the top of the fuselage left very little blind area to the rear. The aeroplane was essentially a fighter, and Fighter it was called.
  The initial order was for two prototypes, one with the Rolls-Royce Falcon Mk. I, the other with the 150 h.p. Hispano-Suiza engine. Construction was begun in July, 1916, and the first prototype, A.3303, was completed by September 9th.
  In its original form A.3303 had two long vertical radiators, one on either side of the fuselage; there were short exhaust manifolds with forward outlets, and the engine drove a substantial four-bladed lefthand airscrew. It was soon found that the radiators obscured part of the pilot’s field of vision, particularly for landing. They were therefore replaced by a flat radiator of more or less circular shape installed in the nose of the fuselage, which was modified to conform to the contour of the new radiator. The exhaust manifolds were revised to provide a rear outlet for the gases, and the machine was later flown with a two-bladed left-hand airscrew.
  The second prototype A.3304, which had the 150 h.p. Hispano-Suiza engine, was ready for flight testing by October 25th, 1916, and was fitted with a circular nose-type radiator from the beginning. A minor point of difference between the two prototypes was that A.3304 had its tail-skid built into the base of the rudder, whereas the first machine had a pylon-type unit generally similar to that of the B.E. biplanes.
  Both prototypes had mainplanes similar in plan to those of the B.E.2C, and neither had the lower centre-section covered in: the lower wings were attached to an open cross-braced steel tube structure which was known as the wing anchorage frame. Each prototype originally had a vertical end-plate at the inboard end of each lower mainplane, but these surfaces were later removed. In both prototypes the pilot’s seat was armoured.
  The Bristol F.2A passed its official trials with complete success, and returned performance figures which were better than the estimates. Fifty production machines were ordered, powered by the Rolls-Royce Falcon, since no Hispano-Suizas were available: at that time all available engines of the latter type were wanted for S.E.5s.
  The production F.2As, numbered A.3305 to A.3354, were almost identical to the second form of A.3303, but the plan-form of the wing-tips was modified to a simpler, blunt outline which remained standard on all succeeding variants. The lower centre-section remained an open structure, and a two- bladed right-hand airscrew was used. No armour was fitted to the pilot’s seat in production F.2As.
  An R.F.C. training squadron was set up at Rendcombe to provide pilots and observers with familiarisation on the new Bristol Fighter, and the first unit to take the machine to France was No. 48 Squadron, which arrived there on March 8th, 1917, and settled down at Bellevue. The squadron’s first offensive patrol was made on April 5th, 1917, but proved to be a disastrous debut for the Bristol.
  The patrol consisted of six F.2As and was led by Captain W. Leefe-Robinson, V.C. When over Douai, they were attacked by five Albatros D.IIIs led by Manfred von Richthofen, who shot down two of the Bristols for his thirty-fifth and thirty-sixth victories. Two other Bristols, one of them flown by Leefe-Robinson himself, were accounted for by Richthofen’s pilots. In his combat report Richthofen wrote of A.3340, which, flown by Lieutenant A. M. Leckler (observer, Lieutenant H. D. K. George), was the first of the two F.2As he shot down:
  “It was a new type of aeroplane, which we had not known before, and it appears to be quick and rather handy, with a powerful motor, V-shaped and twelve-cylindered. Its name could not be recognised.
  “The D.III Albatros was, both in speed and ability to climb, undoubtedly superior.”
  By April 16th, eight more Bristol F.2As had been lost (five of them through overstaying their patrol and running out of fuel), and opinion at R.F.C. Headquarters must have been somewhat similar to Richthofen’s judgment.
  But the fault lay not in the Bristol. In its earliest days, its crews, Leefe-Robinson’s patrol included, made the serious tactical error of flying the machine in the accepted manner of the time for two-seaters; namely, as a platform for the observer’s gun. They failed to recognise the Bristol’s supreme combat virtues of manoeuvrability and structural strength.
  Fortunately, one or two pilots began more or less experimentally to fight the Bristol in the single-seater fashion, using the front gun as the primary weapon and leaving the observer to protect the tail. These tactics were immediately successful, and were forthwith adopted by No. 48 Squadron and by No. 11, the second unit to receive Bristol Fighters. The leading exponent of the Bristol Fighter was Lieutenant A. E. McKeever of No. 11 Squadron, who opened his scoring on June 29th, 1917, by shooting down an Albatros Scout. McKeever shot down thirty enemy aircraft, and won nearly all of his victories on the Bristol Fighter.
  The first weeks of operational flying indicated certain desirable modifications, chief among which was the need to improve the pilot’s forward view. This was achieved by sloping the upper longerons downwards from the front of the observer’s cockpit to the level of the engine bearers: this modification permitted the installation of a larger fuel tank and cowling with a narrower top. The modified fuselage was tested on A.3304, the second F.2A prototype, which retained its Hispano-Suiza engine. At the same time, the lower centre-section was built out to full aerofoil section and covered.
  All production machines from A.7101 onwards had the revised fuselage and covered lower centresection, and were given the new designation Bristol F.2B. The first 150 F.zBs (A.7101-A.7250) had the 190 h.p. Rolls-Royce Falcon I engine, with the exception of A.7177, in which the first installation of the 275 h.p. Rolls-Royce Falcon III engine was made. The second Bristol F.2B to have the Falcon III was A.7183, which was later fitted with the more powerful engine. The first few F.2Bs had no radiator shutters, but these were soon standardised. A further modification was the introduction of a new horizontal tail of reduced chord and increased span.
  Production continued with fifty machines (A.7251-A.7300) powered by the 220 h.p. Rolls-Royce Falcon II, and all subsequent Bristols, from B.1101 onwards, were intended to have the Falcon III. In 1917, however, Rolls-Royce engines were not being produced in sufficient quantities to meet the growing demands of the time. The realisation of the excellence of the Bristol Fighter led to a substantial expansion of production of the type, and by the autumn of 1917 it was obvious that Falcon production would not be able to keep pace with the output of Bristol Fighters.
  Alternative power units had to be considered, and the first choice was the 200 h.p. Hispano-Suiza. It was realised that this lower-powered engine would reduce the aircraft’s performance, so it was decided to use the Hispano Bristols as replacements for the R.E.8 and Armstrong Whitworth F.K.8 in the Corps Reconnaissance squadrons. The Falcon-powered machines were to be reserved for the fighter-reconnaissance squadrons, whose duties demanded the best possible performance.
  However, the 200 h.p. Hispano-Suiza was giving a great deal of trouble in 1917, as the pilots of the early S.E.5a’s knew only too well. Those engines made in France by the Brasier concern proved to be woefully defective, particularly in the hardening of the gears and airscrew shaft. Facilities for their overhaul in Britain became so over-taxed and the engine supply position so critical that many Brasier-built Hispano-Suizas were passed into service with the faulty gears.
  To have fitted appreciable numbers of Bristol Fighters with these Hispano-Suiza engines would have been to invite catastrophe, and the aircraft was modified to have the 200 h.p. Sunbeam Arab engine. The Arab was a liquid-cooled vee-eight of generally similar configuration to the Hispano-Suiza. The original Arab installation bore a strong external resemblance to that of the Wolseley Viper version of the S.E.5a, and was in fact an attempt to use S.E.5a radiators, which were readily available. The nose was flat and square with an arched top, and there was one radiator block for each group of cylinders. The top line of the engine cowling sloped down quite sharply to the top of the radiator, and it was felt that this resulted in the blast-tube for the Vickers gun being too short. The nose lines were therefore revised to give a horizontal top line to the cowling, and the end elevation of the nose resembled a rectangle surmounted by a shallow inverted V: the appearance was exceedingly ugly. An improvement was made by redesigning the nose so that it became straight-sided with rounded top and bottom; but at the last minute this was further modified to enable the cowling to accommodate either the Sunbeam Arab or the 300 h.p. Hispano-Suiza. Availability of the latter engine was promised in July, 1918.
  Mere modifications of the cowling were by no means the only worries connected with the Sunbeam Arab. The engine had given trouble from its earliest days. In the spring of 1917 several modifications had to be made to overcome weaknesses of the crank chamber and cylinders, and even then the Arab was so unsatisfactory that it was nearly shelved. After one engine had satisfactorily completed a test run of too hours on the bench, development proceeded; but many more modifications had to be made and specifications for materials had to be changed. As a result, the design of the engine was not settled until late in 1917: by the end of the year only eighty-one Arabs had been delivered against the production programme total of 1,800. The engine suffered severely from vibration at normal operating speeds, and even the introduction of specially-strengthened engine mountings in the Bristol Fighter airframe failed to achieve a fully satisfactory combination.
  The adoption of the Sunbeam Arab coincided with the extension of production of the Bristol Fighter to sub-contractors, and that engine was selected as the power unit of the machines ordered under the first two outside contracts, which were placed with the Gloucestershire Aircraft Co., Ltd., on October 30th, 1917, and with Marshall & Sons of Gainsborough on November 22nd, 1917. On the latter date, a contract was also given to the Cunard Steamship Co. for the construction of 500 Bristol Fighters with the 200 h.p. Hispano-Suiza engine; the factory which the Cunard company erected for the purpose at Aintree was taken over in February, 1918, by the Ministry of Munitions, and was thereafter known as National Aircraft Factory No. 3. Production did not begin at Aintree until March, 1918, and only 126 Bristol Fighter airframes were completed there.
  Further contracts for Arab-powered machines were let on February 22nd, 1918, with the Standard Motor Co., Armstrong Whitworth & Co., and Angus Sanderson & Co. These were followed on March 20th by a second contract for 150 machines from the Gloucestershire Aircraft Co., and on May 21st by a contract for too to be built by Harris & Sheldon.
  As stated above, it was intended to fit the 300 h.p. Hispano-Suiza engine to the Bristol Fighter; and with the promise of such engines in July, 1918, a batch of 350 Bristols were put in hand. Work on these machines had begun when it was found that all 300 h.p. Hispano-Suiza engines were wanted for the Martinsyde F.4 production programme.
Yet another change was made. This time the choice fell, almost with a suggestion of desperation, on the 230 h.p. Siddeley Puma six-cylinder in-line engine. The Bristol F.2B numbered B.1206 was tested with a Puma in February, 1918. At that time the installation bore a general resemblance to that of the Falcon, for the frontal radiator was retained. A large exhaust manifold was fitted on the port side, and the Vickers gun had to be mounted to starboard of the cylinders.
  The exhaust manifold and the gun obstructed the pilot’s forward view. The official test report suggested that the engine installation should be modified to be similar to that of the D.H.9, and that an underslung radiator or twin side radiators should replace the frontal surface.
  Most of the recommendations were implemented, and by September, 1918, the necessary modifications had been made to enable production Bristols to accommodate the Puma. In addition to the modifications to the cowling itself, the fuel tanks had to be completely redesigned and a massive exhaust manifold was fitted.
  The British & Colonial Aeroplane Co. fitted Pumas to the machines numbered E.3253 -E.3258 and H.1690-H.1707 at Filton, but none of these Bristols went further than the Aircraft Acceptance Park. Puma- powered Bristols were also built by the Gloucestershire concern and by the Austin Motor Co.
  In September, 1918, trials were carried out with the Bristol Fighter C.4654 powered by one of the high-compression Siddeley Pumas which developed 290 h.p. The installation of this more powerful engine was indistinguishable from that of the standard Puma. The improvement in performance was of little significance.
  In all these circumstances it is not surprising that the first deliveries of Bristol Fighters to Corps Reconnaissance units did not take place until September, 1918, whereas it had been planned to replace the R.E.8s from the previous April onwards. Five of the Corps squadrons in France had had one or two Bristols on their strength as early as March 21st, 1918: Squadrons Nos. 10 and 35 (Armstrong Whitworth F.K.8) and No. 16 (R.E.8) each had two, and Nos. 12 and 15 (R.E.8) each had one. But no Corps squadron ever was re-equipped with Bristol Fighters: the only units which used the Arab-powered version in France were the Long Range Artillery Flights L, M, N, O and P. L Flight was the first to join the B.E.F.: it arrived in France in July, 1918. Of the 721 Arab-Bristols on the charge of the R.A.F. on October 31st, 1918, only seventy-nine were with the Expeditionary Force in France.
  A few experimental Bristol Fighters had the 200 h.p. R.A.F. 4d engine. This was an air-cooled vee-twelve which did not lend itself to elegant cowling, and the installation was by no means beautiful.
  At least one Bristol Fighter, B.1200, was tested in October, 1918, with the 200 h.p. Wolseley Viper engine. Performance was poor, however, and no attempt was made to standardise the Viper.
  It was in its standard fighter-reconnaissance form with the Rolls-Royce Falcon engine that the Bristol Fighter won its undying fame. Once its great strength and manoeuvrability were realised and exploited by its pilots, it became one of the most effective weapons in the armoury of the R.F.C., and so far redressed the early losses of April, 1917, that by the time of the Armistice No. 48 Squadron had destroyed 148 enemy aircraft. The crews of No. 11 Squadron found that they could not bring the enemy to battle unless the Bristols flew in pairs or singly: enemy pilots would not attack if more than three of No. 11’s machines were flying together.
  In the summer of 1917, the Bristol Fighters of No. 48 Squadron escorted the D.H.4s of No. 5 (Naval) Squadron on many bombing raids; and twice during that year one of No. 48’s Bristols carried as its observer King Albert of Belgium, who wished to see the battlefield for himself.
  The Bristol Fighter gave excellent service throughout the Battles of Ypres, and in September, 1917, No. 48 Squadron began to fly at night to attempt to intercept the German bombers which attacked Dunkirk. This squadron had earlier scored a success against Gothas which were returning from a daylight raid on Harwich: on July 22nd, 1917, Captain B. E. Baker and his observer, Lieutenant G. R. Spencer, dived to the attack from 16,000 feet to 3,000 feet, and shot down one of the Gothas into the sea.
  The great German offensive of 1918 brought fresh tasks to the Bristol Fighter squadrons. Ground targets were plentiful, and No. 48 Squadron was in the thick of the ground attack work, whilst Nos. 11, 22 and 62 plied their craft at any altitude where there was fighting to be done.
  Eloquent testimony to the confidence that Bristol crews had in their machines was provided on May 7th, 1918, when two of No. 22 Squadron’s pilots attacked seven Fokkers over Arras. Four of the German fighters had fallen to the Bristols’ guns when fifteen more enemy fighters appeared. Only the exhaustion of their ammunition obliged the Bristol Fighters to break off the engagement, and by that time they had shot down four more Fokkers.
  In Italy, No. 139 Squadron’s Bristols distinguished themselves against odds: on August 8th, 1918, four machines of that unit beat off an onslaught by twenty enemy fighters. No. 139 Squadron began its career as a Flight of Bristol Fighters which was sent to Italy in the spring of 1918 in compensation for the transfer to the Western Front of No. 42 (R.E.8) Squadron on March 14th, 1918. This Flight of Bristols was at first attached to No. 28 Squadron, but it was soon transferred to No. 34 Squadron and named “Z” Flight. A second Bristol Flight arrived in June, and the two were named No. 139 Squadron on July 3rd, 1918.
  Farther east, in Palestine, Bristol Fighters gave the R.F.C. their first real opportunity of carrying the war to the enemy in the autumn of 1917, when a few were sent there. Five Bristols were serviceable on October 7th, and on that day the first offensive patrol was made. On the next day, the first German fighter to be captured on the Sinai-Palestine front was brought down in the British lines. By October 27th, 1917, No. 111 Squadron had six Bristol Fighters on its strength; these machines were handed over to No. 67 (Australian) Squadron, R.F.C., in January, 1918, when that unit was re-equipped. No. 67 Squadron became No. 1 Squadron, Australian Flying Corps, on February 6th, 1918. The only other Bristol Fighter which saw operational service in the Middle East was the solitary example which was used by “X” Flight at El Gueira from mid-August until September 15th, 1918.
  The Bristols of No. 1 Squadron, A.F.C., did much to ensure the success of General Allenby’s offensive of September, 1918: their discharge of their duties earned them this tribute in The War in the Air (Vol. VI, page 207) “...it would hardly be an exaggeration to say that the Bristol Fighters of the Australians kept the sky clear.” These same machines exacted a dreadful toll of the retreating Turkish Seventh Army on September 21st, 1918. Trapped in the Wadi el Far‘a, the Turks were systematically slaughtered in a daylong attack with bombs and machine-gun fire. In this grim work the Australians were helped by the S.E. ja’s of Nos. in and 145 Squadrons, and by the D.H.gs of No. 144 Squadron. Two Bristol Fighters of No. 1 Squadron, A.F.C., also gave material assistance to Colonel T. E. Lawrence and his Arab irregulars.
  It was inevitable that an aeroplane which had given such convincing proof of its fighting ability should be selected for Home Defence duties. The choice was hastened by the beginning of the night raids on London in September, 1917. The intention was that nine squadrons of the 6th Brigade were to be equipped with the Bristol Fighter: these were Squadrons Nos. 33, 36, 38, 39, 51, 75, 76, 77 and 141. Only Nos. 36, 39 and 141 were fully equipped with the type, and Nos. 33 and 76 had a few.
  Some of the Home Defence Bristol Fighters had an unusual system of gun sighting. The observer’s Lewis gun was sighted by the pilot by means of a special sight mounted on the centre-section and inclined upwards and forwards at an angle of 45 degrees. The observer aligned his gun parallel to the sight, the pilot manoeuvred the aircraft until he had lined up the sights on the target, whereupon he signalled to the observer, who opened fire.
  Just before the advent of the Bristol F.2A, Sergeant A. E. Hutton of No. 39 Squadron had invented a special illuminated gun-sight for use at night. The Hutton sight was in use from March, 1917, until the following December, when it was superseded by the Neame sight, which was illuminated in similar fashion to the Hutton Sight.
  The night-flying Bristols accounted for two of the thirty-eight Gothas which, in company with three Zeppelin Giants and two single-engined machines, made the last aeroplane attack on London on the night of May 19th/20th, 1918. Fourteen of the eighty-four Home Defence aircraft which took off to attack the German force were Bristol Fighters. Lieutenant E. E. Turner and Air Mechanic H. B. Barwise of No. 141 Squadron attacked a Gotha which had survived the attack of Major F. Sowrey of No. 143 (Camel) Squadron. The Gotha pilot had been wounded by Major Sowrey, and the further damage inflicted by the Bristol forced the German machine down. It tried to land at Harrietsham aerodrome but crashed.
  Lieutenant A. J. Arkell and Air Mechanic A. T. C. Stagg of No. 39 Squadron destroyed another Gotha which had survived the attacks of a Camel of No. 78 Squadron. They attacked the German machine from underneath and fought it down from 10,000 feet to 1,500 feet, when it burst into flames and crashed at Roman Road, East Ham.
  The Bristol Fighter shared with the S.E.5a a certain disadvantage for night work: both machines had stationary water-cooled engines which took longer to warm up than the contemporary rotary motors, and both had long noses which made them comparatively difficult to land at night on small aerodromes. At the time of the Armistice at least one mixed squadron of Bristol Fighters and Sopwith Pups was due to be re-equipped with the single-seat fighter version of the Avro 504K.
  The United States of America entered the war on April 6th, 1917, and set about the production of aircraft on a characteristically ambitious scale. The initial “Procurement Program” planned for the immediate acquisition of 7,375 aircraft, and the ultimate aim was the production of no fewer than 20,475 machines in twelve months. A substantial number of these aircraft were of British design. Towards the end of 1917 it was arranged that the Bristol Fighter would be produced by the Curtiss Aeroplane and Motor Corporation, and 2,000 were ordered. Two Bristol-built airframes were sent as samples to the Curtiss works.
  The Curtiss-built machines were to have had the 300 h.p. Wright-built Hispano-Suiza engine, but political pressure was brought to bear in favour of the American Liberty 12, which was substituted for the Wright-Hispano. This was done in defiance of the strenuous opposition of the British & Colonial Aeroplane Co., for Captain Barnwell knew that the Liberty was too bulky and too heavy for the aeroplane.
  Responsibility for the engineering behind the production of the Liberty-powered Bristol Fighter rested with the U.S. Government until the production programme was well advanced. Even when the Government relinquished that responsibility, the Curtiss company were not allowed to make changes of any magnitude. At an early stage, Curtiss engineers realised that Barnwell was correct in thinking that the installation of the Liberty engine in the Bristol Fighter would not be satisfactory; they therefore began to design a completely new aircraft (the Curtiss CB) to use the Liberty and to perform the same duties as the Bristol.
  The installation of the Liberty engine in the Bristol Fighter was clumsy; the radiators were badly placed; and the aeroplane was nose-heavy and thoroughly unpleasant to fly. The first machine was completed in March, 1918, and was delivered to the U.S. Air Service during the following month. Twenty seven were built before production was halted and the remainder of the contract cancelled. Blind to their own blunder in fitting the Liberty to an aeroplane unsuited to the engine, the U.S. Army shifted the blame on to the innocent aircraft and condemned the Bristol Fighter as dangerous.
  Another version of the design was, however, ordered in large quantities in America. The Engineering Division of the Bureau of Aircraft Production undertook the fairly extensive re-design of the Bristol Fighter and evolved two designs, both for aircraft which had completely re-designed structures: one version was powered by the 300 h.p. Hispano-Suiza, and was designated USB-1; the other was designed for the 290 h.p. Liberty 8, and was designated USB-2. An optimistic order for 2,000 machines of the USB type was placed.
  These aircraft had veneer-covered fuselages of faired contours, and the area of their vertical tail assembly was increased. Many other detail modifications were made, and the equipment of the machines was different from that of the standard British-made Bristol F.2B.
  Some standard Bristol Fighter airframes had been sent to America for experimental purposes. One was fitted with a 300 h.p. Hispano-Suiza, and had the McCook Field Project No. P.30; a second had one of the first eight-cylinder Liberty 8 engines of 290 h.p., and the Project No. P.37. The latter Bristol crashed before performance tests were carried out. These two Bristol Fighters have been referred to as the USB-1 and USB-2 respectively, but that is incorrect. In the summer of 1918, the construction of twelve Bristol Fighters was begun at McCook Field. The intention was to build eight machines to the basic Bristol design, four with Hispano-Suiza engines and four with the new and re-designed Liberty 8; and the remaining four were to be structurally similar but with veneer-covered fuselages, two having Hispano-Suizas and two Liberty 8s. Work lagged badly, however, and the construction of the first eight aircraft was finally stopped in September, 1918.
  Work was still proceeding on the design of the USB-1 and USB-2, which were re-designated USXB-1 and USXB-2 at about this time. A number of fuselages of slightly different design were tested statically, and construction of two prototypes was begun.
  The four Bristol F.2Bs with veneer-covered fuselages were still in hand, but in October, 1918, the construction programme was altered to consist of only two USXB-1s and two USXB-2s. This plan was retained until the Liberty 8 engine was abandoned in 1919, whereupon the USXB-2s were modified to take the 300 h.p. Hispano-Suiza, and all four machines emerged in July, 1919, under the designation Engineering Division XB-1A.
  The order for 2,000 aircraft of USB type was cancelled at the time of the Armistice, but during 1920 and 1921 forty XB-1As were built by the Dayton-Wright concern. These production machines had the 330 h.p. Wright H engine, and their all-up weight was about 800 lb greater than that of the original XB-1A. In 1921, one of the production XB-1As was fitted with the 350 h.p. Packard 1A-1237 engine; and another (A.S.64156) was used as a test-bed for the Curtiss D-12.
  The Bristol Fighter remained in service with the Royal Air Force for many years after the Armistice: in fact, it was not retired until 1932. In the post-war years the Bristol was used on Army Cooperation duties by nine Service squadrons, and did yeoman service on the North-West Frontier of India and in Iraq.
  Production for the R.A.F. continued until 1926, and the type was used in a large number of experiments with wings of varying aspect ratio, different aerofoil sections, control surfaces, evaporative cooling systems, and Handley Page slots. This last device prolonged the Bristol’s service life by a few years, and the ultimate Service version had slots, long-travel undercarriage, and a balanced rudder.
  Other nations were quick to adopt the type for their air services, and the post-war years saw considerable numbers of variously-powered Bristol Fighters bound for destinations in Spain, Belgium, Mexico, Norway, Sweden, Greece, Bulgaria, and the Irish Free State.
  A substantial number of Bristol Fighters were given registrations on the British Civil Register; many were shipped abroad, however. The Bristol company produced a number of passenger-carrying conversions, and development continued for many years and in many forms.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Other Contractors: Sir W. G. Armstrong, Whitworth & Co., Ltd., Gosforth, Newcastle-on-Tyne. The Gloucestershire Aircraft Co., Ltd., Cheltenham. Harris & Sheldon, Ltd., Stafford Street, Birmingham. Marshall & Sons, Gainsborough. National Aircraft Factory No. 3, Aintree, near Liverpool. Angus Sanderson & Co., Newcastle-on-Tyne. The Standard Motor Co., Ltd., Coventry. The Austin Motor Co. (1914), Ltd., Northfield, Birmingham. The Curtiss Aeroplane Co., Buffalo, New York, U.S.A.
  Power: 190 h.p. Rolls-Royce Falcon I. 150 h.p. Hispano-Suiza (second prototype F.2A only). 220 h.p. Rolls-Royce Falcon II. 275 h.p. Rolls-Royce Falcon III. 200 h.p. Sunbeam Arab. 200 h.p. Hispano-Suiza. 230 h.p. Siddeley Puma. 290 h.p. Siddeley Puma (high compression). 300 h.p. Hispano-Suiza. 200 h.p. R.A.F. 4d. 200 h.p. Wolseley W.4a Viper. 290 h.p. Liberty 8. 400 h.p. Liberty 12.
  Dimensions: Span: F.2A prototypes 39 ft 2 1/2 in.; production F.2A and standard F.2B 39 ft 3 in. Length: F.2A (A.3303) 25 ft 9 in.; F.2A (A.3304) 24 ft 10 in.; F.2B (Falcon) 25 ft 10 in.; (200 h.p. Hispano-Suiza) 24 ft 8 1/2 in.; (Arab) 24 ft 10 in.; (230 h.p. Puma) 26 ft; (Viper) 24 ft 9 in.; (Liberty 12) 27 ft 1 in.; (Liberty and Wright H) 25 ft 5 in. Height: (A.3303) 9 ft 4 in.; (A.3304) 9 ft 6 in. F.2B: (Falcon I) 9 ft 4 in.; (Falcon II and HI) 9 ft 9 in.; (200 h.p. Hispano and Viper) 9 ft 6 in.; (Arab and 230 h.p. Puma) 9 ft 5 in. Chord: 5 ft 6in. Gap: 5 ft 4 1/2 in. Stagger: production F.2A 17-1 in.; F.2B (Falcon I) 16-9 in.; (Falcon III) 18-1 in.; (200 h.p. Hispano) 19-7 in. Dihedral: 3° 30'. Incidence: (Falcon) 1°45'; (200 h.p. Hispano) 1°42' at centre-section, 1° 24' at inner struts, 1° at outer struts. Span of tail: F.2A 12 ft; F.2B 12 ft 10 in. Wheel track: 5 ft 5 1/4 in. Tyres: 750 X 125 mm. Airscrew diameter: A.3303, four-blader, 9 ft 2 1/2 in.; two-blader, 9 ft 9 in.; A.3304, 8 ft 10-3 in. Falcon II and III, four-blader, 9 ft 4 m.; two-blader, 9 ft 8 in.; 200 h.p. Hispano, 9 ft 4 in.; 230 h.p. Puma, 9 ft 6 in.; Viper, 8 ft 4I in.; 300 h.p. Hispano, 9 ft.
  Areas: Wings: F.2A 389 sq ft; F.2B 405-6 sq ft. Ailerons: each 13 sq ft, total 52 sq ft. Tailplane: 22-25 sq ft. Elevators: 23-25 sq ft. Fin: upper 6-9 sq ft, lower 3-8 sq ft, total 10-7 sq ft. Rudder: 7-2 sq ft.

Tankage (in gallons):
Petrol
   Main Tank Gravity Tank Rear Tank Total Oil Water
F.2A, A.3303 31 - 19 50 4 9
F.2A, A.3304 40 - 14 54 3 1/4 6
F.2B, Falcon III - - - 45 4 6 1/2
F.2B, 200 h.p. Hispano-Suiza 27 - 18 45 3 1/2 9 1/2
F.2B, Arab 26 1/2 4 1/2 14 45 4 1/2 -
F.2B, 230 h.p. Puma 26 - 18 44 2 3/4 -
F.2B, 290 h.p. Puma - - - 38 7 -
F.2B, Viper - - - 48 3/4 4 1/2 8 1/2
F.2B, 300 h.p. Hispano-Suiza - - - 51 4 1/2 -

  Armament: One fixed Vickers machine-gun mounted centrally under the cowling, and synchronised by Constantinesco gear to fire forward through the revolving airscrew. One or twin double-yoked Lewis machineguns on Scarff ring-mounting on the rear cockpit. Up to twelve 20-lb Cooper fragmentation bombs could be carried on racks under the lower wings.

Bristol M.1A, M.1B and M.1C

  CAPTAIN BARNWELL was quick to realise the value of speed and manoeuvrability in single-seat fighters, and in July, 1916, he designed an aeroplane of that type which was distinguished by remarkably clean design and high performance on a mere 110 h.p.
  By choosing a monoplane configuration he took a bold step, not merely against the convention of the biplane form, but also in defiance of the prejudice against monoplanes which had lingered in Britain since the hasty and ill-advised “monoplane ban” of 1912.
  The aeroplane he designed was as clean as contemporary constructional methods would permit. The basis of the design was the engine installation, and Barnwell had satisfied himself about its efficiency by using the Bristol Scout C No. 5555 as a flying test-bed. This Scout was fitted with a 110 h.p. Clerget rotary motor, and its airscrew bore a large spinner to provide reasonably clean aerodynamic entry.
  There was nothing radical about the construction of the monoplane. The basic structure of the fuselage was a typical wooden box-girder, cross-braced by wires; it was faired by means of wooden formers and stringers to continue the circular cross-section of the engine installation almost down to the sternpost. The wings were attached to the upper longerons and were braced by cables. The duplicated flying wires were attached at their inboard ends to the lower longerons, and the landing wires ran up to a cabane which, on the prototype, consisted of two roughly semicircular half-hoops of steel tubing.
  The first machine was designated M.1A, and was allotted the serial number A.5138. Design and construction work were carried out so expeditiously that the M.1A was first tested by F. P. Raynham in September, 1916, when it amply fulfilled its designer’s expectations by returning a maximum speed of 132 m.p.h. The M.1A had no armament.
  Four more prototypes were built for Service trials. These machines were designated M.1B, and differed from the M.1A in having a pyramidal cabane composed of four straight steel tubes; a Vickers gun was mounted on the port upper longeron just in front of the cockpit; a cut-out was made in the starboard wing root between the spars, in order to improve downward vision; and provision was made for the fitting of the 110 h.p. Le Rhone engine as an alternative to the Clerget. One of the M.1Bs was fitted with the 150 h.p. A.R.1 engine, and was tested in March, 1917.
  Rumours of the Bristol monoplane’s speed and manoeuvrability soon reached the R.F.C. in France, and its introduction as a standard fighter was eagerly awaited. But as time went on, no Bristol monoplanes reached the squadrons in France, and after a time it became known that the type had been rejected for operations on the Western Front. The official reason for its rejection was that its landing speed was too high at 49 m.p.h. It was said, however, that this reason was adduced to conceal the lack of skill of a certain senior officer who misjudged his landing on one of the prototypes and crashed.
  Be that as it may, the production contract called for only 125 machines, and those which saw operational service were relegated to the Middle East.
  The production aircraft were designated M.1C. They were powered by the 110 h.p. Le Rhone engine, and the spinner had a larger central aperture. The Vickers gun was moved to a central position on top of the fuselage, and there were clear-view cut-outs in both wing roots. One machine did go to France in 1917, but the only operational M.1Cs were drawn from the thirty-five which were sent to the Middle East. Even there the type did not form the complete equipment of any squadron.
  The first Bristol monoplanes to be sent into the field were those which were sent to Palestine in June, 1917. There they formed part of the heterogeneous collection of aircraft with which No. 111 Squadron was equipped. Their presence did something towards curbing the reconnaissance activities of the enemy, but their rather short flight endurance precluded their use on escort duties.
  In the Mesopotamian theatre of war, No. 72 Squadron arrived at Basra on March 2nd, 1918, equipped with Bristol M.1Cs, S.E.5a’s, D.H.4s, Spads and Martinsyde Elephants. The Bristol monoplanes were used by “C” Flight of the squadron: this Flight was attached to the III Corps, and operated from Mirjana. The first noteworthy achievement by “C” Flight was one which is probably unique in the annals of aerial warfare: two of the pilots, flying Bristol M.1Cs, so impressed some Kurdish tribesmen with a hair-raising display of aerobatics that the entire tribe came over to the British side.
  In May, 1918, Bristol M.1Cs of No. 72 Squadron played an important part in the capture from the Turks of the towns of Kifri and Kirkuk. During the few days immediately preceding these successes the Bristols strafed troop concentrations, drove off the few enemy aircraft which put in an appearance and, in one particularly fine effort, silenced an anti-aircraft gun in a low-flying attack. Later, in October, 1918, while cooperating with Brigadier-General A. C. Lewin’s force in Kurdistan, the machines of “C” Flight did much valuable work against ground targets: on one occasion they attacked a Turkish long-range gun from a height of 200 feet and put it out of action.
  In Macedonia, a few Bristol M.1Cs were added to the strength of Squadrons Nos. 17 and 47 in January, 1918. These machines were transferred to No. 150 Squadron on April 26th, 1918, when that unit was formed by combining two flights, one taken from No. 17 Squadron, the other from No. 47. These Bristols were few in number. One of them was shot down into Lake Dojran on September 3rd, and at the Armistice No. 150 Squadron had only one Bristol monoplane on its strength.
  In 1917 six Bristol M.1Cs were sent to Chile by the British Government in part payment for two battleships which had been building for Chile in British yards at the outbreak of war but had been taken over by the Royal Navy. These six had a chequered career. They were some of a batch of twelve which had been stored behind the Royal Enclosure at Ascot, and at one time orders were issued for the removal of serviceable equipment and the subsequent scrapping of the airframes. These orders were cancelled when demands came through from Marske and Montrose, each for six machines. The Bristols were sent there but were soon returned to Ascot, whence six went to Chile.
  One of these Bristol monoplanes, flown by Lieutenant Godoy of the Chilean Air Force, distinguished itself by making the first air crossing of the Andes on December 12th, 1918. The route flown was from Santiago de Chile to Mendoza, Argentina, and back; part of the flight was made at 20,000 feet. Godoy’s feat was repeated on April 4th, 1919, by Lieutenant Cortinez, who also flew a Bristol M.1C.
  After the Armistice, four M.1Cs were bought back by the British & Colonial Aeroplane Co. One was sold to Spain; and another, which was registered G-EAVP, was fitted with a 100 h.p. Bristol Lucifer three-cylinder radial engine and took part in several air races. This machine was re-designated M.1D.
  An M.1C found its way to Australia soon after the war, and made various exhibition flights there in the summer of 1919. This aircraft survived until the middle 1930s, when it was still flying, though in an extensively modified form and powered by a D.H. Gipsy engine. Its registration was VH-UQI.
  The failure to build the Bristol M.1C in large quantities for the squadrons in France has always been regarded as one of the major blunders of the 1914-18 war. Those pilots who flew the type were full of praise for its delightful handling qualities, and the view from its cockpit in all vital directions was unsurpassed by any contemporary fighter. It could not have failed to be popular with the pilots of its day, nor to have had a considerable influence on the war in the air.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Power: M.1A: 110 h.p. Clerget. M.1B: 110 h.p. Clerget, 150h.p. A.R.1. M.1C: 110 h.p. Le Rhone.
  Dimensions: Span: 30 ft 9 in. Length: M.1A 20 ft 3 in., M.1B, with A.R.1 engine, 20 ft 8 in., M.1C 20 ft 5 1/2 in. Height: M.1B, with A.R.1, 7 ft 7 in., M.1C 7 ft 9 1/2 in. Chord: 5 ft 11 in. Dihedral: 2°. Incidence: 0°. Span of tail: 10 ft 3 in. Airscrew diameter: 8 ft 6 1/2 in. Wheel track: 4 ft 7 in. Tyres: 700 X 75 mm.
  Areas: Wings: 145 sq ft. Ailerons: each 9 sq ft, total 18 sq ft. Tailplane: 20 sq ft. Elevators: 15 sq ft. Fin: 5 sq ft. Rudder: 4-5 sq ft.
  Armament: One fixed forward-firing Vickers machine-gun, synchronised to fire through the revolving airscrew by Constantinesco C.C. Gear Type B. On the M.1B the gun was mounted on the port upper longeron; on the M.1C it was mounted centrally on top of the fuselage.

Weights (lb) and Performance:
M.1A M.1B (with A.R.i engine) M.1C
No. of Trial Report M.2I M.87 M.161
Date of Trial Report July, 1916 March, 1917 December, 1917
Type of airscrew used on trial P-3017 - P.3017
Weight empty 913 930 896
Military load 50 80 80
Pilot 180 180 180
Fuel and oil 183 180 192
Weight loaded 1,326 1,370 1,348
Maximum speed (m.p.h.) at
ground level - - 130
5,000 ft - - 127
5,400 ft 128 - -
6,500 ft 127 115-5 -
7,300 ft 125-5 - -
9,300 ft 120 - -
10,000 ft 118 110 111-5
I 1,200 ft 115-5 - -
13,100 ft 112-5 - -
15,000 ft 110-5 100 104
m. s. m. s. m. s.
Climb to
1,000 ft 0 35 - - 0 40
2,000 ft 1 10 - - - -
3,000 ft 1 55 - - - -
4,000 ft 2 40 - - - -
5,000 ft 3 25 - - - -
6,000 ft 4 25 - - 5 10
6,500 ft 4 5° 5 50 - -
7,000 ft 5 "5 - - - -
8,000 ft 6 20 - - - -
9,000 ft 7 20 - - - -
10,000 ft 8 30 11 05 10 25
I 1,000 ft 9 50 - - - -
12,000 ft I I 10 - - - -
13,000 ft !2 55 - - 15 55
14,000 ft 14 55 - - - -
15,000 ft 17 25 27 40 19 50
15,600 ft 19 40 - - - -
16,000 ft - - - - 23 35
18,000 ft - - - - 30 55
20,000 ft - - - - 41 35
Service ceiling (feet) 17,000 15,000 20,000
Endurance 2 hours 55 minutes 1 3/4 hours 1 3/4 hours
Tankage (gallons': Petrol 17-5 - 18
Oil 5-5 - 5

  Service Use: Mesopotamia: No. 72 Squadron, “G” Flight only. Palestine: No. 111 Squadron, part only. Macedonia: a few Bristol M.1Gs were used by R.F.C. Squadrons Nos. 17, 47 and 150. Training: flown at Stonehenge, Marske, Montrose and Hounslow.
  Production and Allocation: One Bristol M.1A, four M.1Bs, and 125 M.1Cs were built. Official statistics state that only seventy-eight were actually delivered to the R.F.C.: one went to France, thirty-five to the Middle East, and forty-two to training units. On October 31st, 1918, the R.A.F. had forty-seven on charge, of which thirteen were in Mesopotamia, two in Macedonia and one in Palestine; twenty-six were with training units, and five were at various aerodromes in Britain.
  Serial Numbers: M.1A: A.5138; M.1B: A.5139-A.5142 (M.1A and M.1Bs were built under Contract No. 87/A/761). M.1C: C.4901-C.5025 (built under Contract No. A.S.8236).
  Notes: C.4902 had 110 h.p. Le Rhone engine No. 101149 W.D. 15867. At Martlesham Heath in November, 1917, holes of 2 mm diameter were drilled in the engine’s induction pipes; this reduced speed to 106 m.p.h. at 10,000 ft. C.4965 was flown at Hounslow.
  Costs:
   Airframe, without engine, instruments and gun £770 0s.
   110 h.p. Le Rhone engine £771 10s.

Bristol S.2A

  THE lack of a British synchronising gear for machine-guns resulted in the appearance of some peculiar aeroplanes in the early stages of the war. Usually the compromise which had to be adopted in order to provide reasonably effective armament had a catastrophic effect upon performance.
  The Bristol S.2A was a reasoned attempt to produce a two-seat scouting aeroplane with the speed of a single-seater but capable of defending itself while yet remaining under the full control of its pilot. The aeroplane was a small side-by-side two-seater biplane; the passenger was responsible for firing the defensive armament.
  The machine was a development of the Scout D. In fact, it had the same wings and tail-unit as the single-seater. The fuselage was wide enough to accommodate the two occupants side-by-side, and the centre-section was correspondingly wider than that of the Scout D. The engine was the 110 h.p. Clerget, which proved to be somewhat troublesome.
  Two prototypes were built in May and June, 1916, and the type proved to be quite fast and manoeuvrable under test. Production was not undertaken, for interrupter gears had meanwhile become available.
  One of the S.2As was later used at Gosport, where it was fitted with a 100 h.p. Gnome Monosoupape and was flown with a modified engine cowling. There was no cowling below the level of the airscrew shaft, and three large apertures were cut in the upper portion.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Power: 110 h.p. Clerget; 100 h.p. Gnome Monosoupape.
  Dimensions: Span: 28 ft 2 in. Length: 21 ft 3 in. Height: 10 ft. Chord: 4 ft 6 in. Span of tail: 10 ft.
  Weights: Loaded: 1,400 lb.
  Performance: Maximum speed: 95 m.p.h.
  Production: Two prototypes were built under Contract No. 87/A/372.
  Serial Numbers: 7836-7837.

Bristol T.T.A

  SOON after the outbreak of war, it was realised that aerial combat was not only a possibility but an accomplished fact; and ways had to be sought to provide aircraft combining performance with effective fire power.
  In September, 1915, Frank Barnwell, assisted by L. G. Frise, began work on the design of a twin-engined two-seat fighter which was designated Bristol T.T., or Twin Tractor. Two engines were considered necessary to achieve a worthwhile performance, and the original design was for two 150 h.p. R.A.F. 4a engines. The gunner had two free Lewis guns, and occupied the nose cockpit from which he had a wide field of fire. The pilot sat behind the wings, and a single Lewis gun firing aft was provided for his use. Dual control was provided. The tail unit was generally similar in appearance to that of the Bristol Scout, and there were enormous ailerons.
  Petrol was carried in three main tanks in the fuselage, and pressure feed to the engines was maintained by a fan-driven pump. Two further tanks were fitted, one behind each engine. These were intended to be gravity tanks but were converted to pressure tanks.
  By the time the T.T. was ready for construction the output of R.A.F. 4a engines had been earmarked for B.E.12s. The Bristol design was therefore modified to have two Beardmore engines of either 120 h.p. or 160 h.p. Only the lower-powered engines became available, however, and the completed aircraft, re-designated T.T.A., was tested in May, 1916, by Captain Hooper, R.F.C. The engines turned in opposite senses.
  Later in May the T.T.A. went to Upavon to undergo official trials. Because it was underpowered its performance was not good; and it was adversely criticised on several grounds, but principally on the poor outlook from the pilot’s cockpit and the impossibility of fitting rearwards-firing guns. There was no kind of intercommunication between pilot and gunner; and the fuel system and poor lateral control were the subjects of adverse criticism.
  By the time the T.T.A. had flown, interrupter gears had become available, and Captain Barnwell was already looking ahead to the design which was to develop into the Bristol Fighter. There were therefore no misgivings over the abandonment of the T.T.A.
  The projected Bristol F.3A incorporated the wings, tailplane and rear fuselage of the T.T.A. The F.3A was designed to the same specification as the Armstrong Whitworth F.K.12, Sopwith LRTTr and Vickers F.B.11; and, like them, it was to have had the 250 h.p. Rolls-Royce engine. Two gunners were to have been accommodated in two cockpits mounted on the upper wing.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: Two 120 h.p. Beardmore. Engines Nos. 2713F (starboard) and 3239F (port).
  Dimensions: Span.: 53 ft 6 in. Length: 39 ft 2 in. Height: 12 ft 6 in. Chord: 8 ft. Gap: 7 ft 10 1/2 in. Stagger: 11-8 in. Dihedral: 4°. Incidence: 2°. Span of tail: 17 ft 8 in. Airscrew diameter: 8 ft 11 in.
  Areas: Wings: 817 sqft. Tailplane: 81 sq ft. Elevators: 47 sq ft. Rudder: 33 sq ft.
  Weights and Performance: No. of Trial Report: M.37. Date of Trials: May 23rd and 24th, 1916. Place of trials: Central Flying School, Upavon. Airscrews used on trial: Type No. P.2359; maker’s series numbers B. & C. 2495 and 2498.
  Weight empty: 3,820 lb. Military load: 100 lb. Crew: 320 lb. Fuel and oil: 860 lb. Weight loaded: 5,100 lb. Maximum speed at ground level: 86-7 m.p.h.; at 2,000 ft: 85-8 m.p.h.; at 4,000 ft: 85-3 m.p.h.; at 6,000 ft: 85-6 m.p.h.; at 8,000 ft: 85 m.p.h. Climb to 1,000 ft: 3 min; to 2,000 ft: 6 min 45 sec; to 3,000 ft: 10 min 8 sec; to 4,000 ft: 13 min 30 sec; to 5,000 ft: 17 min 15 sec; to 6,000 ft: 21 min; to 7,000 ft: 25 min 52 sec; to 8,000 ft: 32 min 15 sec; to 9,000 ft: 39 min 45 sec; to 10,000 ft: 53 min 15 sec. Service ceiling: 9,500 ft.
  Tankage: Petrol: three main pressure tanks 93 gallons; two service pressure tanks 11 gallons each; total 115 gallons. Oil: 9 gallons. Water: 10 gallons.
  Armament: Two free Lewis machine-guns. One was fired by the gunner in the nose cockpit, the other by the pilot.
  Production: Two prototypes were built under Contract No. 87/A/330.
  Serial Numbers: 7750-7751.

Bristol M.R.1

  WHILE the prototypes of the Bristol F.2A were still under construction, the British & Colonial Aeroplane Co. were asked to design a similar machine of all-metal construction, with a particular view to operations in or near the tropics where that form of construction would have considerable advantages over the conventional wire-braced wooden structures of the time.
  The preliminary general layout was sketched by Frank Barnwell in July, 1916, but the development of the design was carried out by W. T. Reid. The completed design was known as the Bristol M.R.1.
  In a general way, the M.R.1 resembled the F.2A: the fuselage was mounted midway in the gap between the wings; the lower centre-section was an open cross-braced structure; and the crew were accommodated close together. The fabric-covered wings were of orthodox appearance, but were of all-steel construction and were built by the Steel Wing Co. of Cheltenham. However, the first machine (A.5177) was delivered with wooden wings.
  The fuselage was built in four sections, bolted together, but the basic structure was a wire-braced box girder made of steel tubing. The fuselage was covered with aluminium sheet which was strengthened locally by corrugated sheet aluminium riveted to the inside. This method of construction produced a smooth outer covering, but no attempt was made to work double curvature of the skin and, as a result, the M.R.1 had rather more severe lines than the F.2A. Interplane and undercarriage struts were of steel tubing.
  Two prototypes were built, and were powered by the 150 h.p. Hispano-Suiza engine. Captain Barnwell flew the first a good deal for experimental purposes, and ultimately crashed it by flying it into a tree. The second machine (A.5178) was sent to the Aeronautical Inspection Directorate at Kingsway, and thereafter underwent static tests. This machine latterly bore the number A.58623 on its fuselage: this was not a genuine serial number, and the aeroplane was not flown with it.
  At one time it was intended to fit the M.R.1 with wings built on the Mayrow principle, which embodied components of aluminium alloy, but it is uncertain whether this was ever done. A pair of Mayrow wings were made and were submitted for structural test, however.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Brislington, Bristol.
  Power: 150 h.p. Hispano-Suiza. Engine No. W.D.10109 was fitted to the first M.R.1, A.5177.
  Dimensions: Span: 42 ft 2 in. Length: 27 ft. Height: 10 ft 3 in. Chord: 6 ft. Gap: 5 ft 11 in. Stagger: nil. Dihedral: 3° 30'. Incidence: 0°. Span of tail: 16 ft 3 in. Airscrew diameter: 8 ft 10 in.
  Areas: Wings: upper 235 sq ft, lower 223 sq ft, total 458 sq ft. Ailerons: each 14-75 sq ft, total 59 sq ft. Tailplane: 27-8 sq ft. Elevators: 30 sq ft. Fin: 7-8 sq ft. Rudder: 8-25 sq ft.
  Weights: Empty: 1,700 lb. Military load: 270 lb. Crew: 360 lb. Fuel and oil: 480 lb. Weight loaded: 2,810 lb.
  Performance: Maximum speed at ground level: 110 m.p.h.; at 5,000 ft: 106 m.p.h.; at 10,000 ft: 98 m.p.h.
Climb to 5,000 ft: 8 min; to 10,000 ft: 20 min.
  Tankage: Petrol: 50 gallons. Oil: 5 gallons.
  Armament: One fixed Vickers machine-gun mounted centrally in a tunnel under the cowling, and synchronised to fire forward through the revolving airscrew; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Production: Two prototypes were built under Contract No. 87/A/865.
  Serial Numbers: A.5177-A.5178. The latter aircraft bore the number A.58623 at a later stage.

Bristol Braemar

  CAPTAIN BARNWELL made his preliminary designs for a large triplane bomber as early as November, 1917, when it was made known that bombing attacks on Berlin were to be carried out from bases in England as soon as aircraft were available which were capable of doing so.
  The original conception was of a large triplane with a fuselage of good aerodynamic form incorporating a central engine room in which four engines were to be installed. Two outboard tractor airscrews were to be driven by shafts and gearing. Internal stowage for six 250-lb bombs was envisaged, and petrol for a range of at least 1,000 miles was to be carried.
  Development of the design was entrusted to W. T. Reid, for Barnwell wished to devote his attention to the two-seat fighter which was to become the Badger. The bomber design was progressively modified, and was considerably different from Barnwell’s original layout by the time a contract for three prototypes was awarded.
  The machine as built was named Braemar, and in order to test the airframe without delay the first prototype was fitted with four 230 h.p. Siddeley Puma engines mounted on the centre mainplane in two back-to-back pairs. The basic structure was of wood with the usual wire bracing. The fuselage was covered with plywood, and not the least remarkable feature of the Braemar was the fact that the wings could be folded. It was much larger than any other aeroplane built at Filton up to that date: its dimensions prevented the assembly of more than one machine at a time. The final assembly had to be carried out in a hangar at the aerodrome, and the first Braemar was completed during the summer of 1918. The test flying was done by F. P. Raynham, and the machine underwent official trials at Martlesham Heath in September, 1918. The official report mentions a certain amount of vibration in the fuselage, and modifications were made to the undercarriage. The second Braemar, C.4297, had the improved undercarriage.
  The second machine was powered by four Liberty 12 engines, and was designated Braemar Mk. II. It did not fly until February 18th, 1919, and arrived too late to be ordered in quantity. Its performance was good, and it might well have proved to be an efficient bomber if the war had lasted longer.
  The Braemar Mk. II was at Martlesham Heath in July, 1919, and apparently remained there until the following year. On test, its fuel system proved to suffer from a defect similar to that of the D.H.10: at low air speeds the wind-driven pumps failed to maintain an adequate supply of fuel.
  The third airframe was not completed as a Braemar but, with a completely re-designed fuselage, emerged in 1920 as the Bristol Pullman, a commercial machine which provided enclosed accommodation for fourteen passengers in considerable luxury.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: Braemar Mk. I: four 230 h.p. Siddeley Puma. Engine Nos.: port front 6406.24080; port rear 6394.24068; starboard front 6399.24073; starboard rear 6368.24042. Braemar Mk. II: four 400 h.p. Liberty 12 (built by the Lincoln Motor Co.). Engine Nos.: port front 18020/601, W.D. No. 62068; port rear 18018/609, W.D. No. 62067; starboard front 18022/608, W.D. No. 62069; starboard rear 26172/2768, W.D. No. 65326.
  Dimensions: Span: top and centre 81 ft 8 in., bottom 78 ft 3 in. Length: 51 ft 6 in. Height: 20 ft 8 in. Chord: 8 ft 6 in. Gap: both 7 ft 2 1/2 in. Stagger: nil. Sweepback: 6° 30'. Dihedral: 2°. Incidence: 2° 30'. Airscrew diameter: front, Mk. I 9 ft 10 in.; Mk. II 10 ft; rear, Mk. I 9 ft 2 1/4 in.; Mk. II 9 ft 6 in. Tyres: Mk. I, 900 X 200 mm; Mk. II, 1100 X 220 mm.
  Areas: Wings: top 650 sq ft, middle 650 sq ft, bottom 605 sq ft, total 1,905 sq ft. Ailerons: each 48 sq ft, total 192 sq ft. Tailplanes: upper 51-5 sq ft, lower 45 sq ft, total 96-5 sq ft. Elevators: upper 42-5 sq ft, lower 42-5 sq ft, total 85 sq ft. Fins: two of 11-4 sq ft and one 5-2 sq ft, total 28 sq ft. Rudders: two of 7-6 sq ft and one 10-2 sq ft, total 25-4 sq ft.
Weights (lb) and Performance:
Braemar Mk. I Braemar Mk. I Braemar Mk. II
With 6 X 112-lb bombs With 5,000 lb load With 2,500 lb load
No. of Trial Report M.233a M.233a M.271c
Date of Trial Report September to September to February nth,
October, 1918 October, 1918 1920
Type of airscrew used on trial:
front P.3060 P.3060 A.B.22699
rear P.3065 P.3065 P.3084
Weight empty 9.578 9.578 11,208
Military load 345 305 828
Crew 720 540 680
Fuel and oil 3.635 1.355 3.496
Water 300 300 300
Weight loaded 14.578 12,078 16,512
Maximum speed (m.p.h.) at
5,000 ft 103-5 107 -
5,650 ft - - 122
6,500 ft 101 105-5 -
10,000 ft 95 101-5 -
13,000 ft - 98-5 -
14,400 ft - - 107-5
m. s. m. s. m. s.
Climb to
1,000 ft 1 50 1 20 1 00
2,000 ft 3 55 2 45 2 05
3,000 ft 6 10 4 15 3 15
4,000 ft 8 35 5 55 4 30
5,000 ft 11 15 7 35 5 55
6,000 ft 14 10 9 30 7 25
7,000 ft 17 35 11 35 9 00
8,000 ft 21 25 13 50 10 50
9,000 ft 26 05 16 25 12 50
10,000 ft 31 40 19 15 15 05
11,000 ft 38 50 22 30 17 40
12,000 ft - - 26 20 20 50
13,000 ft - - 30 50 24 30
14,000 ft - - - - 29 25
15,000 ft - - - - 36 20
Absolute ceiling (feet) 14,000 17.500 17,000

  Tankage: Braemar Mk. I. Petrol: four main tanks in fuselage: two port tanks of 107 gallons each, starboard front tank 103 gallons, starboard rear tank 105 gallons; two gravity tanks of 14 gallons each in top wing; total 450 gallons. Oil: four tanks, two between each pair of engines, 11 gallons in each; total 44 gallons. Water: 30 gallons. Braemar Mk. II. Petrol: four main tanks in fuselage, each of 105 gallons; two gravity tanks, each of 14 gallons, in top wing; total 448 gallons. Oil: four tanks, total 41 1/2 gallons. Water: 30 gallons.
  Armament: Racks for six 230-lb bombs were provided, and up to five Lewis machine-guns could be carried as follows: two on Scarff ring-mounting on nose cockpit, two on rocking-post mountings in dorsal cockpit aft of wings, one on Scarff ring-mounting on floor of fuselage aft of wings.
  Production: Two Braemars were built, one Mk. I and one Mk. II. The third airframe was completed as the Bristol Pullman.
  Serial Numbers: C.4296-C.4298: ordered under Contract No. A.S.38907. C.4296: Braemar Mk. I; C.4297: Braemar Mk. II; C.4298: completed as Bristol Pullman.

Bristol Scout F and F.1

  IN the design of the Bristol Scout F, Captain Barnwell gave further evidence of advanced thinking. Work on the design began in June, 1917, but the aeroplane would not have been accounted old-fashioned more than a decade later.
  In an age when most liquid-cooled aero-engines had their radiators installed car-fashion as a vertical surface immediately behind the airscrew, the Scout F represented a complete breakaway from contemporary practice with its radiator mounted under the fuselage. This position of the radiator allowed the cowling of the engine to be made commendably clean, and the aerodynamic entry of the aeroplane was unusually good.
  Structurally the Scout F was fairly typical of its period. The rear portion of the fuselage was a conventional wire-braced fabric-covered wooden structure, while the forward section was a plywood-covered box girder. The wings were of unequal span and chord, and both interplane and centre-section struts were of N configuration, thus eliminating the more usual incidence wires. Ailerons were fitted to the upper wings only.
  In the air the Scout F had excellent handling qualities, and was considered to be superior to the S.E.5a in some respects. Its performance was good, but it had a built-in liability in its Sunbeam Arab engine. When the Scout F was designed, it was not known that the Arab was going to prove so incurably unsatisfactory. All the troubles experienced with this engine in the Bristol Fighter were repeated with the Scout F, and there can be little doubt that the Arab was the chief reason why the machine did not go into production. Vibration was so severe that damage was caused to the engine bearers.
  Serial numbers were allotted for six machines, but in fact only three were completed and construction of a fourth did not proceed beyond the making of the bare airframe. The design was so promising that the British & Colonial Company did not wish to abandon it completely, and therefore sought an alternative power unit.
  The opportunity was taken to fit the Scout F with a new and untried radial engine, the Cosmos Mercury. This engine had been designed to fulfil the Air Board specification known as Scheme A, which had been issued on April 5th, 1917. Inspired by the Admiralty, Scheme A called for a stationary air-cooled radial engine not more than 42 inches in diameter and capable of delivering at least 300 h.p.
  Designs were submitted by Brazil, Straker & Co., Ltd., of Fishponds, Bristol, by Siddeley-Deasy, by Vickers, and by A.B.C. Motors Ltd. The winning design was the fourteen-cylinder two-row radial submitted by Brazil, Straker & Co., Ltd., and a production order for 200 engines was placed. The engine was named Mercury, and was designed by L. F. G. Butler, Brazil Straker’s chief designer, under the direction of A. H. R. (later Sir Roy) Fedden, who was the company’s chief engineer.
  The design of the Mercury was completed in July, 1917, and the first bench run was made early in 1918. At about that time the Brazil, Straker concern changed hands and was renamed the Cosmos Engineering Company.
  The Cosmos Mercury, as the engine was now known, was flown for the first time in April, 1918, installed in the third Bristol Scout F airframe, B.3991. With this engine the aircraft was designated Scout F.1. Despite the completely different configuration of the Mercury engine, care was again taken to keep drag down to a minimum. The day of the Townend ring and low-drag cowling had not yet arrived, but the Mercury was provided with a circular cowling through which the cylinder heads protruded.
  The performance of the Scout F.1 was excellent, particularly in rate of climb, but it was too late upon the scene to be considered for production. Moreover, the Cosmos company decided in the autumn of 1918 to concentrate on the development of their new single-row radial engine, the Jupiter, and the Mercury was virtually shelved. When the Armistice was signed, the contract for the 200 engines was cancelled, but testing continued into 1919. In April of that year the Bristol Scout F.1 set new climbing records when it reached 10,000 feet in 5-4 minutes and 20,000 feet in 16-25 minutes.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton and Brislington, Bristol.
  Power: Scout F: 200 h.p. Sunbeam Arab II. Scout F.1: 347 h.p. Cosmos Mercury.
  Dimensions: Span: upper 29 ft 7 1/2 in., lower 26 ft 2 in. Length: Scout F, 20 ft 10 in.; Scout F.1, 20 ft. Height: 8 ft 4 in. Chord: upper 5 ft 7 in., lower 4 ft 11 in. Gap: 5 ft 1 in. Stagger: 2 ft. Dihedral: 0°. Incidence: 1°. Span of tail: 10 ft 6 in. Airscrew diameter: Scout F, 9 ft 2 in.
  Areas: Wings: upper 150 sq ft, lower i 10 sq ft, total 260 sq ft. Ailerons: each 15-25 sq ft, total 30-5 sq ft. Tailplane: 15 sq ft. Elevators: 14-5 sq ft. Fin: 4-1 sq ft. Rudder: 5-3 sq ft.
  Weights and Performance: No. of Trial Report on Scout F: M.185. Date of Report: March, 1918. Type of airscrew used on trial of Scout F: P.3041. Scout F: weight empty: 1,436 lb. Military load: 319 lb. Pilot: 180 lb. Fuel and oil: 275 lb. Weight loaded: 2,210 lb. Scout F.1: weight loaded: 2,260 lb. Scout F: maximum speed at ground level: 138 m.p.h.; at 5,000 ft: 135 m.p.h.; at 10,000 ft: 128-5 m.p.h.; at 15,000 ft: 117-5 m.p.h. Climb to 6,500 ft: 5 min 20 sec; to 10,000 ft: 9 min 20 sec; to 15,000 ft: 17 min 20 sec. Service ceiling: 21,000 ft. Scout F.1: maximum speed at ground level: 145 m.p.h. Climb to 10,000 ft: 5 min 25 sec; to 20,000 ft: 16 min 15 sec.
  Tankage: Scout F. Petrol: main tank 29 1/2 gallons; service tank 3 gallons; total 32 1/2 gallons. Oil: 5 gallons. Water: 1 1/2 gallons.
  Armament: Two fixed Vickers machine-guns mounted on top of the fuselage and synchronised to fire forward through the revolving airscrew.
  Production: Three Scouts F were completed, and a fourth airframe was built. They were ordered under Contract No. A.S.3423.
  Serial Numbers: B.3989-B.3994. B.3991 was modified to become the Scout F.1; only the airframe of B.3992 was built; B.3993 and B.3994 were not built.

Bristol F.2C, the Badger

  DESPITE the great success achieved by the Bristol F.2B Fighter, Captain Barnwell was not content to rest upon his laurels. It had been realised that sooner or later a better aeroplane would be required as a replacement for the redoubtable Bristol Fighter and, to meet the new requirements, he began work on the design of a two-seat fighter, designated Bristol F.2C, in November, 1917.
  The original design was for a biplane powered by either a 230 h.p. Bentley B.R.2 engine or a 260 h.p. Salmson water-cooled radial, and deliberately designed to be easily produced in large quantities. However, neither of these power units was sufficiently powerful to give the required performance, but early in 1918 it seemed that the new A.B.C. Dragonfly radial engine held out great promise of high power for low weight, and Captain Barnwell, like so many contemporary designers, decided to use it for his new two-seat fighter.
  He produced a completely new design based on the Dragonfly, and it was this aeroplane which was built under the designation F.2C and named Badger. The initial order was for three prototypes numbered F.3495 - F.3497.
  The first machine, Badger Mk. I, was built with the Dragonfly engine and appeared in two forms: at first without spinner and with a more or less hemispherical cowling over the front of the engine, and later with a small spinner, more pointed cowling, and modified rudder. The first Badger crashed on February 4th, 1919. An air-lock in the fuel-line caused engine failure, and the undercarriage and engine installation were destroyed when the machine struck the ground. The second Badger was fitted with the new 450 h.p. Cosmos Jupiter nine-cylinder radial engine, and had a re-designed vertical tail incorporating a fixed fin; it was named Badger Mk. II. The third prototype was not built.
  Design of the Jupiter engine had begun early in 1918, almost immediately after Brazil, Straker & Co. had been renamed the Cosmos Engineering Co. As soon as the preliminary design was complete, A. H. R. Fedden submitted a sketch to the Air Board and in July, 1918, received an informal intimation of official interest in the proposed engine. By autumn, 1918, the Cosmos company were so convinced of the Jupiter’s superiority that they decided to concentrate on its development at the expense of the earlier Mercury engine. Designs were completed for two versions of the Jupiter: one was a direct-drive engine, the other had a planetary reduction gear.
  Soon after the cancellation of the contract for the 200 Cosmos Mercuries, the Government placed an order for six Jupiters. The first direct-drive Jupiter had been completed in October, 1918, and made its first bench run shortly before the Armistice. Its air tests were carried out in the Badger Mk. II during 1919, and ultimately it became the first engine to pass the new (in 1920) official 50-hour type test. By then the cost of developing the Jupiter had broken the Cosmos company, whose assets and patents were taken over in August, 1920, by the Bristol Aeroplane Company, who had been strongly pressed to do so by the Government.
  Despite early misgivings experienced by the Bristol company, the Jupiter was developed into an excellent power unit, and its development continued for many years.
  It is as a flying test-bed for the Jupiter that the Badger is best remembered. Badger F.3496 was flown as a simple two-seater with the Scarff ring removed from the rear cockpit and the side apertures glazed over, but later another Jupiter-powered Badger was built under a separate contract. This was numbered J.6492, and was fully equipped as a two-seat fighter with twin Vickers guns for the pilot and a Scarff ring for the observer. At first the rudder on this machine was identical to that of F.3496, but a balanced rudder was later fitted. The ailerons on J.6492 were balanced by small superimposed aerofoils in the same fashion as those of the Avro Manchester. This last Badger had a variety of engine cowlings during its career.


SPECIFICATION
  Manufacturers: The British & Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: Badger I: 320 h.p. A.B.C. Dragonfly I. Badger II: 450 h.p. Cosmos Jupiter.
  Dimensions: Span: upper 36 ft 9 in., lower 31 ft 4 in. Length: 23 ft 8 in. Height: 9 ft 1 in. Chord: upper 6 ft 2 in., lower 5 ft 6 in. Dihedral: 2°.
  Areas: Wings: 357-2 sq ft.
  Weights and Performance: No. of Trial Report on Badger I: M.263. Date of Report: September, 1919. Type of airscrew used on trial: P.3086. Weight empty: 1,948 lb. Military load: 334 lb. Crew: 360 lb. Fuel and oil: 510 lb. Weight loaded: 3,152 lb. Performance (with Dragonfly engine): maximum speed at ground level: 135 m.p.h.; at 6,500 ft: 131 m.p.h.; at 10,000 ft: 129 m.p.h.; at 15,000 ft: 122 m.p.h. Climb to 6,500 ft: 6 min 20 sec; to 10,000 ft: 11 min; to 15,000 ft: 20 min 30 sec. Service ceiling: 20,600 ft. (With Jupiter engine) Maximum speed at ground level: 142 m.p.h.
  Armament: Two fixed forward-firing Vickers machine-guns, synchronised to fire through the revolving airscrew; and one Lewis machine-gun on Scarff ring-mounting on the rear cockpit.
  Production: Three Badgers were built.
  Serial Numbers: F.3495-F.3497: ordered under Contract No. 35A/1122/C.994. (F.3497 was not built.) J.6492: ordered under Contract No. 35A/3312/C.3844.

de Havilland 1 and 1A

  THE Aircraft Manufacturing Company was established by G. Holt Thomas early in 1912. The company held the British rights for the manufacture of Farman aeroplanes, and was content to build them for a time; but Holt Thomas wanted to establish a design department in the firm, and in June, 1914, he secured the services of Geoffrey de Havilland.
  Mr de Havilland (now Sir Geoffrey) came to the Aircraft Manufacturing Co. with a wealth of experience of aircraft design and construction. Not only had he designed and flown the Royal Aircraft Factory’s most successful types during his period of service there, but he had also seen many examples of the products of other manufacturers which had gone to Farnborough to be tested. For the Aircraft Manufacturing Co. he designed a series of remarkably good aeroplanes, several of which made substantial contributions towards the attainment of supremacy in the air for the Allies. These aircraft earned for their designer the unique compliment of being known by his name rather than by that of the manufacturer: the numerical D.H. designations were seldom prefaced by “Airco”.
  The D.H. 1 was not Geoffrey de Havilland’s first design by any means, but it was the first aeroplane designed by him for the Aircraft Manufacturing Co. It was intended for reconnaissance and fighting duties, and the lack of a machine-gun interrupter gear inevitably made it a two-seat pusher biplane. It was powered by a 70 h.p. Renault engine, and appeared in January, 1915. The forward cockpit was occupied by the observer-gunner, who had a good field of fire in all forward directions. The wings were of two-bay construction, and the tail unit was supported on the customary tail-booms. The undercarriage of the prototype incorporated coil springs and concealed oleo-struts, and when it first appeared the D.H.1 was fitted with air-brakes. These consisted of two small aerofoils, each of about 3 feet span, disposed one on either side of the nacelle and pivoted on an axis which crossed the fuselage just behind the forward centre-section struts; they could be rotated through 90° to present a flat surface to the airstream. The air-brakes were not successful, however, and were soon abandoned.
  The test flights were made by Geoffrey de Havilland himself, and the D.H.1 had quite a good performance, despite the fact that it had been designed for a more powerful engine. The intention was to fit the 120 h.p. Beardmore as the standard power unit, but the Royal Aircraft Factory had laid claim to the few Beardmores which were available in 1914, and production of the D.H. design was delayed. Some were built with the Renault engine: these differed from the prototype in having exhaust manifolds which led the gases well forward, presumably to avoid damage to the airscrew. In the production machines the forward cockpit was cut much lower than on the prototype in order to facilitate the use of a gun, and the undercarriage relied on the more usual rubber cord for shock-absorption.
  When powered by the Beardmore engine the aircraft was re-designated D.H.1A, and was identical in appearance to the production D.H.1s apart from the bulkier upright engine with its radiator behind the pilot’s cockpit.
  By the time production could be undertaken, the Aircraft Manufacturing Co. were too busy with later designs, and the D.H.1A was built by Savages of King’s Lynn under sub-contract. The type never achieved any prominence; comparatively few were built, and only six went overseas. These went to the relative obscurity of the Middle East, and the others were distributed to Home Defence and training units. However, the D.H.1 design is of historic interest, not only as the first of the long line of distinguished D.H. types which was continued after the demise of the Aircraft Manufacturing Co., but also as the immediate predecessor of the more famous D.H.2.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: Savages, Ltd., King’s Lynn, Norfolk.
  Power: D.H.1: 70 h.p. Renault. D.H.1A: 120 h.p. Beardmore.
  Dimensions: Span: 41 ft. Length: D.H.1, 28 ft 11 5/8 in.; D.H.1A, 28 ft 11 1/4 in. Height: D.H.1, 11 ft 4 m.; D.H.1A, 11 ft 2 in. Chord: 5 ft 6 in. Gap: 5 ft 7 in. Stagger: nil. Dihedral: 3°. Incidence: D.H.1, 4° 30'; D.H.1A, 5° 15'. Span of tail: D.H.1, 12 ft 5 1/2 in.; D.H.1A, 12 ft 3 in. Wheel track: 5 ft 9 3/4 in. Airscrew diameter: D.H.1, 9 ft 0-4 in.; D.H.1A, 8 ft 10-3 in.
  Areas: Wings: upper 187 sq ft, lower 175-25 sq ft, total 362-25 sq ft. Ailerons: each 16 sq ft, total 64 sq ft. Tailplane: 37-5 sq ft. Elevators: 23 sq ft. Fin: 3-7 sq ft. Rudder: 15-4 sq ft.

Weights (in lb):
Empty Military load Crew Fuel and Oil Loaded
D.H.1: 1.356 60 360 268 2,044
D.H.1A: 1,610 40 360 330 2,340
 Performance: D.H.1: maximum speed at 3,500 ft: 80 m.p.h. Climb to 3,500 ft: 11 min 15 sec. D.H.1A: maximum speed at ground level: 90 m.p.h.; at 2,000 ft: 89 m.p.h.; at 4,000 ft: 88 m.p.h.; at 6,000 ft: 90 m.p.h.; at 8,000 ft: 90 m.p.h.; at 10,000 ft: 86 m.p.h.; at 12,000 ft: 84 m.p.h. Climb to 1,000 ft: 1 min. 40 sec; to 2,000 ft: 3 min 35 sec; to 3,000 ft: 5 min 55 sec; to 3,500 ft: 6 min 27 sec; to 4,000 ft: 8 min 15 sec; to 5,000 ft: 10 min 25 sec; to 6,000 ft: 13 min 10 sec; to 7,000 ft: 16 min 20 sec; to 8,000 ft: 19 min 30 sec; to 9,000 ft: 23 min; to 10,000 ft: 27 min 30 sec; to 11,000 ft: 32 min 25 sec; to 12,000 ft: 38 min 25 sec. Service ceiling 13,500 ft.
  Tankage: D.H.1: petrol 30 gallons. D.H.1A: petrol, main pressure tank, 35-3 gallons; service gravity tank, 5-5 gallons; total 40-8 gallons. Oil: 2-3 gallons. Water: 5 gallons.
  Armament: One Lewis machine-gun on pillar mounting in front cockpit.
  Service Use: No unit was completely equipped with D.H.1s or 1As. The type was issued to some Home Defence and training units, including No. 35 Reserve Squadron, Northolt. Six went to the Middle East Brigade in 1916, where some were used operationally by No. 14 Squadron, R.F.C.
  Production and Allocation: The total number of D.H.is and iAs delivered to the R.F.C. was seventy-three. Of that total, forty-three went to training units, twenty-four to Home Defence units, and six to the Middle East Brigade.
  Serial Numbers: 4606, 4607, 4615. A.1611-A.1660.
  Costs:
   Airframe, without engine, instruments and gun £1,100 0s.
   70 h.p. Renault engine £522 10s.
   120 h.p. Beardmore engine £825 0s.

de Havilland 2

  THE second de Havilland design which was built by the Aircraft Manufacturing Co. was a small single-seat fighting scout in which the designer’s first concern had been to give the pilot effective forward-firing armament. This, in the days before machine-gun interrupter gears, almost automatically meant a pusher aircraft; and as such the D.H.2 looked very much like a scaled-down D.H.1.
  Some histories seem to imply that the D.H.2 was deliberately designed and produced as a counter-weapon to the Fokker Monoplane, which, with its synchronised machine-gun, wrought great havoc among the Allied two-seaters in late 1915 and early 1916. In point of fact, the design of the D.H.2 was neither demanded nor prompted by the Fokker menace any more than was that of its companion Fokker-beater, the Royal Aircraft Factory F.E.2b: it simply so happened that these aeroplanes proved to be effective counter-weapons. The prototype D.H.2 completed its flight trials in July, 1915, at the time when the Fokker Monoplane was only beginning to be encountered; the first contract for quantity production was awarded during the following month, and the first production machine arrived in France in December, 1915.
  When the D.H.2 was designed, the technique of using a fixed gun and aiming the whole aeroplane at the target was not at first accepted by Britain, although it had been successfully demonstrated by French pilots. The prototype D.H.2 did not have a fixed machine-gun, nor even a central mounting for a semi-free weapon: instead, a movable bracket was fitted on each side of the cockpit in line with the windscreen, and from these the pilot was expected to aim his Lewis gun while flying his aircraft in the manoeuvres of combat. As a result, the nacelle of the prototype had a rather different appearance from that of the production D.H.2.
  For a pusher, the D.H.2 was remarkably neat and compact, and was of great structural strength. It was a two-bay biplane, and the tail-booms formed a V in plan; the tail-unit was obviously inherited from the D.H.1. The undercarriage was of the vee type, and the steerable tail-skid was mounted on an extension of the rudder post. The standard engine was the 100 h.p. Gnome Monosoupape rotary, but a version also existed with the 110 h.p. Le Rhone.
  The first R.F.C. squadron to be completely equipped with the D.H.2 was No. 24, which was commanded by Major Lanoe George Hawker, V.C. This unit had been formed at Hounslow on September 1 st, 1915, and received its D.H.2s at the end of the year. No. 24 Squadron had the distinction of being the first single-seat fighter squadron to go to any battle front when it flew its twelve D.H.2S from Hounslow to St Omer on February 7th, 1916. Two other D.H.2 squadrons followed: No. 29 on March 25th, and No. 32 on May 28th, 1916. Lieutenant Tidmarsh opened the scoring for No. 24 Squadron on April 2nd, 1916, when he shot down an enemy machine near Bapaume; and from that date onwards “Hawker’s Squadron” did much successful fighting.
  Although the D.H.2 eventually proved to be more pleasant to fly than any other contemporary pusher scout, operational or experimental, it was not at first popular with the pilots. It was extremely sensitive on the controls, a characteristic of great value in combat but, in an aeroplane with a small speed range, likely to cause the machine to spin easily. Until the D.H.2 pilots came to understand their mounts, several casualties were caused by spinning, for the phenomenon was not then understood. In one such accident the D.H.2 had caught fire while spinning, and the type was thereafter known by the unjustly grim soubriquet of “The Spinning Incinerator”. Second Lieutenant S. E. Cowan, M.C., of No. 24 Squadron did much to inspire the confidence of pilots in the aircraft by his skilful handling of his D.H.2, and he was the first pilot to stunt the type. The D.H.2 was capable of executing all normal aerobatics.
  Other dangers attended the flying of rotary-powered pushers, however. The historian of No. 24 Squadron recorded:
  “Two splendid pilots - Lieutenant Glew and Captain Wilson - were killed by cylinders blowing out and severing the tail-booms of their machines, and several other pilots, notably Captain Hughes Chamberlain and Lieutenant Sibley, had the narrowest of narrow escapes.”
  The gun-mounting on the production machines still had a certain amount of flexibility, but pilots soon adopted the technique of aiming the whole aeroplane at the target, and the gun’s flexibility was seldom used in combat.
  That the D.H.2 proved its worth soon after the arrival of the squadrons in France is borne out in the report written on May 23rd, 1916, by Sir Henry Rawlinson, General Officer commanding the Fourth Army:
  “... and the de Havilland machine has unquestionably proved itself superior to the Fokker in speed, manoeuvre, climbing, and general fighting efficiency.”
  The D.H.2 showed its mettle in many combats during the Battle of the Somme and on into 1917, but never better than on the evening of July 20th, 1916, when four of No. 24 Squadron’s machines, led by Captain R. E. A. W. Hughes-Chamberlain, fought eleven enemy aircraft over Flers and destroyed three of them.
  One of the earliest outstanding individual combats against great odds was that fought on July 1st, 1916, by Major L. W. B. Rees, the officer commanding No. 32 Squadron. Major Rees was flying a D.H.2, and was awarded the V.C. for his action. From a distance he saw a formation of ten enemy bombers, but at first he mistook them for British machines returning from a raid and flew over to join them, unaware that the formation had just shot down and killed one of his own pilots, Second Lieutenant J. C. Simpson, who had gallantly attacked single-handed. As soon as Rees recognised the nationality of the bombers he attacked them, forced two down, broke up the enemy formation and caused them to abandon the raid. Although wounded in the thigh, Major Rees fought until his ammunition was exhausted: only then did he break off the fight.
  Captain L. P. Aizlewood of No. 32 Squadron owed his life to the sturdy construction of the D.H.2. On September 9th, 1916, he was flying one of three D.H.2S which engaged five enemy machines over Thiepval. He dived on one of the German biplanes and closed to twenty yards before opening fire; but he was so intent on his target that his D.H.2 struck the tail of the enemy machine. Aizlewood’s propeller was smashed and his undercarriage wrecked, and the tail-booms were damaged, yet he brought his D.H.2 down near the British lines without being injured. His opponent crashed near Miraumont.
  No. 24 Squadron went far towards establishing a tradition of fighting against great odds. On September 15th, 1916, three D.H.2S attacked seventeen enemy aircraft near Morval, shot down two and scattered the remainder. On October 26th, five D.H.2s of the squadron fought twenty enemy single-seat fighters near Bapaume. Most of the German machines were Halberstadts, faster than the D.H.2s and able to outclimb their British adversaries; but the little pushers did not lose height when turning as the Halberstadts did, and so outfought the enemy.
  By this time, however, the D.H.2 had begun to be outclassed by the new Albatros and Halberstadt scouts, but replacement did not begin until March, 1917, During the winter of 1916-17 the type fought on gallantly and not without loss. But before the D.H.2’s star began to wane, it was indirectly responsible for the death of one of the early German fighting pilots of the first rank.
  On October 28th, 1916, Oswald Boelcke, victor in forty aerial combats, led his flight of six Albatros D.Is to attack two D.H.2s of “C” Flight of No. 24 Squadron; the British machines were flown by Lieutenant A. G. Knight and Second Lieutenant A. E. McKay. Boelcke dived to attack Knight at the same time as one of his pilots, Erwin Bohme, selected the same D.H.2 as his objective. Bohme’s undercarriage struck Boelcke’s upper wing, and the German leader dropped away from the fight with his Albatros apparently under control; but the wings later broke away and Boelcke went down to his death.
  One of the German pilots of Boelcke’s flight on that day was Manfred von Richthofen, who succeeded to the command of Jagdstaffel 2, and who, in less than a month, was to avenge his former leader’s death by depriving No. 24 Squadron of their Commanding Officer. On November 23rd, 1916, the D.H.2 of Major Lanoe George Hawker fell to Richthofen’s guns after one of the longest individual air combats of the war.
  Shortly before Hawker’s death, one who was to prove a worthy successor began his fighting career flying a D.H.2. This was Flight Sergeant (later Major) J. T. B. McCudden, who was a member of No. 29 Squadron. From a combat on 9th November, 1916, he brought his D.H.2 back with twenty-four bullet-holes in it - a greater number of hits than he sustained in any of his subsequent fights.
  No. 29 Squadron was the first D.H.2 squadron to be re-equipped. In March, 1917, it exchanged its pushers for Nieuport Scouts. Squadrons Nos. 24 and 32 received D.H.2s, but their re-equipment was not completed until June.
  The D.H.2 was not supplied in quantity to Home Defence squadrons, but in the early hours of the morning of June 17th, 1917, Captain R. H. M. S. Saundby attacked the Zeppelin L.48 over Theberton. He was flying a D.H.2 of the Orfordness Experimental Station, and attacked at the same moment as Lieutenant L. P. Watkins of No. 37 Squadron, who delivered the coup de grace to the enemy airship.
  A few D.H.2s were used in Palestine: No. 111 Squadron had three on its strength on October 27th, 1917; and the detachment of No. 14 Squadron, known as “X” Flight, which had begun its work of cooperating with the Arabs equipped with three B.E.12s, received one D.H.2 in October, 1917. In Macedonia, “A” Flight of No. 47 Squadron was equipped with D.H.2s, and continued to use them until the autumn of 1917, long after they were outclassed even in that secondary theatre of war. Two of No. 47’s D.H.2s were supplied to Lieutenant-General G. F. Milne at the end of March, 1917, as part of the R.F.C.’s contribution towards the creation of a composite fighter squadron. The rest of this mixed unit consisted of four of the R.F.C.’s B.E.12s, together with the R.N.A.S. contribution of four Sopwith 1 1/2-Strutters and a Sopwith Triplane.
  Official statistics record that one D.H.2 was sent to the B.E.F. in France in 1918, but by the autumn of that year none were left on charge of the R.A.F. The D.H.2 was essentially an aeroplane of the early period of the war in the air, but in its day it was nevertheless one of the most effective aerial weapons of the first World War.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Power: 100 h.p. Gnome Monosoupape; 110 h.p. Le Rhone.
  Dimensions: Span: 28 ft 3 in. Length: 25 ft 2 1/2 in. Height: 9 ft 6 1/2 in. Chord: 4 ft 9 in. Gap: 4 ft 9 in. Stagger: nil. Dihedral: 4°. Incidence: 3°. Span of tail: 10 ft 3 in. Wheel track: 5 ft 9 3/4 in. Airscrew diameter: Gnome 8 ft 0 1/4 in., Le Rhone 8 ft 2 1/2 in.
Areas: Wings: upper 128 sq ft, lower 121 sq ft, total 249 sq ft. Ailerons: each 14 sq ft, total 56 sq ft. Tailplane: 20-6 sq ft. Elevators: 13-5 sq ft. Fin: 2-7 sq ft. Rudder: 11 sq ft.

Weights (lb) and Performance:
Monosoupape Le Rhone
Empty 943 1,004
Military load 80 80
Pilot 180 180
Fuel and oil 238 283
Weight loaded 1,441 1,547
Maximum speed (m.p.h.) at
ground level 93 92
5,000 ft 90 85
6,500 ft 86 -
7,000 ft 85 85
9,000 ft 78 82-5
10,000 ft 77 -
I 1,000 ft 73-5 72

m. s. m. s.
Climb to
1,000 ft 1 10 - -
2,000 ft 2 30 - -
3,000 ft 4 30 4 35
4,000 ft 6 10 - -
5,000 ft 8 25 - -
6,000 ft 11 00 12 00
6,500 ft 12 00 - -
7,000 ft 14 00 - -
8,000 ft 17 00 - -
9,000 ft 20 30 23 30
10,000 ft 24 45 31 00
10,700 ft - - 46 00
I 1,000 ft 31 30 - -
11,700 ft 45 00 - -
Service ceiling (feet) 14,000 -
Endurance (hours) 2 3/4 3
Tankage (gallons):
Petrol: main tank 20-8 -
gravity tank 5-5 -
Total 26-3 33
Oil 5-1 5

  Armament: One Lewis machine-gun on flexible mounting in front of pilot, normally fixed to fire forward. Drums of ammunition were carried in racks outside the cockpit.
  Service Use: Western Front: R.F.C. Squadrons Nos. 24, 29 and 32. Some D.H.2s on strength of Squadrons Nos. 5, 11 and 18. Palestine: No. m Squadron and “X” Flight. Macedonia: “A” Flight of No. 47 Squadron; R.F.C. and R.N.A.S. Composite Fighting Squadron. Training: used at various training units, including No. 10 Reserve Squadron at Joyce Green.
  Production and Allocation: A total of 400 D.H.2s were delivered to the R.F.C., of which 266 went to the B.E.F. in France, thirty-two to the Middle East, two to Home Defence units, and 100 to training units.
  Serial Numbers: Between and about 5923 and 6008; 7842-7941; 8725 (renumbered ex-R.F.C. D.H.2 transferred to Admiralty as sample). A.2533-A.2632; A.4764-A.4813; A.4988-A.5087.
  Notes on Individual Machines: Used by No. 24 Squadron: 5925, 5964, 5989, 5991, 5998, 6007, 6008, 7884, 7909, 7918, 7930, A.2541, A.2544, A.2549, A.2563, A.2564, A.2581, A.2592, A.2606, A.5007, A.5018. Other machines: 5985: No. 29 Squadron. 7887: shot down September, 1916. A.2559 and A.4798: both of No. 10 Reserve Squadron.

de Havilland 3 and 3A

  THE D.H.3 appeared early in 1916, and was quite a remarkable aeroplane for its day. It was a handsome, workmanlike twin-engined biplane of unusual appearance, obviously capable of bombing duties, yet with a performance and defensive armament which would have enabled it to give a good account of itself in combat. The D.H.3 may in fact have been in the same category as the Bristol T.T.A.
  The low position of the fuselage permitted the use of a short undercarriage, and the machine sat low on the ground; there were two additional bumper wheels under the nose. The three-bay wings could be folded outboard of the engines, which were mounted midway between the wings. The engines of the D.H.3 were two 120 h.p. Beardmores, which drove pusher airscrews through short extension shafts: thus the airscrews were carried clear of the trailing edges of the wings and no cut-outs were necessary.
  The slim fuselage was of the normal wire-braced wooden construction, but the whole forward portion was covered with plywood. The pilot sat immediately in front of the leading edge of the lower wing; and there were cockpits for two gunners, one in the bows and one behind the wings. The tail-unit incorporated a shapely fin and rudder of the characteristic outline which for decades was to typify D.H. aeroplanes. The large tailplane carried horn-balanced elevators.
  The second version of the basic design was designated D.H.3A, and was fitted with two of the more powerful Beardmore engines of 160 h.p. each. In the D.H.3A, however, extension shafts were not used, and each engine drove a four-bladed airscrew. Cut-outs had to be made in the trailing edges of the mainplanes to allow the airscrews to revolve: these cut-outs reduced the wing area by 23 square feet. A curious feature was the fitting of a fairing of unusually wide chord to the rear centre-section strut, forming a vertical surface between the upper centre-section and the fuselage in line with the airscrews. The balance area of the rudder was enlarged, and made a slight hump in the otherwise smooth contour of the vertical tail surfaces. Stack-type exhausts with forward rake led the exhaust gases above the leading edge of the upper wing.
  Production was intended and serial numbers were allocated for an initial batch of fifty machines. It is believed that work was begun on at least the first production machine but was later abandoned. The experience gained with the D.H.3 and 3A was not lost, however, for the D.H.10 of 1918 was of similar configuration, and clearly owed much to the earlier design.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Power: D.H.3: two 120 h.p. Beardmore. D.H.3A: two 160 h.p. Beardmore.
  Dimensions: Span: 60ft 10 in. Length: 36 ft 10 in. Height: 14 ft 6 in. Chord: 6ft 9 in. Gap: 7 ft. Stagger: nil. Dihedral: 4. Incidence: 5. Span of tail: 23 ft 2 in. Airscrew diameter (D.H.3): 9-03 ft.
  Areas: Wings: D.H.3, 793 sq ft. D.H.3A, 770 sq ft. Ailerons: each 30-7 sq ft, total 122-8 sq ft. Tailplane: 78 sq ft. Elevators: 51 sq ft. Fin: 13 sq ft. Rudder: D.H.3, 21-3 sq ft; D.H.3A, 22 sq ft.
Weights: D.H.3. Empty: 3,980 lb. Military load: 40 lb. Crew: 540 lb. Fuel and oil: 1,250 lb. Weight loaded: 5,810 lb. D.H.3A. Weight loaded: 5,776 lb.
  Performance (D.H.3 only): Maximum speed at ground level: 95.1 m.p.h.; at 9,500 ft: 88 m.p.h. Climb to 1,000 ft: 2 min; to 2,000 ft: 5 min 12 sec; to 3,000 ft: 8 min 42 sec; to 4,000 ft: 12 min 12 sec; to 5,000 ft: 16 min 12 sec; to 6,000 ft: 20 min 48 sec; to 6,500 ft: 23 min 30 sec; to 7,000 ft: 26 min 24 sec; to 8,000 ft: 32 min 48 sec; to 9,000 ft: 43 min 30 sec; to 10,000 ft: 58 min. Endurance: 8 hours.
  Tankage: Petrol: 155 gallons. Oil: 12 gallons. Water: 8.5 gallons.
  Armament: Each gunner’s cockpit was provided with two pillar-type mountings for a Lewis machine-gun.
  Serial Numbers: 7744 (D.H.3A); A.5088-A.5137. (A.5088 was begun but not completed; the remainder were cancelled.)

de Havilland 4

  IN the D.H.4, Captain de Havilland produced one of the truly great aeroplanes of its day, one which had no peer among aircraft of its class in any of the combatant air forces, Allied or enemy. It was designed in response to an official request for an aeroplane to be used for day-bombing duties, and was the first British aircraft to be specifically designed for that purpose.
  The power unit originally specified for the D.H.4 was the 160 h.p. Beardmore. That engine had been developed from the 120 h.p. Beardmore by F. B. Halford, and it was thanks to his skill that the 33 1/3 per cent increase in output was achieved. By the time when the D.H.4 design was being prepared, Halford had secured the cooperation of Sir William Beardmore and T. C. Pullinger in the design and manufacture of a new engine, the 230 h.p. B.H.P., or Beardmore-Halford-Pullinger.
  The B.H.P. was similar to the Beardmore, for it was an upright six-cylinder in-line engine. It had, however, cylinders of cast aluminium monobloc construction with steel liners. In the adoption of this form of construction Halford had been inspired by the Hispano-Suiza engine, an example of which he had seen in France in 1915.
  The first B.H.P. engine was running in June, 1916, and gave good results. After successfully completing its bench tests, it was installed in the prototype D.H.4 instead of the specified 160 h.p. Beardmore. It was a taller engine than the Beardmore, a fact which doubtless accounted for the “step” in the top line of the engine cowling of the aeroplane. With the B.H.P. engine the D.H.4 appeared at Hendon in August, 1916. Difficulties were encountered in the quantity production of this engine, however; in fact, the first production B.H.P.s did not appear until the middle of 1917.
  Fortunately, an excellent alternative power unit was available: it was the 250 h.p. Rolls-Royce liquid-cooled vee-twelve engine which came to be known as the Eagle. This engine had originally been made for installation in seaplanes, but development and production had proceeded steadily from the time of the first bench test in May, 1915. The production Rolls-Royce engines had been coming off the lines since October, 1915, and by the end of 1916 sufficient quantities were available to enable the first production D.H.4s to be fitted with this type of engine.
  Tests of the D.H.4 with both the B.H.P. and Rolls-Royce engines were highly successful, and the happy union with the latter motor enabled sufficient machines to be produced to equip No. 55 Squadron, R.F.C., before it went to France on March 6th, 1917. Later marks of the superb Eagle engine were fitted to the D.H.4 as development of the motor progressed; and with the Eagle VIII, which delivered 375 h.p., the aircraft had a better performance than most contemporary fighters.
  The basic structural design of the D.H.4 was typical of its period. It was almost entirely made of wood, with wire cross-bracing and fabric covering. The fuselage was a conventional box-girder, but was made in two portions which were connected by fishplates immediately behind the observer’s cockpit; the forward portion was covered with plywood, which increased its strength considerably. The wings had two spruce spars, spindled out between the compression ribs, and the balance cables which interconnected the upper ailerons ran externally above the upper wing. The tailplane was also a wooden structure, and its incidence could be adjusted in flight by the pilot. The undercarriage was simple and strong: it consisted of two substantial wooden vees, to the apices of which the axle was bound by rubber cord.
  As the power of the engine was successively increased, larger airscrews were fitted, and it was found that the original undercarriage did not give sufficient ground clearance. A taller undercarriage was therefore fitted and became standard on all later production D.H.4s, regardless of the type of engine installed in the machine.
  The B.H.P.-powered prototype had its rear centre-section struts inclined forwards in side elevation; this arrangement did not appear in any production D.H.4s. There was a rather unsightly step-down in the top line of the engine cowling; the exhaust manifold terminated in a vertical stack which led the exhaust gases above the upper wing; and the engine drove a four-bladed airscrew.
  The B.H.P. engine had to be modified in several ways to make it suitable for large-scale production. An unfortunate result of these modifications was that when the first batch of engines was delivered to the Aircraft Manufacturing Co. in July, 1917, it was found that they would not fit the D.H.4s: the engine mountings in the aircraft had been designed from early drawings of the B.H.P. engine. The airframes had to be returned to the shops for modification, and production was delayed. The machines which emerged had a much neater engine installation than the B.H.P.-powered prototype; some had stack exhausts, but quite a number had a simple horizontal manifold.
  The various marks of Rolls-Royce Eagle had an exhaust manifold on each side of the engine: in many cases these manifolds were led up into twin stacks in front of the leading edge of the upper wing, but the stack extensions were not fitted to late production D.H.4s.
  Other alternative power units which were fitted to production D.H.4s were the 200 h.p. R.A.F. 3a vee-twelve, the 260 h.p. Fiat, and, as a natural alternative to the B.H.P. engine, the 230 h.p. Siddeley Puma. The R.A.F. 3a installation was characterised by a single central exhaust stack, a radiator which tapered slightly from top to bottom, and a four-bladed left-hand airscrew. This version of the D.H.4 was used by Squadrons Nos. 18 and 49.
  The installation of the Fiat engine made the nose of the D.H.4 resemble that of the later D.H.9; and this was the only production version of the machine which did not have a flat frontal radiator immediately behind the airscrew. The first installation was made in A.7532. The history of the Fiat-powered D.H.4s is of unusual interest. At the beginning of September, 1917, a hundred Russian pilots were receiving flying training in England, and fifty D.H.4s were under construction for the Russian Government. For these machines Russia had bought Fiat engines in Italy. At this time, however, the British War Cabinet decided to initiate a campaign of bombing raids on German towns in retaliation for the Gotha raids on London which had begun in September. In consequence of this decision it became imperative to augment the British bomber forces in France, and Russia was asked to forgo delivery of her fifty D.H.4s on the understanding that she would receive seventy-five in their place in the spring of 1918. Winter was approaching and operations on the Russian Front would be brought to a standstill by the weather, so the Russian Government agreed to the British request. On October 2nd, 1917, twenty of these D.H.4S were completed and crated for despatch to Russia, but as a result of the bargain they were diverted to the Western Front.
  No Fiat-powered D.H.4s were used operationally by the 41st Wing (the forerunner of the Independent Force), but the diversion of the Russian D.H.4s to other duties on the Western Front released Rolls-Royce D.H.4s for the independent bombing operations.
  A purely experimental engine installation in an early D.H.4 was that of a 300 h.p. Renault: this was probably made in France.
  Early production D.H.4s had the observer’s Scarff ring-mounting immediately on top of the upper longerons and below the level of the fuselage top-decking. With the gun-ring at this level, the decking interfered with the free movement of the gun and was rather low for comfort. In later D.H.4s the gun-ring was raised to the level of the top of the decking, thereby increasing the effectiveness of the observer’s weapon. The decking aft of the rear cockpit was flat-topped in these later machines.
  The early Westland-built D.H.4s supplied to the R.N.A.S. differed slightly from the standard machine. The Rolls-Royce Eagle was fitted, usually without radiator shutters, and in some machines the rocker-heads were cowled over. Twin Vickers guns were provided for the pilot in place of the customary single gun, and the observer’s gun-ring was built up to the top of the fuselage decking; the decking retained its rounded form right down to the tail, however. The weight of the additional Vickers gun and interrupter gear, and the drag of the externally mounted gun reduced the performance somewhat.
  In the air, the D.H.4 handled well for a two-seater, and the Central Flying School reported on it in the following glowing terms:
  “Stability. - Lateral very good; longitudinal very good; directional very good. Control. - Stick. Dual for elevator and rudder. Machine is exceptionally comfortable to fly and very easy to land. Exceptionally light on controls. Tail-adjusting gear enables pilot to fly or glide at any desired speed without effort.”
  That report related to the prototype, but the D.H.4 retained its good handling characteristics throughout its development. A later report on the version with the Eagle VIII engine notes that the machine tended to be tail-heavy at full speed and nose-heavy with engine off, but that the manoeuvrability remained very good.
  In performance the D.H.4 surpassed all contemporary aeroplanes in its class, and bettered most of the fighting scouts then in service. Its high ceiling particularly commended it to the bomber pilots of its day, and this desirable combination of speed, climb and tractability would at first glance seem to make the D.H.4 well-nigh invincible. More than once its speed and ceiling enabled it to escape from enemy fighters, but if it were intercepted and forced to fight it sometimes proved to be a comparatively easy victim. This vulnerability was attributed to the considerable distance which separated the pilot and observer.
  The cockpits were arranged to give the pilot a good forward and downward view for bombing, and the observer a good field of fire for his Lewis gun. Thus the pilot’s cockpit was situated immediately under the centre-section, and the observer was several feet further aft; the main fuel tanks occupied the intervening space. This arrangement succeeded in its original object, but the distance between the cockpits prevented that close and immediate cooperation between pilot and observer which was so essential in combat. The speaking-tube which connected the cockpits was of little practical use, and the fighting efficiency of the aeroplane suffered considerably from the separation of its crew. The observer had full dual control, with duplicated altimeter and air-speed indicator; his control column was detachable.
  No. 55 Squadron, R.F.C., took the first D.H.4s to France on March 6th, 1917, and from that day until the Armistice twenty months later the machine served with the R.F.C., R.N.A.S. and R.A.F. as a day-bomber, fighter-reconnaissance, photographic, anti-Zeppelin and anti-submarine aeroplane. No. 55 Squadron arrived in time to take part in the Battle of Arras, and made their first operational sortie on April 6th, 1917, when six D.H.4s attacked Valenciennes railway station. Valenciennes was attacked several times by the squadron, and on May 3rd the D.H.4s bombed the railway junctions at Busigny and Brebieres. Machines of this unit also carried out long-range photographic reconnaissances: these missions were flown by single D.H.4S at heights between 16,000 and 21,000 feet.
  No. 57 Squadron began to re-equip with D.H.4s in May, 1917, and was able to participate in the Battle of Ypres in company with No. 55 Squadron. In June, 1917, No. 18 Squadron was re-equipped with D.H.4s; No. 25 followed suit in July; No. 49 Squadron arrived in France on November 12th equipped with the type; and in the same month No. 27 Squadron began to replace their Martinsyde Elephants with D.H.4s. The four last-named squadrons were in action during the Battle of Cambrai, and in the period preceding the great German offensive of March, 1918, the D.H.4s of Nos. 25 and 49 Squadrons were employed on photographic reconnaissance.
  During the offensive itself, the D.H.4s of No. 5 (Naval) Squadron joined the day-bomber force, and all units were actively employed against the advancing enemy forces. Until March 25th, four days after the beginning of the enemy offensive, the D.H.4s had bombed from heights of 14,000 to 16,000 feet, and the effect of their bombs had been more moral than destructive. This height was adhered to because of an order issued in August, 1917, when D.H.4s were scarce, which stated that the type was not to be used below 15,000 feet. By March 25th, 1918, the situation had become so critical that Major-General J. M. Salmond had ordered the squadrons of the 9th Wing to make low-flying attacks; all risks were to be taken. This order concerned Squadrons Nos. 25 and 27, and on the following day No. 5 (Naval) Squadron was placed under similar orders. Despite unfavourable weather, these units carried out their orders to the letter, and played a leading part in harassing enemy troops. Low-flying attacks were also made by Nos. 18 and 49 Squadrons, but by March 31st the D.H.4s were able to resume bombing from more comfortable altitudes.
  When the German forces were beaten back throughout the summer and autumn of 1918, the D.H.4s again gave of their best. They acquitted themselves with more distinction than the D.H.9s, which were then coming into service and were replacing the D.H.4 in several squadrons. No. 205 Squadron, R.A.F. (as No. 5 Naval had become on April 1st, 1918), distinguished itself in repeated attacks on strategic bridges, and during four days in August, 1918, the D.H.4s of this unit flew for 324 hours 13 minutes and dropped a total of 16 tons of bombs.
  At the beginning of October, 1917, No. 55 Squadron had been withdrawn from the British front, and became one of the three units composing the 41st Wing: the two others were No. too (F.E.2b) Squadron and No. 16 (Naval) Squadron, which had Handley Page O/100s. These squadrons formed the nucleus of what was successively named the VIII Brigade and, on June 6th, 1918, the Independent Force, R.A.F. From their base at Ochey they carried out the first organised programme of strategic bombing.
  On October 17 th, 1917, eight of the D.H.4s of No. 55 Squadron made their first raid after joining the 41st Wing. The objective was Saarbrucken, which was revisited many times by No. 55 in the course of the ninety-four further sorties made by the squadron before the Armistice. Other towns in which the D.H.4s made the lot of the munition workers an unhappy one were Mannheim, Metz-Sablon, Kaiserslautern, and Frankfurt. Raids on Frankfurt, Duren and Darmstadt extended the D.H.4s to the limit of their maximum endurance of five and a half hours, and there was no safety margin for combat. In Cologne, a minor panic followed an attack by six D.H.4s on May 18th, 1918, for the town had been attacked only twice before. That was not the only occasion on which No. 55 Squadron bombed Cologne, however.
  These operations cost No. 55 Squadron sixty-nine D.H.4s. Eighteen were missing and fifty-one wrecked.
  The R.N.A.S. began to receive D.H.4s in the spring of 1917, and the first overseas unit to receive the type was No. 2 (Naval) Squadron at St Pol, followed by No. 5 (Naval): the latter unit had completely replaced its Sopwith 1 1/2-Strutters by the middle of August, 1917. In addition to day-bombing attacks, these R.N.A.S. D.H.4s did much useful coastal patrol work. The D.H.4s of No. 202 Squadron spent weeks in taking photographs of the whole area and defence system around Zeebrugge before the naval attack of April 22nd/23rd, 1918.
  For anti-submarine patrol, No. 17 (Naval) Squadron was formed with D.H.4s on January 13th, 1918; and 1918 saw the former Naval fighting squadrons Nos. 6 and 11 revived and initially equipped with D.H.4s. The submarine U.B.12 was sunk on August 12th, 1918, by four D.H.4s of No. 217 (formerly No. 17 Naval) Squadron. Captain K. G. Boyd scored direct hits with his two 230-lb bombs.
  R.N.A.S. units in England received D.H.4s for anti-Zeppelin patrols. Great Yarmouth air station received its first D.H.4 in August, 1917, and welcomed it as an overdue replacement for the B.E.2c’s which had been the unit’s best night-flying aeroplane up to that time. On August 26th two D.H.4s of unusual interest arrived at Great Yarmouth. These were special long-range machines, powered by the R.A.F. 3a engine and fitted with tanks which would give them an endurance of about fourteen hours.
  The long-range D.H.4s had been specially modified to make a photographic reconnaissance of the Kiel Canal. The take-off was to have been made from Bacton, whence the machines were to fly across the North Sea, take their photographs, and land at Dunkerque. These D.H.4s were specially camouflaged with matt dope of fawn and blue. They were flown to Bacton on August 9th, 1917, but a few days later the Admiralty decided not to proceed with the plan, and the D.H.4s were sent to Great Yarmouth for anti-Zeppelin duties.
  On September 5th, 1917, one of the Great Yarmouth D.H.4s collaborated with the Curtiss H.12 flying-boat No. 8666 in attacking the Zeppelin L.44. The airship escaped, but the D.H.4 developed engine trouble and had to ditch. The port engine of the flying-boat was not running well, but Flight-Lieutenant R. Leckie went down at once and rescued Flight-Lieutenant A. H. H. Gilligan and Lieutenant G. S. Trewin from the wreckage of their D.H.4. This early attempt at air-sea rescue nearly ended in disaster, for the flying-boat was unable to take off again. Leckie taxied towards England until his fuel ran out, and the six men were not picked up until September 7th when they were sighted by H.M.S. Halcyon.
  These R.N.A.S. D.H.4s had no flotation gear of any kind, but experiments with the Grain Flotation Gear were carried out at the Marine Experimental Aircraft Depot, Isle of Grain. D.H.4s with Siddeley Puma and R.A.F.3a engines were used; one of the Puma-Fours was tested with flotation gear in January, 1918. Tests were also carried out with D.H.4s which had a biplane hydrovane mounted ahead of the undercarriage: the wheels were jettisoned by means of compressed air before alighting. Inflatable canvas bags were attached to the lower longerons and small stabilising floats were fitted under the lower wingtips.
  A twin-float version of the D.H.4 existed, and may have been an attempt to provide a patrol seaplane with a worthwhile performance. The D.H.4 seaplane had a Rolls-Royce Eagle engine, and its floats resembled those of the Wight seaplanes; there was no tail float.
  A D.H.4 from Great Yarmouth shot down the Zeppelin L.70 on August 5th, 1918. On board the airship was Fregattenkapitan Peter Strasser, the Commander-in-Chief of the Imperial German Naval Airship Service, and his death was a severe blow to the enemy. The D.H.4, A.8032, was flown by Major Egbert Cadbury, and his gunner was Captain Robert Leckie, D.S.O., D.S.C. Cadbury attacked the airship from ahead and slightly to port at a height of 16,400 feet about forty miles north-east of Yarmouth. Leckie’s Lewis gun was loaded with Z.P.T. ammunition which instantly set fire to the Zeppelin, and Cadbury later estimated that the whole ship was consumed by the flames in about three-quarters of a minute. Cadbury then turned on the L.65, which was accompanying the L.70, but Leckie’s gun jammed and the airship escaped.
  At the time, it could not be known that the night of the L.yo’s end marked the last of the Zeppelin raids on the United Kingdom, and work continued on various means of overcoming the Zeppelin menace. It was thought that the Coventry Ordnance Works 1 1/2-pounder quick-firing gun would be an effective weapon for anti-airship work, and two D.H.4s were specially modified to carry a gun of this type: one of these machines was A.2168. In these D.H.4s the gun was fixed to point upwards at an acute angle; the breech was close to the floor of the rear cockpit, and the muzzle protruded through the upper centresection, which had to be covered with sheet metal to withstand the blast. The gun was aimed in a fashion similar to that adopted on Home Defence Bristol Fighters. The pilot had a sight mounted parallel to the C.O.W. gun, and this he aligned with the target by careful use of the. elevators, whereupon he gave the gunner the signal to fire.
  The airframes of the D.H.4s had to be extensively strengthened to withstand the recoil of the gun; consequently they were overloaded and rather unpleasant to fly. An added discomfort for the pilot was the firing of the gun immediately behind his head.
  By the time the C.O.W.-gun D.H.4s were ready, Zeppelin raids on the United Kingdom had ceased. A night test over the enemy lines was ordered, but the Armistice was signed a few days after the machines arrived in France, and they saw no operational service.
  The D.H.4 was used in experiments with the provision of parachutes for aircrew. A Puma-powered D.H.4 was tested with two Guardian Angel parachutes in November, 1918.
  Further experimental engine installations were tested in 1918. One was the 400 h.p. Sunbeam Matabele, which was flown in the D.H.4 numbered A.8083. The engine was a vee-twelve with cylinders of the same bore and stroke as those of the Sunbeam Saracen, an earlier six-cylinder in-line engine.
  Of much greater significance was the installation in a D.H.4 of the experimental Ricardo-Halford Inverted Supercharger engine. F. B. Halford first met H. R. (later Sir Harry) Ricardo early in 1916, and soon became his enthusiastic disciple and collaborator. Ricardo did a prodigious amount of inspired work in the design of aircraft engines and the development of their fuels, but his pioneering efforts have received comparatively little recognition.
  In 1918 Ricardo and Halford, working independently of the Royal Aircraft Factory’s experiments with supercharged engines, collaborated in the design of the Ricardo Supercharger, one of the first engines to be designed from the start as a supercharged power unit. When it was completed, the engine was unusually tall, and it would have been difficult to devise an installation which did not block the pilot’s view. Halford conceived the idea of inverting the engine, and did much of the design work connected with the necessary modifications. The Ricardo-Halford Inverted Supercharger was installed in a D.H.4 and was successfully flown at Farnborough.
  The first D.H.4s to reach Mesopotamia were two which were allotted to No. 30 Squadron. Neither survived for long: one received a direct hit by an anti-aircraft shell and blew up in the air on January 21 st, 1918, and the second caught fire at 1,000 feet during a raid on Kifri on the night of January 25th/26th. The latter machine landed in time to enable its crew to escape.
  Later, a few D.H.4s were on the strength of “A” Flight of No. 72 Squadron, which had arrived at Basra on March 2nd.
The R.N.A.S. units on the Aegean Islands of Imbros, Lemnos, Mitylene and Thasos used D.H.4s. The unit known as “C” Squadron moved to a new aerodrome at Gliki, on Imbros, in October, 1917; and during the following month the two D.H.4s which had been sent to reinforce the squadron began a series of attacks on the main Sofia-Constantinople railway.
  On January 20th, 1918, the D.H.4s of the R.N.A.S. began a sustained attack on the German cruiser Goeben when she had run aground in the Narrows after coming out of the Dardanelles. The attacks continued by day and night until January 24th, but no hits were scored, and the Goeben returned to Constantinople on the 27th. A watch was kept on her as she lay at her moorings in Stenia Bay by D.H.4s specially fitted with long-range tanks to ensure an endurance of seven hours.
  One of the D.H.4s from Mudros went to the aerodrome at Amberkoj on September 24th, 1918, to assist No. 17 Squadron in its attacks on the retreating Bulgars.
  The Italian-based D.H.4s of the 66th and 67th Wings made several attacks on the enemy submarine bases at Cattaro and Durazzo. Attacks on Cattaro entailed a flight of 400 miles over the sea.
  Among the machines which went to northern Russia with the R.A.F. contingent in May, 1918, were eight D.H.4s with R.A.F. 3a engines: these operated with a special force which was sent to Archangel. Later in the campaign some Fiat-powered D.H.4s joined the R.A.F. contingent. After the Armistice was signed, the R.A.F. remained on active service in Russia, and another unit was set up at Baku in January, 1919, to support British naval forces in the Caspian Sea. The equipment of this unit included D.H.4s which carried out bombing raids on Astrakhan and other ports until October, 1919, when the R.A.F. unit was recalled. At least one D.H.4 was used by the Red aviation service after it had been captured intact.
  Of all the British aeroplanes which were selected for production in America, only the D.H.4 was produced in substantial numbers. It was the only American-built British type to see operational service in France.
  Even before the Liberty engine was designed, the original procurement programme of 7,375 aeroplanes presented to the Secretaries of the War and Navy Departments on May 25th, 1917, included 1,700 D.H.4s. The fact that the D.H.4 was obviously capable of using the American-designed Liberty 12 engine made it highly desirable in American eyes.
  The first D.H.4 to be flown in America was a British-built machine which had been delivered, without engine, to Dayton, Ohio, on August 15th, 1917. Ten days later the first Liberty 12 successfully completed a fifty-hour bench run, and was rated at 314 h.p. By October, 1917, the power output had been raised to 395 h.p., and on the 29th of that month the engine was flown in the D.H.4 for tbe first time.
  Contracts for the production of the D.H.4 were placed with the Dayton-Wright, Fisher Body and Standard concerns, from whom a total of 9,500 machines were ordered; and by the time of the Armistice these manufacturers had produced a total of 3,227 Liberty-powered D.H.4s. The first production aircraft were delivered by Dayton-Wright in February, 1918. Before the end of the war, 1,885 American-built D.H.4s were despatched to France for the use of the American Expeditionary Force, and the type was used operationally by twelve squadrons. The first American-built D.H.4 joined the A.E.F. on May 11 th, 1918.
  Development proceeded in America, and in July, 1918, the Engineering Division of the Bureau of Aircraft Production installed a revised fuel system in a D.H.4, which was thereupon re-designated D.H.4A (but should not be confused with the British post-war commercial D.H.4A). The second modification of the D.H.4, made in October, 1918, by the Engineering Division, was the D.H.4B. This was the D.H.4A with the positions of the pilot and fuel tanks interchanged.
  American production ceased with the Armistice, when seven contracts for a total of 7,502 D.H.4s were cancelled; but during the period 1919-23 many hundreds of D.H.4s were converted to D.H.4Bs: 1,538 were modified by ten different contractors from February, 1919, onwards, and many others were similarly converted by air depots. The type survived for many years in America, and scores of variants of the basic design appeared over the years. In 1923-24, some 285 D.H.4s and D.H.4Bs were given steel tube fuselages by the Atlantic and Boeing concerns: these machines were re-designated D.H.4M, D.H.4M-1 and D.H.4M-2. Numbers of surplus D.H.4s were taken over by the Post Office Department in 1919, and were modified to carry air-mail: in this capacity the type served until 1927. This version of the D.H.4 was not particularly pleasant to fly and was not popular with its pilots. The first twelve machines converted by the L.W.F. Engineering Co. were fitted with a rain-proof compartment for 500 lb of mails in what was originally the front cockpit. The machine was flown from the rear seat, and a steel tube undercarriage was fitted.
  At home, the post-war use of the D.H.4 was almost wholly commercial in character, beginning with its use by the R.A.F. Communications Wing during the 1919 Peace Conference, when a London-to-Paris service was operated. In that year a cabin version, designated D.H.4A, appeared: there was accommodation for two passengers. Another post-war version was the drastically modified D.H.4R racer with clipped lower wings and a 450 h.p. Napier Lion engine. The D.H.4R won the 1919 Aerial Derby, and was capable of 150 m.p.h.
  In July, 1919, a D.H.4 was used to test an experimental Rolls-Royce engine known as the Experimental G. This power unit gave 353 h.p. at 1,800 r.p.m.
  After the end of the war, D.H.4s were sold to Greece and Spain, and individual machines went as far afield as Japan, New Guinea and Australia. In Canada, the type was used as a forestry patrol aircraft for several years.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: F. W. Berwick & Co., Ltd., Park Royal, London, N.W.10. Westland Aircraft Works, Yeovil, Somerset. Vulcan Motor and Engineering Co. (1906), Ltd., Crossens, Southport.
  American Contractors: The Dayton-Wright Airplane Co., Dayton, Ohio; The Fisher Body Corporation; Standard Aircraft Corporation, Elizabeth, New Jersey.
  For conversions to D.H.4B: The Aeromarine Plane and Motor Co., Keyport, New Jersey; Gallaudet Aircraft Corporation, East Greenwich, Connecticut; The L.W.F. Engineering Co., College Point, New York; Thomas-Morse Aircraft Corporation, Ithaca, New York.
  Power: 230 h.p. P.H.P. (both Galloway and Siddeley-made); 230 h.p. Siddeley Puma; 250 h.p. Rolls-Royce Mk. Ill (Eagle III); 275 h.p. Rolls-Royce Mk. II (322 h.p. Eagle VI); 275 h.p. Rolls-Royce Mk. Ill (325 h.p. Eagle VII); 375 h.p. Rolls-Royce Eagle VIII; 353 h.p. Rolls-Royce Experimental G engine; 200 h.p. R.A.F. 3a; 400 h.p. Sunbeam Matabele; 260 h.p. Fiat; 300 h.p. Renault; 400 h.p. Liberty 12; Ricardo-Halford Inverted Supercharger.
  Dimensions: Span: 42 ft 4 5/8 in. (American-built D.H.4: 42 ft 5 3/4 in.). Length: 29 ft 8 in. with R.A.F. 3a and Fiat engines, 30 ft 8 in. with Rolls-Royce and Puma engines, 30 ft 5 61/64 in. with Liberty. Height: 10 ft 1 in. with B.H.P., Puma and Rolls-Royce G engines; 10 ft 3 20/32 in. with Liberty; 10 ft 5 in. with R.A.F. 3a, Eagle III and Fiat engines; 11 ft with Eagle VIII engine. Chord: 5 ft 6 in. Gap: 5 ft 6 in. Stagger: 12 in. Dihedral: 30. Incidence: 30. Span of tail: 14 ft (American-built D.H.4: 13 ft 7 in.). Wheel track: 6 ft. Airscrew diameter: B.H.P. and Eagle III, 8 ft 9 in.; Fiat, 8 ft 11 in.; R.A.F. 3a, 10 ft; Eagle VIII, 10 ft 2 in.
  Areas: Wings: upper 223 sq ft, lower 211 sq ft, total 434 sq ft. Ailerons: each 20-5 sq ft, total 82 sq ft. Tailplane: 38 sq ft. Elevators: 24 sq ft. Fin: 5-4 sq ft. Rudder: 13-7 sq ft.

Tankage (in gallons):
Petrol Oil Water
230 h.p. B.H.P. 62 1/2 5 1/2 6
250 h.p. Rolls-Royce 65 4 1/2 -
Rolls-Royce Eagle VIII 65 3/4 5 1/2 9
R.A.F. 3a 65 1/2 4 1/2 -
Fiat 65 5 8
Liberty 88 - -

  Armament: Standard armament consisted of one fixed forward-firing Vickers machine-gun mounted on top of the fuselage to port of centre and synchronised by Constantinesco gear; the observer had either a single Lewis gun or a double-yoked pair on the Scarff ring-mounting on the rear cockpit. The Westland-built D.H.4s for the R.N.A.S., some of which were diverted to the R.F.C., had twin Vickers guns for the pilot, and some R.N.A.S. machines had Lewis guns on separate pillar-type mountings in the rear cockpit instead of the Scarff mounting. American-built D.H.4s had two fixed Marlin machine-guns and twin Lewis guns for the observer. Bomb racks were fitted under the fuselage and each lower wing: the bomb load consisted of two 230-lb, four 112-lb bombs, or their equivalent. Depth charges could be carried instead of bombs.
  British Production and Allocation: Production of D.H.4s totalled 1,449. Of these, 1,170 were delivered to the R.F.C. and R.A.F.; presumably the remainder went to the R.N.A.S. and into store. 664 went to the Expeditionary Force in France; ninety-one to the Independent Force; eighteen to the Middle East Brigade; one to the Mediterranean in 1918; sixty-seven to the 5th Group in 1918 for anti-submarine patrol (Squadrons Nos. 202 and 217); one to a Home Defence unit in 1917; and 328 to training units.
  On October 31st, 1918, the R.A.F. had on charge 548 D.H.4s; 373 with Rolls-Royce engines, seventy-two with R.A.F. 3a, ninety-eight with B.H.P., and five with Fiat. These were distributed as follows:
Rolls-Royce R.A.F. 3a B.H.P. Fiat
With E.F. in France 120 25 12 1
Independent Force 70 - - 2
5th Group 37 - - -
In transit to Middle East - 4 - -
Mesopotamia - 9 - -
Mediterranean 2 4 20 -
Attached to Grand Fleet 4 - - -
11th (Irish) Group - 3 3 -
Training units - - 17 -
Sundry home units 27 17 44 2
Aeroplane Repair Depots 75 6 1 -
With contractors 15 4 1 -
In store 23 - - -
Totals 373 72 98 5

  Service Use: Western Front: R.F.C. Squadrons Nos. 18, 25, 27, 49, 55 and 57; R.N.A.S. Squadrons Nos. 5, 6 and 11 (later Nos. 205, 206 and 211, R.A.F.); American units, 8th, nth, 20th, 50th, 85th, 100th, 135th, 155th, 166th, 168th, 278th and 354th Aero Squadrons. The 96th Aero Squadron had a few D.H.4S. Some were used by the U.S. Naval Northern Bombing Group. Coastal Patrol: R.N.A.S. Squadrons Nos. 2, 5 and 17 (later Nos. 202, 205 and 217, R.A.F.), No. 212 (part only), No. 273 (part only), R.N.A.S. Stations Port Victoria and Redcar. Home Defence: R.N.A.S. Great Yarmouth (later No. 212 Squadron, R.A.F.). Mesopotamia: No. 30 Squadron had two D.H.4s; No. 72 Squadron, “A” Flight. Macedonia: one D.H.4 from Mudros (probably No. 223 Squadron) attached to No. 17 Squadron. Aegean: “C” Squadron, Imbros. “D” Squadron, Stavros. R.N.A.S. Station, Mudros. 62nd and 63rd Wings (Squadrons Nos. 220, 221, 222 and 223). Adriatic: 66th and 67th Wings (Squadrons Nos. 224, 225, 226 and 227). Russia: R.A.F. contingent at Archangel (May, 1918) had eight D.H.4s with R.A.F. 3a engines. Fiat-powered D.H.4s were later used in northern Russia. Training: No. 51 Squadron. Air Observers’ Schools at Mansion, New Romney and Eastchurch. School of Photography, Maps and Reconnaissance, Farnborough. Schools of Navigation and Bomb-dropping, Andover, Stonehenge and Thetford. Aerial Fighting Schools at Turnberry, Marske and Sedgeford. No. 10 Training Depot Squadron, Harling Road. No. 31 Training Squadron, Wyton. American version used at Ford junction, Sussex.

Serial Numbers:
Serial No. Contractor Contract No.
3696 Aircraft Manufacturing Co.
A.2125-A.2174
A.7401-A.8089 Aircraft Manufacturing Co. 87/A/496
B.1482
B.2051-B.2150 F. W. Berwick & Co., Ltd.
B.3957-B.3960 Westland-built R.N.A.S.-type D.H.4s, probably renumbered from N series
B.5451-B.5550 Vulcan Motor Co.
B.9476-B.9500 Westland Aircraft A.S.29679
C.4501-C.4540 Aircraft Manufacturing Co. A.S.24960
D.1751-D.1775 Westland Aircraft A.S.29679
D.8351-D.8430 Aircraft Manufacturing Co. A.S.37726
D.923I-D.9280 Aircraft Manufacturing Co.
Between, and about
F.2635-F.2704 -
Between and about
F.5715-F.5828 -
About F.7597 -
N.5960-N.6009 Allotted for D.H.4s to be built by Westland Aircraft, but only the following were delivered: N.5960-N.5990, N.5992, N.5996, N.5997, N.6000, N.6001, N.6004, N.6005, N.6007, N.6009.*
N.6380-N.6399 Allotted for D.H.4s, but N.6393 and N.6397 were not delivered with N. serials.*
N.6400-N.6429 Westland Aircraft
* The missing D.H.4s in these batches may have been delivered to the R.F.C. and renumbered; e.g. B.3957.

Notes on Individual Machines: Used by No. 5 (Naval) Squadron, later No. 205 Squadron, R.A.F.: A.7518, A.7573, A.7620, A.7644, A.7664, A.7739, A.7742, A.7811, A.7908, A.7939, A.7964, A.8071, A.8084, D.9232, D.9238, D.9241, D.9243, N.5962, N.5967, N.5968, N.5971, N.5974, N.5977, N.5978, N.5982, N.5996, N.6000, N.6001, N.6004, N.6005, N.6008, N.6009. Used by No. 17 (Naval) Squadron, later No. 217 Squadron, R.A.F.: A.7772, A.7773, A.7846, A.7863, A.7867, A.7870, A.7875, A.7925, A.7935, A.7964, A.8013, A.8022, A.8050, A.8056, A.8059, A.8067, A.8072, D.8353, D.8366, D.8370, D.8393. Used at R.N.A.S. Station, Mudros: N.6410, N.6411, N.6420. Used by “C” Squadron, R.N.A.S., Gliki, Imbros: N.5975, N.5976. Used by No. 18 Squadron, R.F.C.: A.7550 (R.A.F. 3a engine), A.7594, A.7614, A.7653, A.7815, A.7907, A.8000, A.8041. Used by No. 25 Squadron: A.7442 (“B”), A.7477, A.7479, A.7482, A.7486, 7489, A.7505. Used by No. 27 Squadron: A.7677, B.2077. Used by No. 51 Squadron: A.2134, A.2138, 3960. Used by No. 55 Squadron: A.2130, A.2144, A.2145, A.2150, A.2159, A.2161, A.7418, A.7421, A.7469, A.7791. Used by No. 57 Squadron: A.2138, A.2174, A.7424, A.7492, A.7510, A.7554, A.7555, A.7563, A.7564, A.7568, A.7904, D.8419, D.8425, D.9262, F.2635, F.5828. Used at No. 1 School of Navigation and Bomb-dropping, Stonehenge: A.2136, A.7871, B.5483. Other machines: A.7483, “Australia No. 5, N.S.W. No. 4. The F. J. White, Saumarez and Baldblair”. A.7488, “Australia No. 18, N.S.W. No. 17, Government”. A.7559, became prototype D.H.9. A.7864, “Felixstowe”, R.A.F. 3a engine. A.8083, experimental installation of Sunbeam Matabele engine. D.8380, “The Women of Malaya, Malaya No. 27”. N.5984: “D” Squadron, R.N.A.S., Stavros. N.5985: No. 2 (Naval) Squadron. N.6404, R.N.A.S. Port Victoria; 230 h.p. B.H.P. engine.
  Costs:
   D.H.4 airframe (for R.A.F. 3a engine) without engine, instruments and armament £1424 10s.
   R.A.F. 3a engine £1,210 0s.
American Production and Deliveries:
Contracts:
Contractor Order No. Quantity ordered Number delivered Notes
Dayton-Wright 20038-A 4,000 3,098
20038-4 7 7 Remodelling order
20038-44 1,000 None
20529-1 6 6
Fisher Body 20207-A 4,000 1,600
Standard 20516 500 None Order cancelled
20516-A 500 140

As at November 11th, 1918:
Total U.S. production 3,227
Despatched by sea 1,885
Received overseas (unassembled) 1,185 in France
Assembled overseas 1,025
Put into service 984
In service at the Front 628
In commission at the Front 457

de Havilland 5

  THE D.H.5 was designed in 1916, when D.H.2 and F.E.8 pusher scouts were still in service. By that time, however, several British synchronising gears for machine-guns had become available to designers, and the way was clear for the combination of forward-firing armament and the superior performance of the tractor aeroplane. The last great asset of the pusher layout was the excellent forward view from the cockpit, and the peculiar design of the D.H.5 was the result of attempting to provide a tractor aeroplane with the uninterrupted forward outlook of the pusher.
  The manner of achievement of this compromise was unconventional. The mainplanes were rigged with a pronounced backwards stagger of 27 inches, and the pilot sat below and in front of the leading edge of the upper wing. Otherwise the machine’s structure was fairly typical of its time. The fuselage was basically a wooden box-girder with wire cross-bracing, and in the prototype D.H.5 was flat-sided with a rounded top-decking and fairings behind the engine cowling on either side. The same basic structure remained in production machines, but the fairing of the engine cowling was carried smoothly into the lines of the fuselage which, aft of the centre-section struts, was of octagonal cross-section. The fuselage was made in two parts joined at the line of the rear centre-section struts. The forward portion embodied plywood reinforcing-webs, and the rear portion was wire-braced throughout with plywood webs applied to the two rear bays. The main fuel tank was immediately behind the pilot, and the oil tank was directly above it. There was an external gravity fuel tank of 5-gallon capacity on the starboard upper wing. The undercarriage was a plain vee structure with two steel tube spreader bars and rubber cord shock absorbers.
  The mainplanes had two wooden spars, spindled out for lightness, connected by steel tube compression struts and cross-braced by steel wire. Single-bay interplane bracing was used, and both landing and flying wires were single. The tail-unit was of wooden construction, with steel tube forward edges on rudder and elevators. The rudder of the prototype was horn-balanced; but a plain rudder was fitted to production D.H.5s, and the size of the vertical tail surfaces was slightly increased. The standard engine was the 110 h.p. Le Rhone, but there are indications that an experimental installation of the 110 h.p. Clerget may have been made.
  The production machines began to appear in the spring of 1917, and the D.H.5s made their debut in France in May of that year. No. 24 Squadron received its first D.H.5 on May 1st, and No. 32 Squadron began to re-equip with the type at about the same time. Both units had been flying D.H.2s, and still had one or two of their faithful little pushers on June 7th. The F.E.8s of No. 41 Squadron were replaced by D.H.5s in July, 1917; No. 68 (Australian) Squadron went to France with D.H.5s on September 21st; and No. 64 followed, similarly equipped, on October 15th.
  In 1917, an aeroplane with the radical appearance of the D.H.5 could not fail to give rise to a host of extraordinary rumours. In the case of the D.H.5 these centred around its stalling characteristics. It must be admitted that the machine’s behaviour at the stall was not all it might have been, and much play was made with the theory that the lower wing blanketed the upper by virtue of their relative positions and thereby made recovery difficult. There was, however, no foundation for the rumour that the D.H.5 stalled at 80 m.p.h., viciously and without warning.
  One pilot has recorded that, when he was ordered to take a D.H.5 on a delivery flight, he was warned not to try to fly it at less than 90 m.p.h. Soon after take-off he found himself in difficulties owing to engine trouble, but he was relieved to find that the machine’s stalling characteristics had been greatly exaggerated, and that it was “a most comfortable and pleasant machine to fly, extremely sensitive to aileron control.” The D.H.5’s ailerons were large and of high aspect-ratio.
  The machine was highly manoeuvrable and capable of all the normal aerobatics, but it never achieved popularity. A number of accidents which occurred with D.H.5s at training aerodromes did little to make it more popular, and several of these were attributed to a tendency for elevator control to diminish dangerously near the stall.
  The first D.H.5 to go to France did so late in 1916, presumably for Service trials; but the type did not begin to be operational until the end of May, 1917. On the 25th of that month, Second Lieutenant S. Cockerell of No. 24 Squadron scored the first victory by a D.H.5 of his squadron. Combat successes did not come easily to the D.H.5, and in 205 combats between May 25th and December 25th, 1917, No. 24 Squadron could claim only three enemy machines as completely destroyed, whereas in the 774 combats fought by the squadron when equipped with the D.H.2 no fewer than forty-four enemy machines were destroyed.
  The D.H.5 was not at its best above 10,000 feet, and it was found that when, as in November, 1917, it was necessary to send out mixed formations, these had to be arranged in layers with the D.H.5s at the lowest level. A typical arrangement was for Sopwith Pups to be at 15,000 feet, Bristol Fighters at 12,000 feet, and D.H.5S at 9,000 feet; and the fact that the D.H.5 was inferior to the earlier Pup in ability to hold its height in combat did not improve its reputation with its pilots.
  It is as a ground-attack aeroplane that the D.H.5's best remembered. It was peculiarly well suited to this hazardous duty, for it was strong and from its cockpit the pilot had an unusually good forward view. The first organised use of D.H.5s for ground-strafing occurred during the Battles of Ypres. On August 16th, 1917, two D.H.5s were allotted to each divisional front for cooperation with the forward infantry. One week earlier, the D.H.5s of No. 41 Squadron had demonstrated the use of the type on ground-attack work when they greatly assisted an infantry assault opposite Boiry Notre Dame by attacking enemy trenches, machine-gun emplacements, and trench-mortar positions.
  The Battle of Cambrai again saw the D.H.5 used on ground-strafing duties. These were so much accepted as part of the D.H.s’s normal work that No. 64 Squadron had practised much low-flying before going overseas, and after the arrival of the unit in France low-flying in formation was practised. By this time (November, 1917), the D.H.5s were carrying four 25-lb bombs, and No. 64 Squadron and No. 68 (Australian) Squadron did a considerable amount of low-level bombing and strafing during the battle.
  Cambrai virtually marked the end of the D.H.5s operational career, for all the squadrons using the type were re-equipped with S.E.5a’s by the end of January, 1918. Its Service life was brief, even by the standards of the First World War, and it did not long survive at training aerodromes.
  The D.H.5 was used only on the Western Front. However, the experimental arrangement of the armament on A.9186 may have indicated an intention to use the machine on Home Defence duties: in this D.H.5 the Vickers gun was inclined upwards at about 45° and fired above the airscrew. In fact, no D.H.5s were issued to Home Defence units.
  The type was a bold experiment which deserved greater success than it achieved, but its unpopularity and brief career combined to make it one of the less well-known machines of its time.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: The Darracq Motor Engineering Co., Ltd., Townmead Road, Fulham, London, S.W.6.
March, Jones and Cribb, Leeds. British Cauldron Co., Ltd., Broadway, Cricklewood, London, N.W.2.
  Power: 110 h.p. Le Rhone; 110 h.p. Clerget.
  Dimensions: Span: 25 ft 8 in. Length: 22 ft. Height: 9 ft 1 1/2 in. Chord: 4 ft 6 in. Gap: 5 ft. Stagger (negative): 2 ft 3 in. Dihedral: 4° 30'. Incidence: 2° (2° 15' at port interplane struts). Span of tail: 8 ft 4 1/2 in. Wheel track: 5 ft. Tyres: 700 X 75 mm. Airscrew diameter: 8 ft 6 1/2 in.
  Areas: Wings: upper 111-2 sq ft, lower 100-9 sq ft. total 212-1 sq ft. Ailerons: each 11-6 sq ft, total 46-4 sq ft. Tailplane: 13-4 sq ft. Elevators: 12-2 sq ft. Fin: 2-2 sq ft. Rudder: 6-3 sqft.
  Tankage: Petrol: main (pressure) tank, 21 gallons; gravity tank, 5 gallons; total, 26 gallons. Oil: 4 gallons.
  Armament: One fixed forward-firing Vickers machine-gun mounted on top of fuselage to port of centre and synchronised by Constantinesco C.C. Gear. Four 25-lb bombs could be carried on racks under the fuselage.
  Service Use: Western Front: R.F.C. Squadrons Nos. 24, 32, 41, 64 and 68 (Australian). Training: Schools of Aerial Fighting at Turnberry, Marske, Sedgeford and Freiston. Advanced Air Firing School, Lympne. London Colney.
Production and Allocation: At least 550 D.H.5S were built. A total of 483 went into service with the R.F.C.: of that number, 341 went to the Expeditionary Force in France, and 142 went to Training Units. Presumably the remaining sixty-seven were in store.

Serial Numbers:
Serial Nos. Contractor
A.5172 Aircraft Manufacturing Co.
A.9163-A.9361 Aircraft Manufacturing Co.
A.9363-A.9562 Darracq Motor Engineering Co.
B.331-B.380 British Cauldron Co., Ltd.
B.4901-B.5000 March, Jones and Cribb
B.7775 No. 1 (Southern) Aeroplane Repair Depot

  Notes on Individual Machines: Used by No. 24 Squadron: A.9165, A.9166, A.9167, A.9175, A.9176, A.9178, A.9182,
9183, A.9220, A.9241, A.9272, A.9291, A.9329, A.9363, A.9435 (“E”), A.9448, A.9471, A.9496, A.9514,
334, B.341, B.348, B.349, B.359. Used by No. 32 Squadron: A.9179, A.9207, A.9300, A.9311, A.9315, A.9340 (“C”), A.9374, A.9404, A.9422, A.9431, A.9439, B.345, B.4914, B.4916, B.4924. Used by No. 41 Squadron: A.9168, A.9196, A.9208, A.9218, A.9225, A.9408, A.9410, A.9440, A.9444, B.340. Used by No. 64 Squadron: A.9458, A.9507 (“E”). Used by No. 68 (Australian) Squadron: A.9224, A.9226, A.9242, A.9245, A.9263, A.9265, A.9271, A.9273, A.9283, A.9284, A.9288, A.9459, A.9462, A.9464, A.9469, A.9473, B.377. Other machines: A.9186: experimental armament - Vickers gun inclined upwards at 45°. A.9242: “Australia No. 15, N.S.W. No. 14, The Women’s Battleplane”. A.9357: “Tacati”. A.9414: “Dungarpur”. A.9415: “Australia No. 8, N.S.W. No. 7, Government”. A.g432: “Australia No. 16, N.S.W. No. 15, Government”. A.9513: “Benin”. B.371: “Solanki”.
Weights (lb) and Performance:
Prototype Production
No. of Trial Report M.76 M.117
Date of Trial Report December, 1916 July, 1917
Type of airscrew used on trial - L.P. 1708
Weight empty 1,006 1,010
Military load 80 80
Pilot 180 180
Fuel and oil 220 222
Weight loaded 1,486 1,492
Maximum speed (m.p.h.) at
3,020 ft 110 -
4,800 ft 108 -
6,600 ft 104 -
8,660 ft 102 -
10,000 ft - 102
10,250 ft 100 -
12,350 ft 98 -
13,000 ft - 94-5
14,100 ft 95 -
15,000 ft - 89
m. s. m. s.
Climb to
1,000 ft 1 00 0 50
2,000 ft 2 00 - -
3,000 ft 3 06 - -
4,000 ft 4 18 - -
5,000 ft 5 42 - -
6,000 ft 7 24 - -
6,500 ft 8 24 6 55
7,000 ft 9 24 - -
8,000 ft 11 36 - -
9,000 ft 14 00 - -
10,000 ft 16 18 12 25
11,000 ft 18 48 - -
12,000 ft 22 00 16 40
13,000 ft 27 00 - -
14,000 ft 33 00 22 50
14,300 ft 36 00 - -
15,000 ft - - 27 30
Service ceiling (feet) 14,000 16,000
Endurance (hours) 3 2 3/4

Costs:
   Airframe without engine, instruments and gun £874 os.
   110 h.p. Le Rhone engine £771 10s.

de Havilland 6

  TOWARDS the end of 1916 it was realised that training aeroplanes must be available in substantial numbers if the expansion of the R.F.C. were to continue. The immediate need was for a machine which would have safe flying characteristics, would be quickly and easily produced, and would likewise be quickly and easily repaired. To meet this requirement, Captain de Havilland designed the D.H.6. The aeroplane was a two-seat tractor biplane, and was remarkable for its almost primitive disregard for aerodynamic refinements of any kind. Structural simplicity was achieved almost to an extreme, and popular legend of the day had it that the square-cut wings were “made by the mile and cut off by the yard”. The fin and rudder were originally of typical de Havilland outline, but even these were replaced by rectilineal surfaces in the production machines.
  The fuselage was made in two parts, which were joined by fish-plates just behind the long communal cockpit. The front portion was covered with plywood, and the rear portion was a conventional wooden box-girder with wire cross-bracing. Production D.H.6s had a flat top-decking; on the prototype it was rounded. The tail surfaces were formed of steel tubing, and the undercarriage was a sturdy vee structure with two steel tube spreader bars between which the axle lay; shock absorption was by rubber cord.
  The square-ended wings were entirely conventional in construction, and upper and lower wings were interchangeable. A very heavily cambered aerofoil section was used, and the concavity of the undersurface was pronounced. This feature earned the D.H.6 the nickname of “The Clutching Hand”, and the tall exhaust stacks are usually regarded as responsible for the machine’s other soubriquet of “The Sky Hook”; but the D.H.6’s unhurried progress may also have had something to do with the latter name. The peculiar long undivided cockpit earned the D.H.6 the two lesser-known but picturesquely uncomplimentary nicknames of “The Flying Coffin” and “The Dung-hunter”. The reason for the former is obvious; the latter was bestowed by the Australians because the large cockpit bore an alleged resemblance to a certain type of farm vehicle. In more polite R.F.C. colloquy the type was frequently referred to as “The Sixty”, and occasionally as “The Crab” or “The Clockwork Mouse”.
  The standard engine for the D.H.6 was the 90 h.p. R.A.F. ta, but considerable numbers were also built with the 90 h.p. Curtiss OX-5 engine. The wings of the Curtiss-powered machines were rigged with negative stagger. When supplies of these engines ran short the 80 h.p. Renault was substituted. The first production contract for 700 D.H.6s was placed on January 13 th, 1917, with the Grahame-White Aviation Co., and by the end of the following June, thirty-seven had been delivered.
  The D.H.6 was widely used on training duties at home, in the Middle East, and in Australia. In this work its very indifferent performance mattered little, and its complete lack of vices made it a safe elementary trainer. It was, in fact, almost too safe, for it could be flown with little regard to air speed, had an innocuous stall, and was virtually unspinnable. Towards the end of 1917, the Avro 504K was adopted as the R.F.C.’s standard trainer, and production of the D.H.6 was thereafter tapered off.
  At about this time the depredations of U-boats among Allied merchant ships reached alarming proportions. A remarkable fact was that the number of ships sunk at a distance of less than ten miles from land rose steadily until it represented 60 per cent of the total number of sinkings. At the end of January, 1918, the Commander-in-Chief of the Grand Fleet asked for additional aircraft to patrol coastal waters between the Tyne and the Tees: this area was one of particular danger.
  As a temporary expedient the Air Ministry placed two Flights of D.H.6s and two of F.E.2b’s at the disposal of the Admiralty early in March; both D.H.6 Flights were stationed at Cramlington. So far from being a mere stop-gap, the D.H.6 remained in service as an anti-submarine aircraft until the Armistice, and its use in that capacity was greatly extended in June, 1918. By this time the D.H.6 was being withdrawn from training duties, and some 300 were surplus to requirements. The Air Ministry offered to provide the Admiralty with thirty-two further Flights of D.H.6s, a total of 192 aircraft, for antisubmarine patrol. The Admiralty accepted this offer. Twenty-seven of the Flights were established at various coastal aerodromes, and the remaining five Flights of D.H.6s were operated by the U.S. Naval Air Service for patrols off the Irish coast. (American personnel were available but had no aeroplanes to fly at that time.)
  The anti-submarine D.H.6s operated under appalling conditions, and much hardship was endured by the men who flew and serviced them. Most of the crews were men who were no longer fit for operational duties, but they were always overworked because the Flights were never up to strength. On patrol, the D.H.6 was almost always flown solo, for it was incapable of lifting both an observer and a load of bombs; but about one machine in four was used as a two-seater for convoy work, which necessitated the presence of an observer who could use an Aldis lamp.
  In an attempt to improve performance, after March 14th, 1918, the D.H.6s still in service were rigged with a backward stagger of 10 inches, and the aerofoil section was modified to have much less undercamber. At about this time new elevators and a new rudder, all of reduced chord, were fitted. These modifications added a few miles per hour to the maximum speed, but did nothing to improve the machine’s weight-lifting capabilities. Flotation gear was installed on at least one Curtiss-powered D.H.6, and the aircraft was tested in November, 1918.
  At best, the use of the D.H.6s as anti-submarine aircraft was mere bluff, based on the theory that submarine commanders would not surface nor use their periscopes in areas known to be patrolled by aeroplanes. However, the machines had their moments of action. On May 30th, 1918, a coastal D.H.6 bombed the submarine U.C.49 a few moments after it had torpedoed the S.S. Dungeness; the U-boat crash-dived and escaped.
  After the Armistice a considerable number of D.H.6s came on to the British Civil Register, and others pioneered air transport in the Empire, notably in Australia and South Africa. A D.H.6 was reported to be still in existence at Geelong West, Victoria, as late as 1937.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: The Grahame-White Aviation Co., Ltd., Hendon, London, N.W.; The Gloucestershire Aircraft Co., Ltd., Cheltenham; Harland & Wolff, Ltd., Belfast; The Kingsbury Aviation Co., Kingsbury; Morgan & Co., Leighton Buzzard; Ransome, Sims & Jeffries, Ipswich; Savages, Ltd., Stroud. Power: 90 h.p. R.A.F. ia; 90 h.p. Curtiss OX-5; 80 h.p. Renault.
  Dimensions: Span: 35 ft 11 1/8 in. Length: 27 ft 3 1/2 in. Height: 10 ft 9 1/2 in. Chord: 6 ft 4 in. Gap: 5 ft 8 1/2 in. Stagger: originally nil, later 10 in. backwards. Dihedral: 2°. Incidence: 4°. Span of tail: 12 ft. Wheel track: 5 ft 7 3/16 in. Airscrew diameter: 9 ft 2 in. (with R.A.F. 1a engine).
  Areas: Wings: upper 224-3 sq ft, lower 212 sq ft, total 436-3 sq ft. Ailerons: each 19 sq ft, total 76 sq ft. Tailplane: 36 sq ft. Elevators: 26 sq ft. Fin: 5-5 sq ft. Rudder: 12 sq ft.

  Weights (lb) and Performance:
Engine R.A.F.1a Curtiss Curtiss with flotation gear
No. of Trial Report - N.M.239 N.M.239
Date of Trial Report - November 12th, 1918 November 12th, 1918
Type of airscrew used on trial - A.D.543 A.D.543
Weight empty 1,460 1,539 1,624
Military load Nil Nil Nil
Crew 360 180 180
Fuel and oil 207 207 207
Weight loaded 2,027 1,926 2,011
Maximum speed (m.p.h.) at
2,000 ft - 75 72-5
6,500 ft 66 - -
m. s. m. s. m. s.
Climb to 6,500 ft 29 00 35 00 45 00
Service ceiling (feet) - 6,100 5.400

  Tankage: Petrol: 25 gallons. Oil: 4 gallons.
  Armament: When used for anti-submarine patrol, one 100-lb bomb or a roughly equivalent weight of smaller bombs was carried.
  Service Use: Widely used at training aerodromes in the United Kingdom, e.g. No. 1 Training Depot Squadron, Stamford; No. 39 Training Squadron, Narborough; No. 42 Training Squadron, Hounslow; No. 44 Training Squadron, Waddington. Home Defence: No. 77 Squadron. Middle East: 20th Training Wing, Abu Qir. Australia: Central Flying School, Point Cook, Werribee, Victoria. For anti-submarine patrols: Tyne, two Flights at Cramlington; Humber to Tees, five Flights; Tees to St Abbs Head, four Flights (e.g. at Tynemouth, Sea Houses and Elford); Portsmouth Group, four Flights; South Western area, eight Flights (including No. 250 Squadron at Padstow); Irish Sea, six Flights; Ireland, five Flights operated by U.S. Naval Air Service.

  Serial Numbers:
Serial Nos. Contractor Contract No. |
A.5175-A.5176 Aircraft Manufacturing Co. -
A.9563-A.9762 Grahame-White Aviation Co. 87/A/1359
B.2601-B.3100 Aircraft Manufacturing Co. 87/A/1844
B.9031-B.9130 Aircraft Manufacturing Co. A.s.17567
C.1951-C.2150 Grahame-White Aviation Co. 87/A/1359
C.5126-C.5275 Kingsbury Aviation Co. A.S.22909
C.5451-C.5750 Harland & Wolff A.S.19062
C.6501-C.6700 Morgan & Co. A.S.20465
C.6801-C.6900 Savages A.S. 19896
C.7201-C.7600 Ransome, Sims & Jeffries A.S. 18918
C.7601-C.7900 Grahame-White Aviation Co; 87/A/1359
C.9336-C.9485 Gloucestershire Aircraft Co. A.S.32956
D.951-D.1000 Grahame-White Aviation Co. A.S.32667
D.8581-D.8780 Aircraft Manufacturing Co. -

  Production and Allocation: Contracts were placed for a total of 2,850 D.H.6s. A total of 2,282 were completed, and 1,754 of those were distributed to R.F.C. and R.A.F. units. Training units received 1,531; Home Defence units received seventy-one in 1918; and 152 went to the Middle East. The R.A.F. had 1,050 D.H.6s on charge on October 31st, 1918. Of these, sixty-nine were in Egypt and forty were en route to the Middle East; thirty-three were at schools in the U.K. and a similar number with Home Defence units; eight were in Ireland; 594 were at various aerodromes; five were at Aeroplane Repair Depots, two with contractors, and the remaining 266 were in store.
  Costs:
   Airframe without engine and instruments,
   (i) for R.A.F. 1a £841 10s.
   (ii) for Curtiss £885 10s.
   Engines: R.A.F. la £522 10s.
   Curtiss OX-5 £693 10s.

de Havilland 9

  ON June 13th, 1917, German bombers attacked London in daylight and inflicted casualties which exceeded those caused within the County of London by all the Zeppelin attacks made up to that time. A few hours after the raid, Sir William Robertson, the Chief of the Imperial General Staff, asked for a substantial increase in the number of British aeroplanes. The German raid was proof enough of the potentiality of the aeroplane as a weapon of offence, and of the need for adequate means of defence; and the Cabinet agreed with Sir William Robertson that more British aircraft were urgently needed.
  At a meeting held at the War Office on June 21st, 1917, it was decided to increase the service squadrons of the R.F.C. from 108 to 200; the majority of the new squadrons were to be equipped with bombing aircraft. Seven hundred D.H.4s were ordered at the end of June, 1917, for the equipment of the new bombing squadrons, and Sir Douglas Haig was told that development of a machine with longer range than the D.H.4 would be undertaken in order to permit the ultimate extension of the area of bombing operations.
  On July 23rd, 1917, the Controller of Technical Design laid before the Air Board plans of an extensively modified version of the D.H.4 which, it was claimed, would have a speed of 112 m.p.h. at 10,000 feet and a greater range. The modifications were so extensive that the machine had to be regarded as a new type, and was given the type number D.H.9. The Air Board did not immediately decide to abandon the well-tried D.H.4, but, at their next meeting three days later, an assurance was given that the adoption of the new design would delay production by no more than three or four weeks. It was therefore decided to substitute the D.H.9 for the D.H.4 in the contracts which had already been let with contractors.
  The prototype D.H.9 was A.7559, a modified D.H.4, and was flying in July, 1917. The engine was the 230 h.p. Galloway-built B.H.P., sometimes referred to as the Galloway Adriatic. This was the B.H.P. engine in its original form. The official choice fell upon the B.H.P. engine for the D.H.9’s power plant because it had been selected for very large scale production. Mass production of the 230 h.p. B.H.P. engine was made the special responsibility of the Siddeley-Deasy Car Co., who were then building some twenty-five to thirty standard B.H.P.s per week. Two thousand engines were ordered from Siddeley-Deasy. Delays occurred before modifications could be made to facilitate quantity production, and a major difficulty arose from the production of the aluminium cylinder blocks. Enough cylinder blocks were available by July, 1917, to permit production of the engines at the rate of too per month, but it was soon found that more than 90 per cent of the cylinder blocks were defective. The modified engine had been named the Siddeley Puma and the first few were rated at 300 h.p., but these gave so much trouble owing to faulty cylinder blocks that the engine was de-rated to 230 h.p. Perhaps the original output of 300 h.p. was responsible for the first optimistic estimates of the D.H.9’s performance.
  That these estimates would not be realised was known before the D.H.9 came into service. This information reached Major-General H. M. Trenchard in November, 1917, and on the 16th of that month he wrote to Major-General J. M. Salmond, then Director-General of Military Aeronautics, to say that he had learned unofficially from Mr Geoffrey de Havilland that the performance of the D.H.9 would be poorer than that of the Rolls-Royce-powered D.H.4, and that the new machine would be unable to reach 15,000 feet fully loaded. Major-General Trenchard went on: “I do not know who is responsible for deciding upon the D.H.9, but I should have thought that no-one would imagine we should be able to carry out long-distance bombing raids by day next year with machines inferior in performance to those we use for this purpose at present. I consider the situation critical. ... I am strongly of opinion that unless something is done at once we shall be in a very serious situation next year. ...” Major-General Salmond placed these representations before the Air Board, but was informed by Sir William Weir that the choice was between the B.H.P.-powered D.H.9 or nothing at all.
  On November 14th Sir Douglas Haig, inspired by Major-General Trenchard, had asked for orders for D.H.9s to be reduced to limit their use to no more than fifteen squadrons, because the type would be outclassed as a day bomber by June, 1918.
  But it was too late. As with the B.E.2c and 2e earlier in the war, the official decision had been taken to standardise the D.H.9, and production was too far advanced for a change to be made. Ultimately, production of the Siddeley Puma engine reached 200 per week, and D.H.9s were turned out at the rate of one every forty minutes.
  The squadrons who had to fly the type had to make the best of a bad job, and there was a world of truth in the wry description of the D.H.9 as a “D.H.4. which has been officially interfered with in order to be suitable for mass-production and the B.H.P. motor”.
  In construction the D.H.9 was identical to the D.H.4: indeed, the wings and tail unit were the same in every respect. The most obvious external differences between the D.H.9 and D.H.4 lay in the engine installation and the disposition of the cockpits. The later machine made a breakaway from contemporary British practice by having a retractable radiator placed under the fuselage instead of arranged round the airscrew shaft. The cowling of the engine gave the nose of the D.H.9 a “Hunnish” appearance, but the cylinders and exhaust manifold formed an inelegant excrescence. The revised cockpit arrangement was probably the only improvement over the D.H.4: pilot and observer were close together and were able to communicate instantly and easily with each other. The pilot was also spared the unenviable position he occupied in the D.H.4, between the engine and fuel tanks. Nevertheless, the farther aft position of the pilot gave rise to criticism because the forward and downward view was obscured by the lower wing. To improve matters a cut-out was made in the root of the lower starboard wing between the spars. The D.H.9’s gravity fuel tank was contained in the centre-section, between the spars.
  The D.H.9 was, in short, a good aeroplane spoiled by a bad engine which, if the truth be told, was obsolete at the time it was adopted as the power unit. With the B.H.P. engine the D.H.9 was expected to lift a greater load than the more powerful D.H.4, and in doing so its ceiling and performance suffered so severely that it was an easy victim for the German fighting scouts, particularly when engine failure on several machines reduced the numbers of a formation and robbed it of some of its defensive fire-power. The D.H.9 was unable to maintain its height with full load at 15,000 feet, and was seldom able to fly above 13,000 feet. It was therefore at a severe tactical disadvantage.
  The first production D.H.9s were completed late in 1917: five were delivered before the end of the year. The early machines had B.H.P. engines built by both the Galloway and Siddeley-Deasy concerns. The type was issued to the squadrons early in 1918. The first D.H.9s in France were those of Squadrons Nos. 98, 206 and 211, all of which were in France at the beginning of April, 1918. Nos. 98 and 206 were with the II Brigade, and participated in the Battle of the Lys. On April 12th, nineteen pilots of No. 206 Squadron flew a total of 76 hours, and on that day No. 98 mounted no less than six sorties.
  The name of the D.H.9, like that of the Handley Page O/400, will probably be forever linked with that of the Independent Force. In May, 1918, Squadrons Nos. 99 and 104 joined the VIII Brigade, the forerunner of the Independent Force: No. 99 arrived in France on May 3rd, No. 104 on May 19th. The squadrons supplemented the work of the D.H.4s of No. 55 Squadron, and made their first raids on May 21 st and June 8th respectively. These two units carried out eighty-three raids before the Armistice. That total represented 848 machine-sorties: of these, no fewer than 123 had to return with engine trouble. During the period, No. 99 Squadron lost twenty-one D.H.9s and 104 Squadron thirty-three to enemy action, and a further ninety-four machines were otherwise wrecked.
  The D.H.9’s operational showing did nothing to enhance Major-General Trenchard’s opinion of it. His prophecy that the machine would be outclassed by June, 1918, was soon fulfilled; and writing in that month he said it was imperative that every effort should be made to replace the D.H.9 by tbe Liberty-powered D.H.9A. By the end of August, 1918, Major-General Trenchard decided that the D.H.9 could no longer be regarded as a front-line type: the losses which must be expected from the continued use of the type did not justify sending the D.H.9 squadrons over the lines.
  In his report on the work of the R.A.F. on the Western Front during October, 1918, Major-General J. M. Salmond said of the D.H.9 "... although this type of aeroplane has sufficient petrol, and oil, to enable it to reach objectives too miles from the lines, its low ceiling and inferior performance oblige it to accept battle when, and where, the defending forces choose, with the practical result that raids tend to become restricted to those areas within which protection can be afforded by the daily offensive patrols of scout squadrons....”
  Of the melancholy events which inspired Major-General Salmond’s report, none was worse than the experience of No. 99 Squadron on July 31st, 1918. Twelve D.H.9s of the squadron set out at 5.30 a.m. that morning to attack Mainz but, true to form, engine trouble forced three of the formation to return. Over Saaralbe, enemy scouts attacked and shot down one D.H.9, and a subsequent onslaught by about forty enemy machines near Saarbrucken shot down three more D.H.gs. The five survivors battled on as far as Saarbrucken and dropped their bombs on the railway station; but the enemy fighters maintained their attack and another D.H.9 crashed near the centre of the town. Two more fell on the homeward journey: only the leader, Captain A. H. Taylor, and one other pilot brought their D.H.9s back to No. 99’s aerodrome at Azelot.
  The enemy did not escape scot free. Part of Captain Taylor’s report reads: “We also accounted for eight enemy scouts definitely known to have crashed. ... We lost seven machines. ... I recommend that we return and finish the job.” But the squadron had lost fourteen experienced officers, and was unable to resume its work until the replacements had been adequately trained in formation flying.
  Despite Major-General Trenchard’s decision of late August, the D.H.9 remained operational until the Armistice; indeed, so persistent were those in authority that it replaced the superior D.H.4 in several squadrons. Until the end, however, the D.H.4 was treated with greater respect than the D.H.9 by the enemy fighters. To the last, the D.H.9s were let down by their engines: on October 1st, 1918, of twenty-nine D.H.9s sent by Nos. 27 and 98 Squadrons to bomb the railway junction at Aulnoye, no fewer than fifteen had to turn back with engine trouble, and the depleted formation was unable to attack its objective.
  On other fronts D.H.9s played a rather more successful part in achieving victory. In Palestine, those of No. 144 Squadron took part in the sustained attacks on the retreating Turks, on September 19th, 1918, on the Tul Karm-Nablus road, and two days later in the Wadi el Far‘a. On September 23rd, the attacks made by the D.H.9s on Mafraq station and on enemy columns on the Es Salt-‘Amman road helped to hasten the defeat of the Turks.
  In Macedonia, No. 47 Squadron received its first D.H.9 on August 2nd, 1918, and “A” Flight of that unit was completely equipped with the type by August 21st, 1918. No. 17 Squadron similarly received a Flight in September, and each squadron had six D.H.9s at the time of the Armistice. The new aircraft made long-range reconnaissances possible, and frequently carried out flights of 300 miles. Between September 1st and 29th, the D.H.9s of No. 47 Squadron flew a total of 315 1/2 hours. In this theatre of war the D.H.9 was, in fact, used more for reconnaissance work than for bombing, but on September 21st the D.H.9s participated in the attacks on the retreating Bulgarian army caught in the Kosturino Pass.
  The D.H.9s operating from the Aegean islands made serious attempts to bomb Constantinople by night and day: the flight was one of about 440 miles and took some 5 1/2 hours. The machines were fitted with “home-made” extra fuel tanks which increased their endurance to 5 3/4 hours. Thus, the margin of safety was so narrow that many of the D.H.9s failed to reach their home aerodromes, and landings were perforce made elsewhere, occasionally in the sea.
  Coastal aerodromes in the United Kingdom received the D.H.9 in 1918 for anti-Zeppelin work and for escorting the big flying boats. One of the D.H.9s from Great Yarmouth air station (No. 212 Squadron, R.A.F.) attacked the Zeppelin L.65 on the night of August 5th/6th, 1918. It did not succeed in destroying the airship, but was itself lost in mysterious circumstances. Towards the end of the war, D.H.9s began to replace D.H.6s for anti-submarine patrols.
  Since the B.H.P. engine was so unreliable, it is regrettable that history does not tell more about the D.H.9s which had the 250 h.p. Fiat A-12 engine. Two thousand engines of this type had been ordered in August, 1917, at the instigation of Sir William Weir. The contract stipulated that deliveries were to be made between January and June, 1918, and it was intended to allocate 1,000 engines to America and to use the other thousand in D.H.9s. Only a tenth of that number were so used, however: early installations of the Fiat were made in the D.H.9s numbered C.6052 and D.5748, and 100 Fiat-powered machines (numbered D.2776-D.2785) were ordered from Short Brothers.
  The Fiat A-12 was a six-cylinder in-line engine, and its similarity in configuration to the B.H.P. resulted in a generally similar installation. The Fiat could be distinguished by its exhaust manifold on the starboard side; that of the B.H.P. was on the port.
  In October, 1918, a D.H.9 was tested with the high-compression version of the Siddeley Puma, which gave 290 h.p. This engine made no appreciable improvement in the aircraft’s performance, however.
  In the summer of 1917 the firm of D. Napier & Son designed an aero-engine of unusual configuration: it was a twelve-cylinder engine with cylinders arranged in three groups of four, which were disposed in the form of a broad arrow. At first this engine was known as the Napier Triple-Four, and in September, 1917, the manufacturers envisaged a power output of 300 b.h.p. at 10,000 feet.
  The new engine was named the Napier Lion, and early in 1918 one of the prototype Lions was installed in the D.H.9 numbered C.6078. Early trials at Farnborough showed that the heating of the induction system was inadequate. The application of hot-water jackets and lagging to the induction pipes, of water jackets to the carburettor throttles, and of exhaust-heated jackets to the air intakes, proved to be of little use.
  Development proceeded and, after the initial difficulties had been overcome, it became evident that the Lion was an excellent engine and one which would have been of great benefit to the D.H.9. By June, 1918, the Lion-Nine was returning good performance figures, and shortly afterwards C.6078 was fitted with the first production Napier Lion engine. The airframe was strengthened in several ways: at the forward end of the fuselage additional three-ply webs were fitted and steel plates were applied to crossmembers; at the tail the bottom longerons were reinforced by ash strips; the front spar of the tailplane was reinforced, and steel tube bracing struts were fitted; and thicker plywood was applied to the centresection. The retractable radiator was increased in size.
  With this engine the D.H.9 at last had a worthwhile performance. It was delivered to Martlesham Heath for service trials at the beginning of October, 1918. While there the machine was flown by Captain Andrew Lang to a height of 30,500 feet, a new world’s record at the time. The climb was made on January 2nd, 1919, and occupied 66 minutes 15 seconds. Lang’s observer was Lieutenant Blowes.
  The American Expeditionary Force bought two D.H.9s in July, 1918. These machines were delivered without engines, and were used to test the installation of the 400 h.p. Liberty 12-A engine in the airframe. One went to America, for it was intended to produce the type there, powered by the Liberty engine. The projected scale of American manufacture made even the highly creditable rate of British production look somewhat amateurish, for no fewer than 14,000 aircraft were ordered. In October, 1918, four D.H.9s were in service with the U.S. Naval Northern Bombing Group in France, but it is uncertain whether they were American-built machines. An American-designed development of the D.H.9 was built under the designation USD-9. Four USD-9s were delivered in August, 1918: two were built by Dayton-Wright and two by the Engineering Division of the Bureau of Aircraft Production. All contracts were cancelled after the Armistice.
  In 1918 eighteen D.H.9s were supplied to the Belgian Flying Corps, presumably for use as day bombers.
  The D.H.9 remained on active service with the R.A.F. after the Armistice. In Russia, Nos. 47 and 221 Squadrons were equipped with a mixture of D.H.9s and D.H.9As for service with Denikin’s White Army in 1919. So intense was the cold that water had to be boiled and oil heated before the radiators and sumps of the aircraft could be filled. One captured machine was operated by the Reds towards the end of the campaign.
  After the war the D.H.9 was used for a few years by the R.A.F., but was withdrawn in favour of the superior D.H.9A. It took some time for the D.H.9s to be disposed of, but other nations took advantage of the low price at which the Aircraft Disposals Co. sold the discarded machines.
  The D.H.9 did a vast amount of pioneering work in the field of commercial aviation, and several modified versions appeared in the post-war years. The type was used for experimental purposes with Handley Page slots and in Sir Alan Cobham’s early experiments in flight refuelling. Some of the Commonwealth countries used D.H.9s, and those of the South African Air Force survived until 1937 in a much modified form known as the Mpala, which was powered by a Bristol Jupiter radial engine.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: The Alliance Aeroplane Co., Ltd., Cambridge Road, Hammersmith, London; F. W. Berwick & Co., Ltd., Park Royal, London, N.W. 10; Cubitt, Ltd., Croydon; Mann, Egerton & Co., Ltd., Aircraft Works, Norwich; National Aircraft Factory No. 1, Waddon; National Aircraft Factory No. 2, Heaton Chapel, near Stockport; Short Brothers, Rochester, Kent; The Vulcan Motor & Engineering Co. (1906), Ltd., Crossens, Southport; Waring & Gillow, Ltd., Cambridge Road, Hammersmith, London (and Wells Aviation Co., Ltd., 30 Whitehead’s Grove, Chelsea, London, S.W.8, under sub-contract); G. & J. Weir, Ltd., Cathcart, Glasgow; Westland Aircraft Works, Yeovil, Somerset; Whitehead Aircraft Co., Ltd., Old Drill Hall, Townshend Road, Richmond.
  Power: 230 h.p. B.H.P. (Galloway Adriatic); 230 h.p. Siddeley Puma; 290 h.p. Siddeley Puma (high compression) ; 250 h.p. Fiat A-12; 430 h.p. Napier Lion; 400 h.p. Liberty 12-A.
  Dimensions: Span: 42 ft 4 5/8 in. Length (B.H.P. and Puma): 30 ft 6 in., (Lion) 30 ft 9 1/2 in., (Liberty) 30 ft. Height: 11 ft 2 in. (with Lion, 11 ft 7 3/4 in.). Chord: 5 ft 6 in. Gap: 5 ft 6 in. Stagger: 12 in. Dihedral: 3. Incidence: 3. Span of tail: 14 ft. Wheel track: 6 ft. Tyres: 750 X 125 mm. Airscrew diameter: four-bladed, 8 ft 9 in.; two-bladed, 9 ft 6 1/2 in.; Napier Lion, 11 ft.
  Areas: Wings: upper 223 sq ft, lower 211 sq ft, total 434 sq ft. Ailerons: each 20-5 sq ft, total 82 sq ft. Tailplane: 38 sq ft. Elevators: 24 sq ft. Fin: 5-4 sq ft. Rudder: 13-7 sq ft.
  Tankage: On the prototype D.H.9 (A.7559) fuel tanks were as follows: petrol: two tanks behind engine, 30 gallons each, one gravity tank in centre section 10 1/2 gallons; total 70 1/2 gallons. Oil: under sump (forced feed) 5 gallons. Water: 7 1/2 gallons. On production D.H.9s: petrol: two tanks behind engine, one of 34 gallons, the other of 28 gallons, one gravity tank 8 gallons; total 70 gallons. Oil: under engine crank-case (B.H.P.) 4 1/2 gallons, (Napier Lion) 7 gallons. Water: 6 1/2 gallons.
  Armament: One fixed forward-firing Vickers machine-gun mounted on top of fuselage immediately to the left of the pilot’s windscreen and synchronised by Constantinesco G.C. Gear. Loading handle: Hyland Type B. The observer had either a single Lewis machine-gun or a double-yoked pair on a Scarff ring-mounting on the rear cockpit. Bomb racks were fitted under the fuselage and under each lower wing; the bomb release-gear was of the Gledhill type. The bomb load consisted of two 230-lb bombs, three or four 112-lb bombs, or an equivalent weight of smaller bombs.
  Service Use: Western Front: R.A.F. Squadrons Nos. 27, 49, 98, 99, 103, 104, 107, 108, 202, 206, 211 and 218. Used by Belgian Flying Corps, and a few saw service with the U.S. Naval Northern Bombing Group. Sea Patrol: No. 212 Squadron, Great Yarmouth; No. 250 Squadron, Padstow; No. 273 Squadron (Flights at Govehithe and Westgate). Palestine: No. 144 Squadron. Macedonia: Nos. 17 and 47 Squadrons. Mediterranean: Nos. 224, 225, 226 and 227 Squadrons. Aegean: Nos. 220, 221, 222 and 223 Squadrons. Russia: No. 47 Squadron at Ekaterinodar, No. 221 at Petrovsk. Training: Air Observers’ Schools at Eastchurch, Manston and New Romney; School of Photography, Maps and Reconnaissance at Farnborough; Schools of Navigation and Bomb Dropping at Stonehenge, Andover and Thetford. Also used by No. 10 Training Depot Squadron, Harling Road; No. 31 Training Squadron, Wyton; and at Cranwell and Shoreham.
  Production and Allocation: By the end of 1918, a total of 3,204 D.H.9s were built. Of these 2,166 were distributed to R.A.F. units before October 31st, 1918, as follows: to squadrons with the B.E.F., 789; to the Independent Force, 144; to the squadrons of the 5th Group (for naval cooperation), fifty-two; to the Middle East Brigade, ninety-two; to the Mediterranean, 133; to training units, 956. In addition, eighteen were supplied to the Belgian Flying Corps in 1918; and America bought two without engines in July, 1918. On October 31st, 1918, the R.A.F. had 1,866 D.H.9s on charge. In France, 334 were with the B.E.F., seventy-one with the Independent Force, and four with the 5th Group. Seven were in Egypt and Palestine, twenty-one at Salonika, and seventy-eight were at Mediterranean stations; 135 were on the way to Eastern stations. At home, 184 were at training units; thirty-seven were with squadrons mobilising; 424 were at various aerodromes; one was in use for anti-submarine patrol; twenty-four were at Aeroplane Repair Depots; forty-one were with the nth Group in Ireland; 186 were with contractors; and 319 were in store.

Serial Numbers:
Serial Nos. Contractor Contract No.
A.7559 Aircraft Manufacturing Co. Converted under A.S.21273/1/17, supplied under A.S.17569
B.7581-B.7680 Westland Aircraft A.S.17570
B.9331-B.9430 Vulcan Motor & Engineering Co. 87/A/1413
C.1151-C.1450 G. & J. Weir A.S.17570
C.2151-C.2230 Berwick & Co. 87/A/1185
C.6051-G.6121
C.6123-C.6349 Aircraft Manufacturing Co. A.S.17569
D.451-D.950 Cubitt A.S.26928
D.1001-D.1500 National Aircraft Factory No. 2 A.S.32754
D.1651-D.1750 Mann, Egerton A.S. 17994
D.2776-D.2875 Short Brothers (Fiat engines) A.S.34886
D.2876-D.3274 Aircraft Manufacturing Co. A.s.17569
D.5551-D.5850 Waring & Gillow (50 machines were built by Wells Aviation Co. under sub-contract) A.S.20391
D.7201-D.7300 Westland Aircraft A.S.42381
D.7301-D.7400 Berwick & Co. A.S.37725
D.9800-D.9899 G. & J. Weir A.s.41634
E.601-E.700 Whitehead Aircraft A.S.2341
E.5435-E-5436 Aircraft Manufacturing Co. A.s.17569
E.8857-E.9056 Aircraft Manufacturing Co. 35A/4I8/C.296
F.1-F.300 National Aircraft Factory No. 1 35A/409/C.297 (only 241 completed)
F.1101-F.1300 Waring & Gillow 35A/4I6/C.295
F.1767-F.1866 Westland Aircraft A.s.19174
Between and about
H.5546 and H.5738 Alliance Aeroplane Co. -
Between and about
H.9133 and H.9340 -

Notes on Individual Machines: Used by No. 49 Squadron: C.2202, C.6114, C.6116, C.6135, C.6175, D.457, D.461, D.3052, D.5576, D.5585, D.5596, E.623. Used by No. 98 Squadron: C.2221, C.6079, C.6106, C.6108, G.6119, D.3060, D.3169. Used by No. 103 Squadron: G.1213, C.2224, D.489, D.496, D.1003, D.2857, D.2866, D.3046. Used by No. 211 Squadron: B.7603, C.6270, D.2782, D.3233. Used at No. 1 School of Navigation and Bomb Dropping, Stonehenge: C.1320, C.2171, G.6128, D.1677, D.5681. Used at Manston: D.476, D.479, D.3028, D.5672. Other machines: A.7559: prototype D.H.9, fitted with Galloway-built B.H.P. engine No. 11, W.D.15434. B.9395: “The Mackenzie Tooloombah”. G.6051: Siddeley-built B.H.P. engine No. 5019, W.D.22693. C.6052: Fiat engine. G.6078: Napier Lion engine. D.3010 and D.3015: No. 186 Development Squadron, Gosport, 1919. D.5748: Fiat engine. D.5806: No. 186 Development Squadron, Gosport. E.8888: No. 186 Development Squadron, Gosport. F.1181: presented to Canada, February, 1919. F.1222: “Australia No. 26, Queensland No. 2, The Banchory”. F.1227: “Australia No. 27, Victoria No. 2, The Murroa”. F.1255: presented to Canada, February, 1919.
  Costs:
   Airframe without engine, instruments and guns £1,473 5s.
   Siddeley Puma engine £1,089 0s.

de Havilland io and 10A, the Amiens

  PROOF that the promise of the D.H.3 of 1916 had not been forgotten was provided early in 1918, when the first D.H.10 appeared. The relationship between the two machines was at once obvious, for the D.H.10 had the same underslung fuselage and wide-track split undercarriage. It was a three-seater designed for bombing duties, and was rather larger than the D.H.3.
  The initial contract was for four prototypes. The first machine was powered by two 230 h.p. B.H.P. engines installed as pushers, thus duplicating the engine arrangement used on the earlier D.H.3, and also had two auxiliary wheels at the nose. There were cut-outs in the trailing edges of the wings to allow the airscrews to revolve. In this form the D.H.10 first flew on March 4th, 1918. Performance at an all-up weight of 6,950 lb was quite good, but it seems probable that this figure did not include an exceptionally large bomb load. An idea of using the original D.H.10 as a Home Defence aircraft seems to have been short-lived.
  More powerful engines were tried in the other prototypes. The second machine, C.8659, had two 360 h.p. Rolls-Royce Eagle VIII engines installed as tractors, each driving a two-bladed airscrew. This machine first flew on April 20th, 1918. Both prototypes had plain ailerons which extended inboard as far as the second pair of interplane struts, and on C.8659 there were, of course, no cut-outs in the trailing edges of the wings.
  The third prototype, C.8660, had two Liberty 12 engines driving two-bladed tractor airscrews. On this D.H.10 the Liberties were housed in rather massive nacelles which extended behind the trailing edges of the wings. The sweep-back of the mainplanes was slightly reduced and the ailerons were shorter than those of the first two prototypes, but a refinement was added in the shape of horn balances. With the Liberty engines the D.H.10 had an excellent performance, and it was this version which went into production. The shape of the nose was slightly modified, and the twin nosewheels were not fitted.
  The type was officially named Amiens, but, strangely, the name has not survived. The first prototype with B.H.P. engines was designated Amiens Mk. I; the second, Eagle-powered, machine was the Mk. II, and the Liberty D.H.10 was the Amiens Mk. III.
  Structurally, the D.H.10 differed little from its predecessors. The fuselage was a wooden structure: the forward portion was a plywood-covered box and the rear part was a conventional wire-braced boxgirder with fabric covering. The two parts were butt-jointed immediately behind the rear gunner’s cockpit. All longerons and spacers were of spruce. The lower centre-section was built integral with the fuselage: the spars entered the fuselage and were divided on the aircraft centre-line, where they were connected by special star-shaped brackets. The two lowest arms of these brackets held the upper ends of two oblique bracing struts which arose from the lower longerons, and the central top arm accommodated the bottom of each single centre-section strut.
  The main fuel supply was carried in two 98-gallon tanks, one of which was situated immediately behind the pilot, and the other in front of the rear gunner’s cockpit. The space between the tanks was the bomb bay. A 19-gallon gravity tank was mounted in the upper centre-section. Dual control was provided in the rear gunner’s cockpit: the rudder bar was normally concealed by two doors in the floor of the cockpit.
  The wings were conventional in construction. Spars were of laminated spruce; compression ribs were of ash three-ply with spruce capping; and the internal cross-bracing was of 2 B.A. tie rods. The aileron control cables ran inside the wings. The interplane struts were of silver spruce, and single Rafwires were used for bracing. The struts which carried the engine-bearers were of faired steel tube.
  The tailplane had spruce spars, and its incidence could be controlled from the cockpit. The elevators had steel tube trailing edges. The fin and rudder were built in similar fashion; the fixed surface was wholly made of wood, whilst the trailing edge of the rudder was of steel tubing.
  The eminently sensible undercarriage relied on rubber cord for shock absorption: 26 feet of 5/8-inch diameter cord was used on each side. The tail-skid was of steel-shod ash, and had three rubber cord springs.
  The first three contracts, for a total of 450 aircraft, were placed on March 10th, 1918, just over two weeks after the first flight of the prototype. Production D.H.10s were not delivered early enough to enable the type to be tested in action, however, for by October 31st, 1918, the R.A.F. had only eight D.H.10s on charge, and only two of those had reached the Independent Force. Had the war continued, the D.H. 10 could hardly have failed to prove to be an effective weapon with its fine performance, useful bomb load and good defensive armament.
  It was reported to be pleasant to fly, but some trouble was experienced with the fuel pumps, which were driven by small airscrews revolving freely in the airstream. These drove the pumps at air speeds above 70 m.p.h., but at lower air speeds the pumps were not so efficient, and one engine would be starved of fuel. The results of this could be unpleasant, especially at take-off, and caused some adverse criticism of the type before the difficulty was overcome.
  An improvement in performance was made by revising the position of the engines so that each was attached directly to the lower mainplane. This power installation was cleaner than the original, for it eliminated the struts which, in the D.H.10, supported each engine. With the revised engine arrangement the type was designated D.H.10A by the manufacturers, and was officially styled Amiens Mk. IIIa.
  Although neither the D.H.10 nor the D.H.10A took an active part in the war, two D.H.10s were allotted to an Experimental Armament Unit for experiments with the Coventry Ordnance Works 1 1/2-pounder quick-firing gun. One of these two machines had Rolls-Royce Eagle engines and may have been the second prototype. The other D.H.10 had Liberty engines, and was the only one of the two in which the gun was tested. The weapon was mounted in the nose cockpit, and in addition to the gunner an observer was carried in the rear seat. This D.H.10 crashed during the armament experiments, but it seems that the Eagle-powered machine was not used even then.
  The D.H.10 was one of the aeroplanes which took part in the early post-war air-mail flights, especially on the R.A.F.’s air-mail service for the British Army of Occupation; this service began on March 1st, 1919. The terminal points of the route were Hawkinge and Cologne, and transportation of the mails was regarded as a normal duty of No. 120 Squadron. This unit had some D.H.10s on its strength, and it was a D.H.10 which gained the distinction of being the first aeroplane to carry mail at night. The first experimental night-mail flight was made on the night of May 14th/15th, 1919, by a D.H.10 manned by Captain Barrett, Lieutenant Fitzmaurice and Lieutenant Oliver, who left Hawkinge at 10.15 p.m. on May 14th and reached Cologne at 1.30 a.m. the following morning.
  In addition to its good work on the early air-mail routes the D.H.10 was flown by the R.A.F. on the North-West Frontier of India during the early 1920s. Some of the machines used in India had an additional cockpit immediately behind the pilot and in line with the leading edge of the lower wing.
  A late development of the design was the D.H.10C, officially designated Amiens Mk. IIIc. This version had two 375 h.p. Rolls-Royce Eagle VIII engines mounted in D.H.10A style directly on the lower mainplane. It is probable that this engine change was made because of the cessation of deliveries of the Liberty engine in July, 1918, and it was intended to put the D.H.10C into production: one of the contractors for the type was to have been the Mann, Egerton company. The prototype D.H.10C, E.5557, was used during 1919 by Aircraft Transport and Travel, Ltd., the subsidiary of the Aircraft Manufacturing Co. It was then based at Hendon.
  The designation D.H.10B is usually attributed to the civil-registered D.H.10 G-EAJO, which was modified for the carriage of air-mail.
  A D.H.10 participated in a series of experiments which were conducted to investigate the controllability of twin-engined aircraft in the event of failure of one engine. At first, the single fin and rudder were replaced by twin fins and horn-balanced rudders mounted wholly above the tailplane. These new surfaces were more or less of typical D.H. outline, and were mounted at three different angles: parallel, toed-in at 7 1/2 degrees and toed-in at 15 degrees. Each fin was 9-5 sq ft in area; each rudder 19-5 sq ft.
  From this tail-unit was developed another with twin fins and rudders. This had vertical surfaces of angular outline which extended above and below the tailplane; cut-outs were made in the elevators to permit rudder movement. Total fin area on each side was 12-5 sq ft, and each rudder was 12-5 sq ft.
  A third experimental tail-unit consisted of a rectangular fin of low aspect-ratio, 19 sq ft in area, and a large horn-balanced rudder of 39 sq ft. This rudder was at first over-balanced, and the balance area was twice reduced before it became satisfactory.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: The Birmingham Carriage Co., Birmingham; The Daimler Co., Ltd., Coventry; National Aircraft Factory No. 2, Heaton Chapel, near Stockport; The Siddeley-Deasy Motor Car Co., Ltd., Park Side, Coventry; The Alliance Aeroplane Co., Ltd., Cambridge Road, Hammersmith, London, W.14; Mann, Egerton & Co., Ltd., Norwich.
Power: Amiens Mk. I: two 230 h.p. B.H.P., installed as pushers. Amiens Mk. II: two 360 h.p. Rolls-Royce Eagle VIII. Amiens Mk. III and IIIa: two 400 h.p. Liberty 12. Amiens Mk. IIIc: two 375 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: Mks. I and II, 62 ft 9 in.; Mks. Ill and IIIa, 65 ft 6 in. Length: Mks. I and II, 38 ft 10 1/8 in.; Mks. Ill and IIIa, 39 ft 7 7/16 in. Height: 14 ft 6 in. Chord: 7 ft. Gap: 7 ft. Dihedral: 4 30'. Incidence: 7. Sweep-back: Mk. II, 40; Mks. Ill and IIIa, 2 30'. Span of tail: 22 ft. Airscrew diameter (Liberty): 10 ft.

Areas:
Mk. II Mks. Ill and IIIa
Wings, upper 427-4 sq ft 429-2 sq ft
lower 407-4 sq ft 408-2 sq ft
total 834-8 sq ft 837-4 sq ft
Ailerons, each 30-2 sq ft 29-5 s9 ft
total 120-8 sq ft 118-0 sq ft
Tailplane 71-6 sq ft 75-5 sq ft
Elevators 46-0 sq ft 33-08 sq ft
Fin 10-0 sq ft 10-0 sq ft
Rudder 25-75 sq ft 25-75 sq ft

  Tankage: Petrol: two main tanks, 98 gallons each; gravity tank, 19 gallons; total, 215 gallons. Oil: two tanks, 7 gallons each; total, 14 gallons.
  Armament: Both nose and rear cockpits were fitted with a Scarff ring-mounting, and each bore either a single Lewis gun or a double-yoked pair. The main bomb load could be carried internally, but additional external racks were also fitted under the lower wings. About 900 lb of bombs could be carried. Experimentally, one D.H. 10 had a 1 1/2-pounder Coventry Ordnance Works gun in the front cockpit.
  Service Use: No. 120 Squadron, R.A.F.
  Production and Allocation: A total of 1,295 D.H. 10s were ordered, but all were not delivered. On October 31st, 1918, the R.A.F. had only eight on charge, of which only two were in France with the Independent Force. Earlier in 1918 one D.H. 10 had been delivered to a Home Defence station.
  Notes on Individual Machines: C.8659 was Amiens Mk. II; C.8660 was Amiens Mk. Ill prototype. E.5507: used in India, had extra cockpit behind pilot. E.5557: became D.H.10C. E.6042: D.H. 10 later fitted with twin fins and rudders. E.7851: used in India, extra cockpit. F.1869: D.H.10A. F.1874: D.H.10. F.8421: D.H.10A.


Serial Numbers:
Serial Nos. Contractor
C.8658-C.8660 Aircraft Manufacturing Co.
E.5437-E.5636 Aircraft Manufacturing Co.
E.6037-E.6136 Birmingham Carriage Co.
E.7837-E.7986 Siddeley-Deasy
E.9057-E.9206 Daimler, Ltd.
F.351-F.550 National Aircraft Factory No. 2
F.1867-F.1882 Aircraft Manufacturing Co.
F.7147-F.7346 Alliance Aeroplane Co.
F.8421-F.8495 Mann, Egerton & Co.
H.2746-H.2945 Aircraft Manufacturing Co.
  
  Costs:
   D.H.10 (Liberty) airframe without engines, instruments and guns £3,483 7s.
   Liberty engine (each) £1,215 0s.

de Havilland 9A

  THE story of the designing of the American Liberty engine was launched in a blaze of publicity on August 12th, 1917, when an official statement was issued by the American Secretary of War. This statement described how the first engine was completed only twenty-eight days after the drawings were commenced, unquestionably a fine engineering achievement, and went on to describe the sterling qualities of the new power unit in glowing terms. The description of the first Liberty as “the best aircraft engine produced in any country” was somewhat premature, however, for it had not flown at the date of the Secretary of War’s statement.
  The first Liberty was an eight-cylinder vee engine, designed by Major J. G. Vincent of the Packard company and Major J. G. Hall of the Hall-Scott company, who first met to discuss the design requirements on June 3rd, 1917. The first engine was assembled on July 3rd, 1917, underwent its first bench test on July 23rd, and was flown for the first time on August 20th.
  The construction of a twelve-cylinder version was also put in hand. This engine successfully completed a fifty-hour bench test on August 25th, 1917, and was originally rated at 314 h.p. The output was increased to 395 h.p. by October, in which month the engine was first flown in a D.H.4, and in December, 1917, serious development of the eight-cylinder model was abandoned in favour of the bigger engine.
  Production of the Liberty 12 had already begun, but the original programme was over-ambitious and was never realised: the monthly output which was envisaged was 4,800, which was to be reached by May, 1918. Total deliveries by the end of that month were to reach a figure of 9,420, but in fact only 1,100 Liberty engines had been produced by that date. Production was delayed by lack of jigs, tools and gauges, and the supposedly perfect engine was the subject of no fewer than 1,022 modifications between September, 1917, and February, 1918.
  Nevertheless, the production of 1,100 engines in twelve months from the commencement of design was a considerable achievement.
  The high power output of the engine made it an attractive proposition, and it appealed particularly to Britain as an alternative to the Rolls-Royce Eagle, production of which was falling short of demand. The Allied governments asked for large numbers of Liberties, and by the end of January, 1918, Britain had asked for a total of 3,000. Delivery was to begin that month, and was to be at the rate of 500 per month; but the first ten did not arrive until March, 1918. Deliveries ceased in July, by which time only 1,050 engines were delivered.
  In the expectation of plentiful supplies of Liberty engines, it was decided that the new engine should be used to power a day-bomber type based on the D.H.9 design. At that time, however, the Aircraft Manufacturing Co. were fully occupied with the design of the D.H.10 and were unable to devote any time or personnel to the designing of the new Liberty-powered machine. Responsibility for the modification of the basic D.H.9 design was therefore entrusted to the Westland Aircraft Works, who had been contractors for the manufacture of D.H.4s and D.H.9s.
  The re-designing produced an aeroplane which bore a superficial resemblance to the D.H.4, for the radiator was mounted immediately behind the airscrew. New wings of increased span and chord were fitted, and the fuselage box-girder structure was fully cross-braced by wires, whereas the fuselage of the D.H.9 had embodied a number of plywood cross partitions in place of wires. The plywood covering on the forward portion of the fuselage was retained, and there was a clear-view cut-out in the root of the starboard lower wing.
  The first D.H.9A - for such was the designation of the modified aircraft - was a converted D.H.9, B.7664, which appeared with a 375 h.p. Rolls-Royce Eagle VIII engine, presumably because no Liberty was immediately available. The installation of the Eagle was almost identical to that used for the Liberty, but could be distinguished by the longer exhaust pipes and four-bladed left-hand airscrew. Other D.H.9As had the Rolls-Royce Eagle engine, but the great majority had the Liberty. The first Liberty-powered D.H.9A was C.6122.
  Contracts for production of the D.H.9A were let in March, 1918, and by the end of June eighteen machines had been delivered. During that month Major-General H. M. Trenchard had written from France to say that it was imperative to make every effort to replace the D.H.9s with D.H.9As, but the first squadron to be equipped with the new machine did not arrive in France until August 31st, 1918.
  This unit was No. 110 Squadron, and all its D.H.9As were presented to the R.A.F. by His Serene Highness the Nizam of Hyderabad. Each aircraft bore an inscription to that effect, and the unit became known as the Hyderabad Squadron. On its arrival in France, No. 110 Squadron joined the Independent Force, and carried out its first bombing raid on September 14th, 1918: the objective was the enemy aerodrome at Boulay. The part played by the D.H.9A in the Independent Force’s programme of strategic bombing of industrial targets was not large: in fact, No. 110 Squadron made only five such sorties before the Armistice.
  The squadron’s last strategic attack was made on Frankfurt on October 21st, 1918, and can only be regarded as a fiasco. Thirteen D.H.9As set out from Bettoncourt: one returned with engine trouble, and the formation was broken up by dense clouds; seven failed to return. By that time, of course, the tempo of aerial fighting had quickened enormously, and during its two operational months No. 110 Squadron lost seventeen D.H.gAs by enemy action; a further twenty-eight were wrecked.
  The Liberty engine was not at first successful; indeed, in view of the melodramatic story of its creation, it was looked upon with a certain amount of derision. Much of the trouble was caused by the engine’s coil ignition, to which R.A.F. pilots did not take kindly; but once the engine was properly understood it ran extremely well. It certainly gave the D.H.9A a much better performance than the D.H.9, and remained the standard power unit of the type throughout its long post-war service.
  No. 205 Squadron began to replace their D.H.4s with D.H.9As at the end of August, 1918, and reequipment was complete by the end of the following month. This unit did much good work on the Fourth Army front during the final advance of the Allies. The good performance of the D.H.9A enabled the squadron to fly unescorted, whereas the D.H.9 squadrons had to be escorted to the limits of the range of the fighters.
  The only other units to receive the D.H.9A before the Armistice were Squadrons Nos. 18 and 99; in both cases re-equipment was proceeding in November, 1918. Coastal units began to receive D.H.9As for oversea patrol during the late summer of 1918, but they were not used for that purpose because the original valve gear of the Liberty was not considered safe for over-water flying. The type arrived too late to see action in any other theatre of war, but after the Armistice some went to Russia with Squadrons Nos. 47 and 221, where they shared the rigours of a sub-Arctic winter with D.H.9s.
  The D.H.9A was built, doubtless without licence, in post-Revolutionary Russia. Its Russian designation was R-1, the R signifying “Razv’edchik”, or reconnaissance aircraft. The first Russian-built machines are believed to have had Liberty engines, but later examples were powered by the M-5 engine, which was a copy of the Liberty.
  The fact that the D.H.9A was powered by the Liberty engine naturally commended it strongly to the United States Air Service, and arrangements were made for its manufacture in America. Probably for reasons of prestige, the American version was designated USD-9A. The Dayton-Wright concern built four in October, 1918, and these were followed next month by five constructed by the Engineering Division of the Bureau of Aircraft Production. A contract for 4,000 was given to the Curtiss Aeroplane Co., but was cancelled at the Armistice. Production USD-9As were to have a rudder of slightly more rounded outline than that of the D.H.9A, and the pilot’s Browning gun was mounted on the starboard side. In February, 1919, the Engineering Division fitted wings of increased area to one of their USD-9As and installed a 420 h.p. Liberty 12A engine: this machine was re-designated USD-9B.
  After the war, the D.H.9A remained in service with the R.A.F. for many years at home and overseas. In company with the equally long-lived Bristol Fighter, it undertook the policing of Iraq and the control of refractory tribesmen on the North-West Frontier of India. In its post-war days, the D.H.9A became a general purpose type, and carried a remarkable variety of equipment which included a spare wheel and, when occasion demanded it, water contained in animal skins attached to the gun-ring outside the fuselage. The type ended its career with the Auxiliary squadrons.
  Several D.H.9As were fitted with the Napier Lion engine in the post-war years: the first installation was made in 1919. Oleo undercarriages were also fitted, and J.6957 combined the Lion engine with an oleo undercarriage somewhat reminiscent of that used on Fairey landplanes.
  A further development was the D.H. Stag, which first flew on June 15th, 1926. This was a D.H.9A fitted with a 465 h.p. Bristol Jupiter radial engine; stagger was reduced and a simplified oleo undercarriage was installed.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Other Contractors: F. W. Berwick & Co., Ltd., Park Royal, London, N.W. 10; Mann, Egerton & Co., Ltd., Aircraft Works, Norwich; The Vulcan Motor and Engineering Co. (1906), Ltd., Crossens, Southport; Westland Aircraft Works, Yeovil, Somerset.
  Power: 375 h.p. Rolls-Royce Eagle VIII; 400 h.p. Liberty 12; 450 h.p. Napier Lion; 400 h.p. M-5 (Russian copy of Liberty for Russian-built D.H.9As).
  Dimensions: Span: 45 ft 11 3/8 in. Length: 30 ft 3 in. Height: 11 ft 4 in. Chord: 5 ft 9 in. Gap: 5 ft 6 in. Stagger: 1 ft 4 in. Dihedral: 3°. Incidence: 3°. Span of tail: 13 ft 10 in. Wheel track: 6 ft. Airscrew diameter: 10 ft.
  Areas: Wings: upper 249-03 sq ft, lower 237-7 sq ft, total 486-73 sq ft. Ailerons: each 18-59 sq ft, total 74-36 sq ft.
Tailplane: 38 sq ft. Elevators: 24 sq ft. Fin: 5-4 sq ft. Rudder: 13-7 sq ft.

Serial Numbers:
Serial Nos. Contractor
B.7664 (converted D.H.9, Eagle engine) Westland Aircraft
C.6122 (Liberty) Westland Aircraft
C.6350 (Eagle) Aircraft Manufacturing Co.
E.701-E.1000
E.8407-E.8806 Aircraft Manufacturing Co.
E.9657-E.9756 Mann, Egerton & Co.
E.9857-E.9956 Vulcan Motor & Engineering Co.
F.951-F.1100 Westland Aircraft
F.1603-F.1652 Westland Aircraft

  Other Known Serial Numbers: F.2816-F.2869, F.3842, F.9922; H.1-H.150 (at least); between and about H.3430 and H.3650 (H.3486 was built by Westland); H.4243: Westland-built. H.4275. Between and about J.554 and J.568; J.6957-J.6959; J.7008, J.7009, J.7024, J.7030, J.7034, J.7035, J.7038, J.7039, J.7041. J.7047. J.7048, J.7058, J. 7059, J.7062-J.7083, J.7085, J.7086, J.7089, J.7094, J.7107, J.7109, J.7116, J.7117, J.7122, J.7124, J.7302, J.7309, J.7316, J.7329, J.7331-J.7333, J.7337, J.7340, J.7342, J.7356, J.7605, J.7607, J.7614, J.7615, J.7787-J.7798, J.7809, J.7814, J.7818, J.7831, J.7832, J.7835, J.7842, J.7850, J.7854, J.7877-J.7883, J.7888, J.7890, J.8098-J.8223; J.8462, J.8470, J.8472, J.8473, J.8478, J.8489, J.8492.

Weights (lb) and Performance:
Engine Rolls-Royce Eagle VIII Rolls-Royce Eagle VIII Rolls-Royce Eagle VIII Liberty Liberty Lion
Bomb load Nil Two 230-lb Two 230-lb, 14 20-lb Nil Two 230-lb -
No. of Trial Report M.182 M.182 M.182 M.213 M.213 -
Date of Trial Report March, 1918 March, 1918 March, 1918 July, 1918 July, 1918 -
Type of airscrew used on trial D.G.2160 D.G.2160 D.G.2160 X.3012M X.3012M -
Weight empty 2,705 2,705 2,705 2,770 2,800 2,557
Military load 185 608 1,200 185 580 -
Crew 360 360 360 360 360 -
Fuel and oil 550 550 550 905 905 -
Weight loaded 3,800 4,223 4,815 4,220 4,645 4,660
Maximum speed (m.p.h.) at
ground level - - - - 123 -
10,000 ft 125-5 118 1105 120 114-5 134
15,000 ft 116 104-5 - 114 106 125-5
16,500 ft - - - - 102 -
m. s. m. s. m. s. m. s. m. s. m. s.
Climb to
2,000 ft - - - - - - 1 50 2 20 - -
5,000 ft - - - - - - 5 00 6 25 - -
6,500 ft 7 00 8 40 11 00 6 50 8 55 - -
10,000 ft 12 10 15 35 20 35 11 50 15 45 10 30
15,000 ft 22 55 33 40 - - 22 50 33 00 - -
16,500 ft - - - - - - - - 43 50 - -
Ceiling (feet): Service 20,000 16,000 14,000 19,000 16,750 21,300
Absolute 22,000 - - 21,000 18,000 -
Endurance (hours) 4 1/2 - 3 1/2 5 3/4 5 1/4 -

  Tankage: Petrol: 107 gallons, carried in two 50-gallon tanks mounted between the engine and the pilot’s cockpit, and in a 7-gallon gravity tank in the centre-section. Oil: 15 gallons in tank in front of petrol tank. Water: 10 1/2 gallons.
  Armament: One fixed forward-firing Vickers machine-gun mounted on the port upper longeron just in front of the pilot’s cockpit, synchronised by Constantinesco C.C. Gear type B. The observer had either a single Lewis gun or a double-yoked pair on a Scarff ring-mounting on the rear cockpit. The normal bomb load consisted of two 230-lb bombs, but up to 660 lb of bombs could be carried: bombs were carried on racks under the fuselage and lower wings.
  Service Use: Western Front: R.A.F. Squadrons Nos. 18, 99, no and 205. Russia: R.A.F. Squadrons Nos. 47 and 221. Coastal Units: R.A.F. Squadrons Nos. 212 and 273. Training: used at various training aerodromes, including Cranwell, Fowlmere, Waddington.
  Production and Allocation: By the end of December, 1918, a total of 885 D.H.9As had been built. By October 31st, 1918, 272 had been delivered to the R.A.F.: seventy went to the Expeditionary Force, eighty-nine to the Independent Force, and 113 to training units. There were 405 D.H.9As on charge of the R.A.F. on October 31st, of which sixty-six were with the Expeditionary Force, eighty-three with the Independent Force, twelve at coastal aerodromes, fifty at training units, 105 with contractors, twenty-five with squadrons mobilising, two at Aeroplane Repair Depots, twenty-four in store, and thirty-eight were at sundry stations.
  Costs:
   Airframe without engine, instruments and guns £1,599 12s.
   Engines:
   Liberty 12 £1,215 0s.
   Eagle VIII £1,622 10s.

de Havilland 11, the Oxford

  IN 1918 the Air Ministry asked the Aircraft Manufacturing Co. to build a long-range day bomber, presumably with a view to providing an ultimate replacement for the D.H.10. The type number D.H.11 was allotted to the new design, which was completely different from any of its predecessors and displayed great originality of thought. Construction was hardly begun when the Armistice was signed, and the uncertainties of the ensuing period, coupled with the lack of any urgency, delayed the machine’s completion until early 1920. The name Oxford was officially bestowed on the D.H.11, but did not survive and is little known.
  The D.H.11 was a three-bay biplane powered by two A.B.C. Dragonfly radial engines mounted on the lower wings. The fuselage was very deep and completely filled the gap between the wings. This arrangement gave the rear gunner a superb field of fire in all upwards directions, for he was wholly above the wings. The front and rear gunners’ cockpits were connected by a catwalk which led past the pilot’s seat and under the fuel tanks: these were slung from the top of the fuselage. The machine stood high on the ground, and access to the fuselage was gained by a trapdoor situated between the spars of the lower wing.
  A remarkable structural feature of the D.H.11 was the use of a simple vee undercarriage generally similar to the type found on most contemporary single-engined aircraft. This must have led to a number of complications concerning the engines and lower centre-section.
  The wings were conventional in appearance and construction, but the upper mainplanes had a greater dihedral angle than the lower. Balanced ailerons were fitted. The tail-unit was of typical de Havilland outline, and the tailplane was braced to the lower longerons by faired steel tubes.
  In common with so many of its twin-engined contemporaries which were intended to have the Dragonfly engines, the D.H.11 design had to be modified to accommodate the Siddeley Puma engine in order to enable flying trials to proceed in the event of non-availability of the Dragonflies. The Puma-powered version was designated Airco Oxford Mk. II, but it is doubtful whether any D.H.11 was ever built with such engines.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Power: Oxford Mk. I: two 320 h.p. A.B.C. Dragonfly. Oxford Mk. II: two 290 h.p. Siddeley Puma.
  Dimensions: Span: 60 ft 2 in. Length: 45 ft 2 3/4 in. Height: 13 ft 6 in. Gap: maximum 7 ft 2 in., minimum
5 ft 10 in. Stagger: nil. Dihedral: upper 4°, lower 2°. Span of tail: 15 ft 2 in.
  Areas: Wings: 719 sq ft. Ailerons: each 25-5 sq ft, total 102 sq ft. Tailplane: 55 sq ft. Elevators: 30-5 sq ft. Fin: 7-4 sq ft. Rudder: 20 sq ft.
  Weights: Empty: 3,795 lb. Military load: 1,240 lb. Crew: 540 lb. Fuel and oil: 1,425 lb. Weight loaded: 7,000 lb.
  Performance (estimated): Maximum speed at 6,500ft: 117 m.p.h.; at 10,000 ft: 115 m.p.h. Climb to 10,000 ft:
13 min 30 sec. Endurance: 3 1/4 hours.
  Tankage: Petrol: 170 gallons.
  Armament: Two free Lewis machine-guns; one on a Scarff ring-mounting on the nose cockpit, another on a similar mounting on the rear cockpit. The bomb load was probably about 1,000 lb.
  Serial Number: H.5681.

de Havilland 14, the Okapi

  THIS massive single-engined biplane was designed as a replacement for the D.H.4, D.H.9 and D.H.9A in the day-bomber squadrons. Design work began before the Armistice, but construction was not completed until 1919. In late 1918, the type was officially (and somewhat incongruously) named Airco Okapi.
  In appearance the D.H.14 was entirely conventional. It was a straightforward two-seat two-bay biplane with a plain vee undercarriage and the usual de Havilland tail-unit, but it was one of the first aeroplanes to have the then-new Rolls-Royce Condor twelve-cylinder vee engine which delivered no less than 600 h.p. The engine was installed behind a large flat rectangular radiator, and drove a four- bladed airscrew. Internal stowage for the bombs was provided in the capacious fuselage.
  The Rolls-Royce company had begun design work on the engine which was named Condor late in
It was generally similar to the Eagle but had four valves per cylinder instead of the Eagle’s two; and, with a displacement of 2,138 cu in., was a much larger engine. The Condor was originally intended to be the power unit for the Handley Page V/1500. The first Condors were not available until early 1919; they developed 600 h.p., but were type-tested at only 525 h.p.
  The Armistice prevented the development and production of the D.H.14, but in 1920 a specially modified machine appeared under the type number D.H.14A. This aircraft had a Napier Lion engine of 450 h.p., and an additional pair of wheels were ultimately added to the undercarriage in front of the normal wheels in order to lessen the risk of nosing-over on bad ground. The D.H.14A was intended for use as a high-speed mail-carrier, and in 1920 it began an attempt to fly to South Africa. Unfortunately, it was wrecked in a forced landing in Italy.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Power: 600 h.p. Rolls-Royce Condor.
  Dimensions: Span: 50 ft 5 in. Height: 14 ft. Chord: 6 ft 6 in. Gap: 6 ft 10 in. Dihedral: 3. Span of tail: 15 ft 3 in.
  Areas: Wings: 617 sq ft. Ailerons: each 2359 ft, total 92 sq ft. Tailplane: 58 sq ft. Elevators: 31-5 sq ft. Fin:
5-9 sq ft. Rudder: 15-4 sq ft.
  Weights: Loaded: 7,074 lb.
  Armament: One fixed forward-firing Vickers machine-gun, synchronised by Constantinesco gear, for the pilot; one free Lewis machine-gun on Scarff ring-mounting on rear cockpit for the observer. Four bombs could be carried internally in cells between the spars of the lower wings; two more bombs were carried internally under the pilot’s seat.
  Serial Numbers: J.1938-J.1939.

de Havilland 15, the Gazelle

  THE D.H.15 was essentially a D.H.9A airframe which had been modified to accommodate the 500 h.p. B.H.P. Atlantic twelve-cylinder vee engine. As a modification of a tried and tested type, it may have been designed as an insurance against the failure of the D.H.14.
  The Atlantic engine was first made in 1918 by the Galloway Engineering Co., and was produced by combining two ordinary B.H.P. cylinder blocks on a common crankcase. These were of cast iron and, as on the original B.H.P. engine, there was no reduction gear.
  The new engine was selected for mass production, and twenty-five had been delivered by October 31st, 1918. However, just as the original B.H.P. or Galloway Adriatic had given way to the Siddeley Puma, so was the Galloway Atlantic re-designed to become, in effect, a double Puma, with aluminium cylinder blocks. The re-designed engine was named Siddeley Pacific, and was ordered on a large scale.
  The D.H.15 served as a flying test-bed for the Galloway Atlantic engine, and made its first flight in 1918. In appearance it differed little from the D.H.9A, for the shape of radiator used with the Atlantic differed only slightly from that of the Liberty. The chief distinguishing feature of the D.H.15 lay in its long horizontal exhaust pipes; and the forward centre-section struts were more nearly vertical in side elevation than were those of the D.H.9A.
  Despite its experimental nature, the D.H.15 was given an official name: under the scheme of nomenclature defined in Technical Department Instruction No. 538 it was designated Airco Gazelle.


SPECIFICATION
  Manufacturers: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.
  Power: 500 h.p. B.H.P. (Galloway) Atlantic.
  Dimensions: Span: 45 ft 11 f in. Length: 29 ft 11 in. Chord: 5 ft 9 in. Span of tail: 13 ft 10 in.
  Areas: Wings: upper 249-03 sq ft, lower 237-7 sq ft. total 486-73 sq ft. Ailerons: each 18-59 sq ft. total 74-36 sq ft. Tailplane: 38 sq ft. Elevators: 24 sq ft. Fin: 5-4 sq ft. Rudder: 13-7 sq ft.
  Weights: Empty: 2,312 lb. Loaded: 4,773 lb.
  Performance: Maximum speed at ground level: 139 m.p.h.; at 6,500 ft: 136-5 m.p.h.; at 10,000 ft: 133 m.p.h. Climb (at 4,230 lb loaded weight) to 6,500 ft: 4 min 55 sec; to 10,000 ft: 8 min 12 sec. Ceiling: 20,000 ft.
  Tankage: Petrol: 108 gallons. Oil: 14 gallons.
  Armament: One fixed forward-firing Vickers machine-gun on port upper longeron just in front of pilot’s cockpit, synchronised by Constantinesco C.C. Gear; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Serial Numbers: J.1936-J.1937.

Dyott Bomber

  G.M. DYOTT was one of the pioneers of aviation in Britain: his Royal Aero Club pilot’s certificate was No. 114 and was granted on August 17th, 1911. Some eighteen months later he designed a neat little monoplane, powered by a 50 h.p. Gnome engine, on which he did a good deal of flying at home and in America.
  Just before the war he designed a large twin-engined biplane which was intended to be used for exploration work in South Africa. It appears that the Admiralty saw possibilities in the type as a bomber, and construction of a modified version of the design was undertaken in 1915 by Hewlett & Blondeau, Ltd., who had built the little Dyott monoplane two years earlier.
  The machine was never adopted for Service use, although it was flown at Chingford in 1916. It seems probable that the Dyott would be underpowered with no more than 340 h.p. provided by two Beardmore engines, especially as flown with all its defensive armament mounted. The retention of the jackets on the Lewis guns seems to indicate a low speed.
  The aircraft was a large biplane with wings of equal span. Upper and lower centre-sections spanned the distance between the engines; the outboard sections of the wings had four bays of bracing. The fuselage accommodated three crew members, and had a nosewheel directly under the front cockpit. Construction appeared to be conventional throughout, and the Dyott was quite a handsome aeroplane.
  The Dyott underwent several detail modifications during its existence. When it first appeared, its engines were uncowled and the radiators were installed as multiple elements above the engines. The long front cockpit was encircled by an elevated rail which connected six separate spigot-mountings for Lewis guns; abaft this cockpit the top-decking was flat and sloped upwards to the pilot’s cockpit.
  At a later stage frontal radiators were fitted, and the engines were cowled quite cleanly; exhaust manifolds were also fitted. The top-decking on the fuselage nose was deepened considerably and apparently came up to the level of the rail surrounding the nose cockpit. The top-decking continued straight back to the pilot’s cockpit.
  In this form the Dyott appeared with the heavy defensive armament detailed in the armament notes below. The nose armament of four Lewis guns was obviously unwieldy and could not have been used effectively in combat. The Dyott was sent to France for Service trials with the R.N.A.S. but did not prove to be sufficiently successful to merit adoption as a standard type.


SPECIFICATION
  Manufacturers: Hewlett & Blondeau, Ltd., Oak Road, Leagrave, Luton.
  Power: Two 120 h.p. Beardmore.
  Armament: Five free Lewis machine-guns. Four were in the nose: two of these were on spigot-mountings above the fuselage and could probably be moved from one mounting to another; each of the other two fired through a porthole on either side of the nose. The fifth gun was on a mounting in the cockpit aft of the wings.
  Serial Numbers: 3687-3688.

Fairey F.2

  THE Fairey Aviation Co., Ltd., was founded by C. R. (later Sir Richard) Fairey in 1915. The firm’s first products were a batch of a dozen Short seaplanes Type 827 with the 150 h.p. Sunbeam engine: these were tested at Hamble by Sidney Pickles late in 1915.
  In the following year there appeared the first Fairey-designed aeroplane. Described by its makers as a long-range fighter, it was a large but quite handsome twin-engined three-seat biplane which could obviously have carried a load of bombs if required to do so.
  The new Fairey biplane was built for the Admiralty, and it has been reported that the original order was for four aircraft numbered 3702-3705; the first two were to have two 200 h.p. Brotherhood engines installed as tractors; the second two were to have two 190 h.p. Rolls-Royce engines driving pusher airscrews. In the event, however, only one machine was completed. It was powered by two of the Rolls-Royce engines which were fitted as tractor units. The completed aircraft had the official serial number 3704 and the Fairey works number F.2.
  The basic structure of the Fairey F.2 was the usual wire-braced wooden affair with fabric covering. The undercarriage was substantial, and had four main landing wheels: the forward pair were intended to prevent the machine from nosing over on rough ground. The upper wings had long extensions braced from king-posts situated above the outer interplane struts, and the engines were mounted fairly well up in the gap. The mainplanes could be folded back to conserve hangar space; the fold was made immediately outboard of the engines, which were enclosed in simple nacelles and drove opposite-handed airscrews to eliminate torque reaction.
  Construction was complete by the autumn of 1916, and the F.2 proved that it had quite a good performance for an aeroplane of its size and power. The type was not adopted for Service use, however.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex.
  Power: Two 190 h.p. Rolls-Royce (Falcon).
  Dimensions: Span: 77 ft. Length: 40 ft 6 1/2 in. Height: 13 ft 5 5/8 in. Chord: 5 ft 6 in. Gap: 6 ft. Stagger: nil. Span of tail: 17 ft 6 in.
  Areas: Wings: 718-4 sq ft. Ailerons: each 47-8 sq ft, total 95-6 sq ft. Tailplane: 64-9 sq ft. Elevators: 39 sq ft. Fins: each 10-9 sq ft. Rudders: each 10 sq ft.
  Weights: Loaded: 4,880 lb.
  Performance: Maximum speed at ground level: 92-5 m.p.h. Climb to 5,000 ft: 6 min. Endurance: 3 1/2 hours.
  Armament: One free Lewis machine-gun on Scarff ring-mounting on nose cockpit; a second Lewis gun was carried on a similar mounting on the rear cockpit. Bombs could be carried on external racks.
  Serial Numbers: It is believed that the serial numbers 3702-3705 were allotted for Fairey twin-engined biplanes of F.2 basic design; only 3704 was completed.

Fairey Hamble Baby

  THE Hamble Baby was a modification of the Sopwith Baby single-seat seaplane, and its genesis was brought about by the same circumstances which produced the so-called Blackburn Baby.
  The Fairey approach to the problem of improving the performance with load of the Baby design was more radical than that of the Blackburn Company: it produced an aircraft which was not only virtually a new type but one which was of considerable significance. The Hamble Baby’s most important design feature lay in the incorporation of the Fairey Patent Camber Gear, for this was the first intelligent use ever made of a form of trailing-edge flap to increase the lift of an aeroplane’s wings.
  To assist in development of the design in the early stages, a Sopwith-built Baby, No. 8134, was delivered to the Fairey company’s works at Clayton Road, Hayes. The wings were completely re-designed, and production machines had rounded wing-tips in place of the blunt plan-form of the original Sopwith machines. The Fairey Patent Camber Gear consisted of hinged flaps, one of which was attached to each mainplane and ran along the full length of the trailing edge. These flaps acted as the ailerons in normal flight, but by means of a differential control system they could be wound down to act as a lift-increasing device. The thin aerofoil sections which were in use at the time could not give a very high lift coefficient at any time, but the Fairey flaps did produce a worthwhile increase in lift and enabled the Hamble Baby to lift its two 65-lb bombs with comparative ease. The very size of the flaps made lateral control rather heavy, but it was effective right down to the stall. The Hamble Baby had wheel control for the ailerons.
  The fuselage was virtually identical to that of the original Sopwith Baby, but the tail-unit was redesigned: the fin and rudder were of the near-square outline that had first appeared on the Campania. Fairey-designed floats were used, and a new tail-float of large volumetric capacity was fitted.
  The tests of the Hamble Baby were carried out by Squadron Commander Maurice Wright, and production was undertaken by the Fairey company and by Parnall & Sons of Bristol; oddly enough, the majority of the Hamble Babies were built by the latter concern. The Parnall-built machines were distinguished by their retention of the original Sopwith-style main floats, fin and rudder. The first fifty machines, N.1190-N.1219 and N.1320-N.1339, were built with the 110 h.p. Clerget rotary motor, but all subsequent Hamble Babies had the 130 h.p. Clerget.
  Although the Parnall-built machines were so similar externally to those built by the Fairey company, there were differences in detail construction; stores indents for the type had to quote the name of the constructor and the aircraft serial number. This was an unusual requirement, even during the 1914-18 war.
  The last seventy-four machines built by Parnall were fitted with a land undercarriage, and were known as Hamble Baby Converts. On these machines, horizontal skids replaced the floats; the main N- struts of the undercarriage remained unchanged, and the prodigiously long axle was bound to the skids by rubber cord. Thus did the wheel of design turn full circle, for the original Sopwith Baby was merely a float-plane version of the Sopwith Tabloid landplane.
  In service, the Hamble Babies carried out the same unspectacular but useful duties as their cousins built by Sopwith and Blackburn. From coastal stations in the United Kingdom, in the Mediterranean, and in the Aegean they carried out anti-submarine patrols. The seaplane carrier Empress had two Hamble Babies and four Sopwith Babies late in 1917, and its machines made some bombing attacks on Turkish installations in Palestine. On November 2nd, 1917, three of the Empress’ seaplanes attacked the railway bridge at Jaljulye with six 65-lb bombs, and later scored four hits on an oil factory near Haifa.

SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex, and at Hamble Point.
  Other Contractors: Parnall & Sons, Mivart Street, Eastville, Bristol.
  Power: 110 h.p. Clerget; 130 h.p. Clerget.
  Dimensions: Span: 27 ft 9 1/4 in. Length: 23 ft 4 in. Height: 9 ft 6 in. Chord: 4 ft 9 in. Gap: 4 ft 6 in. Span of tail: 10 ft 9 in.
  Areas: Wings: 246 sq ft. Ailerons: each 14-1 sq ft, total 56-4 sq ft. Tailplane: 2459 ft. Elevators: 17 sq ft. Fin: 4-3 sq ft. Rudder: 6-7 sq ft.
  Weights {with 110 h.p. Clerget): Empty: 1,386 lb. Military load: 185 lb. Pilot: 180 lb. Fuel and oil: 195 lb. Weight loaded: 1,946 lb.
  Performance: Date of Trial Report: May, 1917. Maximum speed at 2,000 ft: 90 m.p.h.; at 6,500 ft: 90 m.p.h. Climb to 2,000 ft: 5 min 30 sec; to 6,500 ft: 25 min. Service ceiling: 7,600 ft. Endurance: 2 hours.
  Armament: One fixed forward-firing Lewis machine-gun mounted on top of fuselage, and synchronised to fire forward through the revolving airscrew. Two 65-lb bombs carried side-by-side on racks under the fuselage.
  Service Use: R.N.A.S. Stations at Fishguard, Calshot, Cattewater. Mediterranean: seaplane station at Santa Maria di Leuca; seaplane carrier Empress. Aegean: seaplane stations at Suda Bay (Crete), Syra, Talikna (Lemnos), and Skyros. Egypt: seaplane stations at Port Said and Alexandria. Training: Hamble Baby Converts used at various R.N.A.S. aerodromes, e.g. Cranwell.
  Production and Allocation: One hundred and eighty Hamble Baby aircraft were built, fifty by the Fairey company and the remainder by Parnall and Sons. Of these, seventy-four were landplane Converts. By October 31st, 1918, only eighteen Hamble Babies remained on charge with the R.A.F.: nine were at home stations and nine in the Mediterranean.

Serial Numbers:
Serial Nos. Engine Contractor
N.1190-N.1219 110 h.p. Clerget Parnall
N.1320-N.1339 110 h.p. Clerget Fairey
N.1450-N.1479 130 h.p. Clerget Fairey
N.1960-N.2059 130 h.p. Clerget Parnall
(N.1986-N.2059 were Hamble Baby Converts)

Costs:
   Airframe without engine, instruments and gun £1,175 0s.
   130 h.p. Clerget engine £907 10s.

Fairey F.127

  IN 1917 the Fairey company built two experimental seaplanes which marked the beginning of the long and successful line of Fairey aircraft in the Series III, which was to endure almost up to the outbreak of the Second World War: the last descendants were the Fairey IIIF Mark V, or Gordon, and IIIF Mark VI, or Seal.
  The first of the two experimental seaplanes bore the Fairey works number F.127 and the Admiralty serial number N.9; both of these numbers came to be used as designations for the machine. It was powered by a 190 h.p. Rolls-Royce Falcon engine, and looked rather like a scaled-down Campania with single-bay wings. Historically speaking, it was the link between the Campania and the Series III machines.
  The Fairey F.127 was a remarkably neat two-seat seaplane which was intended to be used from seaplane carriers. It was much more compact than most contemporary seaplanes, and its wings could be folded back for stowage on board ship. Full use was made of the Fairey Patent Camber Gear: trailing edge flaps were fitted to the entire length of the lower wing, and to the upper wings between the ailerons and the centre-section. There were two radiator elements, one mounted on each side of the engine; and the exhaust stacks were led upwards through the centre-section as on the F.16 Campania.
  The F.127 was tested at Hamble and the Isle of Grain, but the type did not go into production. The machine survived long enough to take part in early British experiments with aircraft catapults.
  The Air Department of the Admiralty had considered the use of catapulting apparatus before the outbreak of war, but had shelved the idea. America had developed aircraft catapults to a useful degree by 1916, in which year three cruisers of the U.S. Navy had catapults. By mid-1916, the Admiralty recognised the value of aircraft carried in warships, and interest in aircraft catapults revived. Tenders were invited for the construction of a British catapult; and the specification required the apparatus to be capable of launching a 2 1/2-ton aeroplane at 60 m.p.h. in a distance of 60 feet with an acceleration not exceeding 2-5G.
  Two different catapults were ordered. The first to be completed was designed by R. F. Carey, and was tested at Hendon aerodrome with an Avro 504H and a Sopwith Pup. The second was designed and built by Messrs Armstrong, and was installed in a steam hopper, appropriately named Slinger, which had been specially commissioned for the experiments. First tests of the Armstrong catapult were made in September, 1917, in the Tyne.
  Later, the Slinger was sent to the Isle of Grain Experimental Aircraft Depot, where further experiments were conducted under the direction of Lieutenant-Colonel H. R. Busteed from June, 1918, onwards. The aeroplane used in these experiments was the Fairey F.127, anc’ successful launches were made with the Slinger at rest and under way. The F.127 was specially strengthened for catapulting, and additional struts were fitted to the forward horizontal tie-rod between the floats.
  The launching rail of the Armstrong catapult was about 60 feet long and was mounted centrally on top of a steel box girder. The launching trolley was pulled along the central rail by wire ropes, and was steadied by two additional rails. The prime mover was a cylinder of compressed air, and with very high pressure the catapult could achieve a speed of 60 m.p.h. In the trials with the Fairey F.127 the maximum speed employed was about 40 m.p.h., which speaks volumes for the controllability of the aircraft and the efficiency of the Fairey Patent Camber Gear. Stalling speed of the seaplane was 38 m.p.h., and the catapult launchings were made with the flaps down a few degrees. From the pilot’s point of view the use of the lower launching speed was advantageous, because no headrest was fitted to the F.127.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex.
  Power: 190 h.p. Rolls-Royce Falcon I.
  Dimensions: Span: upper 50 ft. Length: 35 ft 6 in. Height: 13 ft. Chord: 5 ft 6 in. Gap: 5 ft 7 in. Stagger: nil. Span of tail: 13 ft.
  Areas: Wings: 420 sq ft. Ailerons: each 18 sq ft, total 36 sq ft. Tailplane: 34-2 sq ft. Elevators: 34-2 sq ft. Fin: 8-9 sq ft. Rudder: 9-8 sq ft.
  Weights and Performance: Number of Trial Report: 8A. Date of Trial Report: July 5th, 1917. Weight empty: 2,699 lb. Military load: 216 lb. Crew: 360 lb. Fuel and oil: 537 lb. Weight loaded: 3,812 lb. Maximum speed at sea level: 90 m.p.h.; at 10,000 ft: 86 m.p.h. Climb to 2,000 ft: 4 min 10 sec; to 5,000 ft: 9 min 20 sec; to 6,500 ft: 18 min 30 sec; to 10,000 ft: 38 min. Service ceiling: 8,600 ft. Endurance: 5 1/4 hours.
  Tankage: Petrol: 70 gallons.
  Armament: One free Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Service Use: Used experimentally at the Marine Experimental Aircraft Depot, Isle of Grain, and on experimental catapult ship Slinger.
  Serial Number: N.9.

Fairey Campania

  THE second aircraft designed and built by the Fairey Aviation Co. was a two-seat patrol seaplane which was designed specifically for use from a carrier vessel. It was designed in 1916 with special regard to the hatchway dimensions and stowage capacity of H.M. Seaplane Carrier Campania.
  The Campania herself was an ex-Cunard passenger liner of 20,000 tons which had been built in 1893 and had a speed of about 22 knots. She was purchased by the Admiralty in October, 1914, at the suggestion of Captain Murray Sueter, for she was one of the few available ships with the speed and space required for a seaplane carrier. She was reconstructed by Cammell, Laird to accommodate ten seaplanes, and was fitted with a 120-foot flying deck above the forecastle. Campania was commissioned on April 17th, 1915, under Captain O. Swann.
  The deck was used for flying-off only, not for landing-on. For take-off, the seaplanes were placed on a form of trolley, the wheels being discarded as soon as the aircraft became airborne. At first these wheels were allowed to fall into the sea, but experiments produced a trolley which could be stopped at the end of the flight deck and retrieved for further use. The trolley was not at first used on Campania, but unsuccessful attempts to fly seaplanes off the sea after being hoisted out cost so much in broken floats and sunken aircraft that the use of the device became essential.
  The first take-off from Campania's deck, using the trolley, was made on August 6th, 1915, by Flight-Lieutenant W. L. Welsh, flying a Sopwith Schneider. The take-off run was 113 feet, and the attempt was made with Campania steaming at 17 knots against the wind. It was obvious that the deck was too short to enable any aeroplane larger than a Schneider to be flown off, so Campania returned to Cammell, Laird’s Liverpool yard to have her flying deck lengthened. Another modification was made to enable an inflated kite-balloon to be carried aft, and the Campania rejoined the Grand Fleet at Scapa Flow on April 12th, 1916, with her flying deck extended to some 200 feet.
  The Fairey seaplane was named Campania after its intended mother-ship. The first machine had the Fairey works number F.16, and was powered by the 250 h.p. Rolls-Royce Mk. IV (later named Eagle IV) engine. The exhaust manifolds terminated in upright stacks which were raked slightly backwards and passed through the centre-section just in front of the main spar. The radiator was disposed in two elements mounted externally, one on either side of the engine. The rather slender fuselage was of conventional construction; and the undercarriage consisted of two pontoon-type floats and a substantial tail-float, to which was attached a water-rudder. The main floats were attached to the undercarriage struts by elastic shock absorbers with limited range of movement. Small wing-tip floats were attached directly to the underside of the lower wings.
  The wings had two-bay bracing and there were extensions on the upper wings. The king-post structures from which the extensions were braced were of triangular form on the first Campania. Ailerons were fitted to the upper wings only. Since the Campania was intended for operation from carrier vessels the wings could be folded.
  The first Campania made a flight from the Isle of Grain to Scapa Flow: this was a considerable achievement at that time, and spoke well for the machine’s capabilities as a patrol seaplane. The pilot on this occasion was Squadron Commander Maurice Wright, who later became a director of the Fairey company.
  The second Campania, works number F.17, embodied several modifications. The more powerful 275 h.p. Rolls-Royce Mk. I (Eagle V) engine was installed. In this version the engine was mounted rather farther forward, and the exhaust stacks ran up in front of the centre-section; a frontal radiator was fitted immediately behind the airscrew. The wings retained the configuration of the original design, but a more efficient aerofoil section was employed and the king-post structures above the upper wing were rectangular. The centre-section had a large cut-out in its trailing portion to improve the pilot’s view upwards. The vertical tail surfaces were re-designed: the F.17 had a larger fin than its predecessor, and its rudder was slightly smaller. The main undercarriage remained unchanged, but the wing-tip floats were braced away from the lower wings by short struts.
  This version of the Campania went into production in 1917, but by the time the completed machines were appearing, the demand for Rolls-Royce Eagle engines was beginning to exceed the supply. An alternative power unit was therefore sought, and the 250 h.p. Sunbeam Maori II was selected. The first Campania to have this engine was N.1006, which had the works number F.22. This machine also had reduced tankage for fuel: the upper tank was smaller, and this became standard for later Campanias. Later still, the 345 h.p. Rolls-Royce Eagle VIII was fitted to some Campanias.
  Both the F.17 and F.22 versions were produced in some numbers, and gave good service on patrol duties both from various home stations during the war and from Archangel during the Russian campaign of 1919.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex.
  Other Contractors: Barclay, Curie & Co., Ltd., Whiteinch, Glasgow.
Power: F.16: 250 h.p. Rolls-Royce Mk. IV (284 h.p. Eagle IV). F.17: 275 h.p. Rolls-Royce Mk. I (322 h.p. Eagle V). F.22: 250 h.p. Sunbeam Maori II; some of the late production Campanias had the 345 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: upper 61 ft 7 1/2 in. Length: F.16, 43 ft 3 5/8 in.; F.17 and F.22, 43 ft 0 5/8 in. Height: 15 ft 1 in. Chord: 6 ft 4 in. Gap: 6 ft 6 in. Stagger: nil. Span of tail: 13 ft.
  Areas: Wings: F.16, 639-8 sq ft; F. 17 and F.22, 627-8 sq ft. Ailerons: each 23-4 sq ft, total 46-8 sq ft. Tailplane: 47 sq ft. Elevators: 28-1 sq ft. Fin: F.16, 14 sq ft; F.17 and F.22, 16-2 sq ft. Rudder: F.16, 22 sq ft; F.17 and F.22, 19-6 sq ft.
  Tankage: Petrol: 88 gallons.
  Armament: One free Lewis machine-gun on Scarff ring-mounting on rear cockpit. Bombs were carried on racks below the fuselage.
  Service Use: H.M. Seaplane Carriers Campania and Pegasus. R.N.A.S. Stations at Portland (later No. 241 Squadron, R.A.F.), Calshot and Dundee. R.A.F. contingent at Archangel.
  Production and Allocation: At least 100 Fairey Campanias were ordered. On October 31st, 1918, the R.A.F. had forty-two Campanias on charge. Of that total, twenty-four Eagle-powered machines were in use for oversea patrols; and two Eagle-Campanias and sixteen Sunbeam-powered machines were at other coastal stations.
  Serial numbers: N.1000-N.1009: built by Fairey. N.1840-N.1889: ordered from Barclay, Curie & Co. N.2360- N.2399: built by Fairey.
  Notes on individual Machines: N.1000: 250 h.p. Rolls-Royce Mk. IV engine. N.1001: 275 h.p. Rolls-Royce Mk. I engine. N.1006: 260 h.p. Sunbeam Maori II engine; was at R.N.A.S. Calshot, December 3rd, 1917. N.2366: 275 h.p. Rolls-Royce Mk. I engine; was at R.N.A.S. Dundee, January 3rd, 1918. N.2367: marked “PC 4”, flown from H.M.S. Campania.
  Costs:
   Airframe without engine, instruments and guns £3,245 0s.
   Engines:
   Rolls-Royce Eagle IV £1,430 0s.
   Rolls-Royce Eagle V £1,721 10s.
   Rolls-Royce Eagle VIII £1,622 10s.
   Sunbeam Maori £1,391 10s. '

Fairey F.128 (Fairey III) and Fairey IIIA

  THE second of the two experimental floatplanes built by the Fairey company in 1917 was known as the F.128 or N.10: it owed the latter designation to its official serial number. The two machines were built at the same time.
  The F.128 was designed as a two-seat patrol seaplane, and had a more powerful engine than the smaller F.127. The 260 h.p. Sunbeam Maori II was installed in the F.128, and there was a radiator block on each side of the engine. The machine had equal-span wings with two-bay bracing; the mainplanes could be folded, and the Fairey Patent Camber Gear was fitted. The fuselage was structurally identical to that of the F.127, and the same tailplane, elevators and rudder were used; the fin of the F.128 was larger than that of the smaller machine.
  The F.128 was the patriarch of the line of Fairey Series III aircraft, and actually had the designation Fairey III. After its tests as a seaplane, N.10 underwent modification at the end of 1917 and reappeared as a landplane. A simple vee undercarriage replaced the floats, and the radiator was installed as a single frontal surface immediately behind the airscrew. In this modified form the machine was redesignated Fairey IIIA.
  The Fairey IIIA went into production for the R.N.A.S., and was intended for use as a ship-borne two-seater, doubtless to be a replacement for the well-tried but obsolete Sopwith 1 1/2-Strutter. The Armistice prevented the IIIA from showing its paces in action, and it saw no wide-scale service with the R.A.F. Other forms of undercarriage were fitted to the IIIA, among them a plain skid undercarriage which had no wheels but carried a hydrovane after the fashion of the Sopwith Pups and 1 1/2-Strutters with which experiments were carried out at the Isle of Grain.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex.
  Power: 260 h.p. Sunbeam Maori II.
  Weights (lb) and Performance:
Fairey III Fairey IIIA Fairey IIIA
No. of Trial Report - N.51 M.220
Date of Trial Report September 14th, 1917 December 10th, 1917 July, 1918
Type of airscrew used on trial F.A.4476 F.A.4476 A.B.4475M
Weight empty 2,970 2,532 2,690
Military load 224 224 449
Crew 360 360 360
Fuel and oil 605 578 446
Weight loaded 4,159 3,694 3,945
Maximum speed (m.p.h.) at
sea level 104 109-5 -
6,500 ft 97 107 -
10,000 ft 94-5 104 97
m. s. m. s. m. s.
Climb to
2,000 ft 3 45 - - - -
5,000 ft 9 10 7 05 - -
6,500 ft 12 35 10 00 14 00
10,000 ft 23 30 17 40 26 00
Service ceiling (feet) 14,000 15,000 13,500
Endurance (hours) 41 41 -

  Dimensions: Span: 46 ft 2 in. Length: Fairey III, 36 ft; Fairey IIIA, 31 ft. Height: Fairey III, 11 ft 10 in.; Fairey IIIA, 10 ft 8 in. Chord: 5 ft 6 in. Gap: 5 ft 7 in. Stagger: nil. Span of tail: 13 ft.
  Areas: Wings: 476 sq ft. Ailerons: each 16-5 sq ft, total 66 sq ft. Tailplane: 34-2 sq ft. Elevators: 34-2 sq ft. Fin: 9-8 sq ft. Rudder: 9-8 sq ft.
  Tankage: Petrol: 76 gallons.
  Armament: One Lewis machine-gun on Scarff ring-mounting on rear cockpit. Bombs could be carried on external racks.
  Production and Allocation: See under Fairey IIIB.
  Serial Numbers: Fairey III and IIIA prototype: N.10. Production IIIAs: N.2850-N.2899.



Fairey IIIB

  THE Fairey IIIA was followed by the Fairey IIIB, a two-seat seaplane designed for bombing duties: it was regarded as falling within the Admiralty class N.2B. The IIIB had the same fuselage and horizontal tail surfaces as the III and IIIA, but the wing area was increased, larger floats were fitted, and increased vertical tail surfaces used. The upper wing had large extensions, braced from king-posts above the outer interplane struts; the wings could be folded, and the Fairey Patent Camber Gear was fitted.
  Ailerons were fitted to the upper wing only. The engine was again the 260 h.p. Sunbeam Maori II, and a frontal radiator similar in shape to that of the IIIA was used.
  The Fairey IIIB went into small-scale production, and a few examples had reached some seaplane stations before the Armistice. The type remained in service for a relatively short period, during which its principal duty was the making of mine-spotting patrols.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex. Power: 260 h.p. Sunbeam Maori II.
  Dimensions: Span: upper 62 ft 8 15/16 in, lower 44 ft 8 7/16 in. Length: 37 ft 1 in. Height: 14 ft. Chord: 5 ft 6 in.
Gap: 5 ft 7 in. Stagger: nil. Dihedral: 1° 30'. Incidence: 4° 30'. Span of tail: 13 ft.
  Areas: Wings: 570 sq ft. Ailerons: each 23 sq ft, total 46 sq ft. Tailplane: 34-2 sq ft. Elevators: 34-2 sq ft. Fin: 12-4 sq ft. Rudder: 12-4 sq ft.
  Weights and Performance.: No. of Trial Report: N.M.107. Date of Trial Report: February 21st, 1918. Type of airscrew used on trial: F.A.4441. Weight empty: 3,258 lb. Military load: 681 lb. Crew: 360 lb. Fuel and oil: 593 lb. Weight loaded: 4,892 lb. Maximum speed at 2,000ft: 95m.p.h.; at 6,500ft: 90 m.p.h.; at 10,000 ft: 81 m.p.h. Climb to 2,000 ft: 4 min 10 sec; to 6,500 ft: 17 min 50 sec; to 10,000 ft: 37 min 50 sec. Service ceiling: 10,300 ft. Endurance: 4 1/2 hours.
  Tankage: Petrol: 76 gallons.
  Armament: One Lewis machine-gun on Scarff ring-mounting on rear cockpit. The total bomb load was apparently about 600 lb, and the bombs were carried on racks suspended under the fuselage.
  Service Use: Seaplane station, Westgate.
  Production and Allocation: The Fairey Aviation Co. built twenty-five Fairey IIIBs. The official statistics for the aircraft on charge with the R.A.F. on October 31st do not differentiate between the Fairey IIIA and IIIB. On that date, the R.A.F. had a total of seventy machines of both types:. two were at coastal stations, twelve were at other units, thirty-six were at Aircraft Acceptance Parks and with contractors, and twenty were in store.
  Serial Numbers: N.2230-N.2259: ordered as IIIBs, but some delivered as IIICs. N.9234.



Fairey IIIC

  THE Fairey IIIB was closely followed by the IIIC, which was probably the best British seaplane of its day, but which arrived too late to give any operational service before the Armistice. It had the same fuselage and float undercarriage as all its predecessors, but reverted to the original equal-span wings of the Type III. The tail unit was identical to that of the IIIB.
  The IIIC had the magnificent Rolls-Royce Eagle VIII engine, and it was to its power plant that the machine owed its fine performance. Radiators were mounted on each side of the fuselage beside the pilot’s cockpit. The opportunity was taken to fit large fuel tanks, and these gave the IIIC a maximum endurance of six hours. It was essentially a reconnaissance and escort-fighter seaplane, but there can be no doubt that it could have lifted a worthwhile load of bombs had it been required to do so.
  It seems probable that the first IIIC, N.2246, was a converted IIIB, and it is equally probable that machines originally ordered as IIIBs were delivered as IIICs. In September, 1918, N.2246 left the Fairey company’s works for the Isle of Grain experimental station, where it underwent its official trials. Apparently it was despatched in such haste that no airscrew was sent with it, for consideration was given to the fitting of a four-bladed airscrew which had belonged to a D.H.4. The official tests were ultimately completed with a suitable airscrew.
  Production machines were just beginning to appear in November, 1918, and in that month Great Yarmouth air station received its first IIIC. The IIIC saw operational service, however, for it was one of the types which formed the equipment of the North Russian Expeditionary Force in 1919.
  The Fairey IIIC survived in service for a short time, but it was replaced by the more powerful IIID after a year or two. In the years immediately after the war, experimental modifications of the type appeared: one had a ski undercarriage, another had amphibian landing gear.


SPECIFICATION
  Manufacturers: The Fairey Aviation Co., Ltd., Hayes, Middlesex.
  Power: 375 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: 46 ft 1 1/4 in. Length: 36 ft. Height: 12 ft 1 3/4 in. Chord: 5 ft 6 in. Gap: 5 ft 3 in. Stagger: nil. Dihedral: 1° 04'. Incidence: 4° 30' at centre-section, 4° 22' 30" at inner struts, 4° 15' at outer struts. Span of tail: 13 ft.
  Areas: Wings: 476 sq ft. Ailerons: each 16-5 sq ft, total 66 sq ft. Tailplane: 34-2 sq ft. Elevators: 34-2 sq ft. Fin: 12-4 sq ft. Rudder: 12-4 sq ft.

Weights (lb) and Performance:
Flight condition Light load Medium load Normal load Overload
No. of Trial Report N.M.238A N.M.238 N.M.238 N.M.247
Date of Trial Report December 9th, 1918 October 26th, 1918 October 24th, 1918 March, 1919
Type of airscrew used on trial F.A.6194 F.A.6194 F.A.6194 F.A.6952
Weight empty 3,392 3,392 3,392 3,549
Military load 170 170 170 247
Crew 360 360 360 360
Fuel and oil 350 678 878 883
Weight loaded 4,272 4,600 4,800 5,039
Maximum speed (m.p.h.) at
2,000 ft 110-5 - 110-5 101
6,500 ft 107 105 107 95-5
10,000 ft 103-5 101 102'5 -
m. s. m. s. m. s. m. s.
Climb to
2,000 ft 2 20 2 10 2 20 3 40
6,500 ft 8 00 8 30 9 30 16 30
10,000 ft 14 15 17 30 18 00 44 00
Service ceiling (feet) 17,000 15,400 15,000 9,100
Endurance (hours) 2 4 5 1/2 5

  Tankage: Petrol: 120 gallons.
  Armament: One fixed forward-firing Vickers machine-gun, synchronised to fire through the airscrew; one Lewis machine-gun on Scarff ring-mounting on rear cockpit; 250 rounds for the Vickers gun, three 97-round drums for the Lewis. Bombs could be carried on racks under the fuselage.
  Service Use: No. 229 Squadron, Great Yarmouth, and at Felixstowe. Russia: aircraft carrier H.M.S. Pegasus with North Russian Expeditionary Force at Archangel.
  Serial Numbers: N.2246 and N.2255; between and about N.9235 and N.9255.

Felixstowe F.1

  JOHN CYRIL PORTE was a Lieutenant in the Royal Navy when, in 1909, he began to experiment with a glider on Portsdown Hill, near Portsmouth. Two years later he was invalided out of the Service with tuberculosis. His disability did nothing to diminish his enthusiasm for flying; rather it seemed to increase it, and by 1912 he was appointed technical director and designer of the British Deperdussin Company. He had learned to fly on a Deperdussin monoplane at Rheims, and his Aviator’s Certificate, dated July 28th, 1911, was No. 548 of the Aero Club de France.
  From then until the Deperdussin company’s flying school at Hendon was forced to close down in August, 1913, Porte became well-known as an excellent pilot. Later that year he became associated with Captain Ernest C. Bass, who, on behalf of White & Thompson, Ltd., acquired the British rights for the products of the Curtiss Aeroplane Company of Hammondsport, New York, U.S.A. In October, 1913, Glenn Curtiss personally delivered one of his latest flying boats to Bass at Brighton: the machine was housed in a canvas hangar which had been erected by Magnus Volk. At Brighton, the Curtiss flying boat was flown by J. D. Cooper, and his passengers included E. C. Gordon England and John Porte.
  Porte was so impressed by the flying boat and its potentialities that he resigned his position as test pilot of the White & Thompson Co., Ltd., in 1914 and went to join Curtiss at Hammondsport. Curtiss had been commissioned by Rodman Wanamaker to design a flying boat capable of flying across the Atlantic, with the intention of competing for the prize of £10,000 which had been offered by the Daily Mail in 1913 for the first trans-Atlantic flight.
  The flying boat was named America and was the precursor of the Curtiss H.4 type which was used by the R.N.A.S. during the war. The original America had a wing span of 72 feet, and was powered by two 90 h.p. Curtiss engines; there was tankage for 300 gallons of petrol and 25 gallons of oil. An enclosed cabin was provided for the crew of two. Porte was to have been one of those two, but just when America was completed the war began in Europe. He returned to England at once and rejoined the Navy: he was at once made a Squadron Commander in the R.N.A.S. At his instigation the Admiralty bought two flying boats of the America type which, when delivered, were given the official serial numbers 950 and 951. These boats were delivered by November, 1914, and were sent to Felixstowe for trials. The results were regarded as promising and a few more Curtiss flying boats were ordered; after further trials an order was placed in March, 1915, for fifty machines of similar design but with more powerful engines. These aircraft were delivered in the second half of 1915 and were officially designated Curtiss H.4.
  In September of that year, Squadron Commander Porte was given the command of the R.N.A.S. Station at Felixstowe. By that time he had flown the America boats operationally and was aware of their shortcomings. He had therefore set about the task of modifying and improving them in an endeavour to produce a truly seaworthy and usable flying boat. In this work he was ably assisted by his Chief Technical Officer, Lieutenant J. D. Rennie.
  The first experiments had been carried out early in 1915, using No. 950, one of the original America boats purchased by the Admiralty. This had a 30-foot hull, which was modified by the addition of wide longitudinal fins which ran from near the bows to the single step, which was under the C.G. The original lifting tail was given negative camber to improve longitudinal stability.
  This hull was not too satisfactory in rough weather, and a second was constructed for the Curtiss flying boat No. 1230. This hull had longer, narrower fins which ran farther aft, for the step was under the rear spar of the lower mainplane; the tail portion of the hull was rounded and had a concave curve on its underside. This caused excessive suction, and take-off with this hull was very difficult. Overall length of No. 1230’s hull was 32 feet 7 1/2 inches, but a different method of construction enabled it to be made 300 lb lighter than that of No. 950. Its lightness was obtained at the expense of strength, however, and it failed after several landings.
  A third hull, 32 feet 4 inches long, was made for the Curtiss H.4 No. 3545. The tail portion was two feet longer than that of No. 1230, and the hull resembled No. 950 in a general way. The forebody was slightly longer and the longitudinal fins were wider, whilst the underside of the tail portion was flat.
  The fourth experimental hull was fitted to the Curtiss H.4 No. 3569, and was 32 feet 2 inches long. It was fundamentally similar to No. 3545, but had a much more pronounced vee bottom. The available power (presumably a nominal 200 h.p.) was insufficient to lift the flying boat off the water, so a step was added five feet aft of the C.G.; the machine then took off at a loaded weight of 4,200 lb. Landing was easy and comfortable, thanks to the vee bottom, but the position of the step so far behind the C.G. demanded considerable physical exertion by the pilot at take-off. To relieve the pilot, the step was moved three feet forward.
  The fifth hull differed from all its predecessors, both in construction and appearance. It was a completely new design and was in every sense the prototype of all the succeeding “F” boats. The machine to which it was fitted was No. 3580. The hull was named Porte I, and subsequently the aircraft was designated F. 1. The basic structure of the hull differed little from that of contemporary landplanes, for it was a cross-braced wooden box girder, to which a vee planing bottom and longitudinal fins had been added. This hull was 36 feet 2 inches from stem to stern, and originally had a single step below the rear spar; the bows were more fully flared than those of earlier hulls. The aircraft was powered by two 150 h.p. Hispano- Suiza engines.
  Tail drag made take-off difficult, so a second step was added 7 feet 6 inches from the stern; and finally a third step was fitted between the first two. This hull proved itself superior in every way to its predecessors: the improved bow design prevented the shipping of water, and take-off and landing performance was excellent. The cockpit was open, whereas all the preceding experimental hulls had had enclosed cabins.
  The F. 1 had the wings and tail unit of a normal Curtiss H.4 flying boat, but the Hispano-Suiza engines were a special installation, for the standard R.N.A.S. machines had two 100 h.p. Anzani radial engines.


SPECIFICATION
  Manufacturers: Seaplane Experimental Station, Felixstowe.
  Power: Two 150 h.p. Hispano-Suiza.
  Dimensions: Span: upper 72 ft, lower 46 ft. Length of hull only: 36 ft 2 in. Chord: 7 ft. Gap: 7 ft 6 in.
  Serial Number: 3580.

Felixstowe F.2A and F.2C

  AFTER the success which had been achieved with the F.1, Squadron Commander Porte extended his A experiments to larger hulls. He began work with No. 8650, the first Curtiss H.12 flying boat to be delivered to the R.N.A.S.
  The H.12 was generally similar in design to the H.4, but was considerably larger. On its appearance in service it was named the Large America, whereafter the H.4 was known as the Small America. As delivered, the H.12 had two 160 h.p. Curtiss engines, but when Porte began his experiments with No. 8650, these proved to be insufficiently powerful to get the boat off the water at a weight of 8,700 lb. The Curtiss engines were replaced by two 250 h.p. Rolls-Royce engines. Take-off was then accomplished, but with difficulty, owing to lack of buoyancy forward. The hull of the H.12 was weak structurally, yet these Large Americas did some excellent work when powered by two Rolls-Royce Eagle engines of later marks.
  It was obvious that the F.1 hull was superior to that of the Curtiss H.12, so it was decided to build a hull similar to the Porte I but large enough to take the wings of the Large America. The new hull was known as the Porte II, and the aircraft to which it was fitted was designated F.2. It was the prototype of the line of successful F-boats, which gave such distinguished service up to and beyond the Armistice.
  The F.2’s hull was almost identical to that of the F.1 in outline but was larger: it was 42 feet 2 inches long, and its maximum beam was 10 feet. It had only two steps, and these were applied outside the skin of the hull, as had been done on the F.1. The forward step was directly under the rear spar of the wings, and the rear step was 6 feet 5 inches farther aft. Structurally the hull was basically a cross-braced box girder, as opposed to the original Curtiss boat-built hull. Forward of the rear spar of the centre-section the sides of the hull were braced as N-girders; elsewhere the cross-bracing was by means of wires or tie-rods. The spars of the lower centre-section were integral parts of the hull box girder. The bottom longerons were spaced by solid mahogany members known as floors: these floors were inverted triangles whose downwards-pointing apices formed the ridge of the keel. Athwartships they were unbroken, but for two- thirds of their depth they were notched out to fit over the solid keelson, which was correspondingly notched out for one-third of its depth and ran from bows to sternpost as a continuous structural member.
  As on the F.1, hull, the side fins were built on to the outside of the basic hull structure. To give adequate support to the planking between floors, intermediate timbers of rock elm ran from chine to chine. The double-diagonal planking consisted of an inner skin of 1/8-inch cedar and an outer of 3/16-inch mahogany separated by a layer of varnished fabric. This planking was applied to the hull bottom, whilst the fin tops and the hull sides were planked with three-ply; abaft the rear spar the hull sides were fabric-covered and had a solid mahogany washboard along the lower longerons. The top of the hull was also fabric-covered, with the exception of the portion in front of the cockpit, which was planked with plywood. A semi-enclosed cabin was provided for the crew. The shape of the hull was such that the tail was carried high: this served not only to keep the tailplane out of spray when taxying, but also to give the waist gunners a good field of fire towards the rear.
  The wings were similar to those of the Curtiss H.12. The upper mainplanes had long extensions, the landing wires for which ran from rectangular pylons above the outermost interplane struts: these pylons were faired over with fabric, but the resulting vertical surfaces had no designed aerodynamic function. There were three bays of struts outboard of the engines.
  The Porte II hull proved to be an excellent design, and the F.2 was strong and seaworthy. One of the great advantages of the Porte design of hull was its structural simplicity, which enabled it to be made by firms which had no experience of boat-building. The type was placed in production with several contractors in 1917, but delays occurred: an official decision to change from the original 23-inch gun-ring to one of 20-inch diameter necessitated structural modifications and held up. production.
  The production machines had two 360 h.p. Rolls-Royce Eagle VIII engines, and embodied other minor modifications. They were designated F.2A. Deliveries began to be made at the end of 1917, and from early 1918 until the Armistice the type was in use at almost every flying-boat station of the R.N.A.S. This widespread use gave some trouble with the early F.2A hulls, for the machine had been designed to operate from sheltered harbours, and exposure to unfavourable sea conditions led to deterioration of the hull. The original 5-inch planks on the hull bottom warped, the plywood on the fin tops and sides opened up, and the fabric rotted. Narrower planks were therefore fitted, double-diagonal planking of mahogany and cedar was applied to the fin tops, and the sides were either given single planking with fabric covering or were completely planked with Consuta, the special material invented by S. E. Saunders, Ltd. It consisted of plywood sewn with copper into large sheets. Other structural modifications had to be made to meet the rigours of operational service.
  The estimated life of the F.2A under mooring conditions was six to eight months, but where hangar and slipway facilities were available the boats were taken ashore on wheeled trolleys specially made to conform to the shape of the hull bottom. Manhandling these relatively fragile wooden hulls could be a tricky business, and the beaching crew had to be both numerous and skilful. A vivid account of a launching, take-off, flight, and landing and beaching of an F.2A is to be found in pages 352-357 of The Story of a North Sea Air Station, by C. F. Snowden Gamble.
  The flying boats of Felixstowe air station are probably best remembered for their connexion with the famous “Spider Web” patrol. This patrol was flown as an octagonal figure centred on the North Hinder Light Vessel. Sixty nautical miles across, it enabled some 4,000 square miles of sea to be systematically searched: this area lay across the most possible tracks of enemy submarines. The five flying boats which began to operate the Spider Web patrol on April 13th, 1917, made twenty-seven patrols before the month was out, sighted eight U-boats and bombed three of them, and had one engagement with enemy destroyers.
  It was into action of this tradition that the F-boats came. Unfortunately, the shortage of Rolls-Royce engines severely hampered the production of the big flying boats. In May, 1917, when the requirements of aircraft for 1918 were under consideration, it was estimated that 180 flying boats of the Large America type would be needed. The Government’s decision to double the size of the British air services, taken in July, 1917, increased that number to 426. In view of the fact that the average life of a flying boat was six months, the total requirements for the full year of 1918 amounted to 852 flying boats. This figure was impossible of achievement, but the net requirements were reduced to 234 upon the U.S. Navy Department’s agreement to equip five seaplane stations and upon the decision to build at Malta the sixty boats required for the Mediterranean area.
  By March, 1918, 161 F.2As had been ordered, but only ten were in service. The required total of 234 was to consist of both F.2As and the later F.3s, but it was never realised. A review of the production of Rolls-Royce engines showed that sufficient Eagles would be available to equip only 170 Large America boats by the end of May, 1918. Even that estimate proved to be over-optimistic, for only 104 F-boats had been delivered by that date.
  All the big twin-engined Porte-designed flying boats were known as Large Americas, and it is difficult to distinguish one type from another or from the original Curtiss H.12 in the official history. The F.2A was the best-known boat of the series, partly because it was a better machine than the F.3 and partly because the F.5 arrived too late to see service on a large scale.
  The R.N.A.S. air station at Great Yarmouth received the first of its F.2As early in February, 1918, but trouble was experienced with the fuel system. The main fuel tanks were in the hull, and petrol was pumped to a gravity tank in the centre-section by means of wind-driven pumps; the carburettors were fed from the gravity tank. The total length of piping in the system was therefore considerable, and most of the faults occurred in the fuel pipes. On February 5th, 1918, the first patrol to be attempted by a Great Yarmouth F.2A was balked by a partial choke in a petrol pipe, and eleven days later the same machine, N.4511, was forced down one hour out from base with the gravity tank filter clogged. The crew were picked up by H.M.S. Glowworm, and owed their rescue to a home-made precursor of the dinghy radio developed in World War II. Leading Mechanic Walker had been experimenting at Yarmouth with a 5-foot linen box kite carrying an aerial, and on this occasion he had his apparatus with him on board N.4511. From its signals the position of the flying boat was fixed, and H.M.S. Glowworm found it only eight miles down wind from the position she was given.
  The F-boats from Yarmouth and Felixstowe had many brushes with the Brandenburg W.12 and W.29 seaplane fighters from the enemy seaplane stations at Borkum, Norderney and Zeebrugge. The boats usually gave as good as they got, for their heavy defensive armament and the determination of their crews made up for their lack of speed and manoeuvrability.
  On June 4th, 1918, five flying boats led by Captain R. Leckie set out for the Haaks Light Vessel with the one intention of seeking out and fighting enemy seaplanes. The force consisted of four F.2As and one Curtiss H.12: the F.2As were N.4295 and N.4298 from Great Yarmouth, and N.4302 and N.4533 from Felixstowe; whilst the H.12 was 8689 from Felixstowe. But even before the enemy were sighted the petrol feed pipe to one of the engines of N.4533 broke, and the F.2A was forced down. Its pilot (Captain Dickey) could do no more than taxi to Holland, where he beached and burned the machine. The H.12 had set off in hot pursuit of some German machines which had attacked and were intent on harassing the limping N.4533, and the three remaining F.2As were later engaged by a mixed force of fourteen enemy seaplanes. The F.2As fought an action which must rank as a veritable Jutland of the skies, and Leckie led the little force with magnificent audacity. N.4302 was compelled to go down with a broken petrol pipe, and Captain Hodson flew N.4289 on one engine whilst the other was repaired during the combat. The engineer of N.4302, Private Reid, made a temporary repair which enabled the boat to return to Great Yarmouth, despite a damaged wing-tip float.
  At 7.10 p.m. the three F.2As alighted in Great Yarmouth Roads after being airborne just over six hours and fighting one of the greatest air battles of the war, for the enemy lost six seaplanes. But Leckie’s report included the acrid comment: “It is again pointed out that these operations were robbed of complete success entirely through faulty petrol pipes.... It is obvious that our greatest foes are not the enemy, but our own petrol pipes.”
  This action was largely responsible for the general adoption of the gaudy “dazzle-painting” of many F-boats. The F.2A flown by Captain Hodson, N.4289, “was terrible in appearance, painted post-box red, with yellow lightning marks running diagonally across her ... he fondly hoped that this would put the wind up the Hun.” Whether it did that or not is not known, but it left Hodson’s comrades in no doubt about his aircraft’s identity. The first object of the dazzle-painting was to identify the pilot of any particular flying boat, so, at Great Yarmouth, the choice of scheme was left to individual pilots. This produced some bizarre combinations of checks, stripes and zig-zags in bright colours. Felixstowe had a more or less standard (but no less striking) colour scheme for its boats.
  One of the Felixstowe F.2As was experimentally fitted with two “howdah” gun positions on the upper wing. Each contained a gunner and twin Lewis guns on a Scarff ring. The bow gunner also had twin Lewis guns, and it seems probable that the machine was intended to act as an escort fighter for the patrolling F.2As. The experiment was not a success, however, and the idea was abandoned.
  On May 10th, 1918, an F.2A from Killingholme, flown by Captains T. C. Pattinson and A. H. Munday, engaged the Zeppelin L.62 at 8,000 feet over the Heligoland minefields. Captain Munday opened fire from the bow cockpit and Sergeant H. R. Stubbington, the engineer, also brought his Lewis gun to bear on the target. Many hits appeared to be scored, but the flying boat broke an oil feed pipe and had to alight on the sea. The Zeppelin made off due east, losing height and emitting smoke, and soon afterwards blew up and fell in flames.
  A most ambitious scheme in which F.2A flying boats were concerned was the use of lighters, towed by destroyers, as a means of increasing the radius of action of the flying boats. The idea had first been proposed by Squadron Commander Porte in September, 1916. His original design was for a channel-shaped lighter which could be submerged by the flooding of tanks; after the flying boat had been floated into position, the water was blown out of the tanks by compressed air. This raised the flying boat clear of the water, and the lighter was free for towing.
  Orders for four lighters were placed in January, 1917, and the first was successfully tested in the following June. As actually built, the lighter was made to submerge only at the stern and the flying boat was warped aboard. Towing trials promised well, and in September, 1917, a lighter with a flying boat aboard was towed at speeds up to 32 knots. Twenty-five lighters were ordered immediately, a number which was subsequently increased to fifty. The first was delivered in May, 1918, and fifty-one had been delivered by the time of the Armistice.
  One of the chief objects of the use of lighter-borne flying boats was to carry out bombing attacks on the German naval bases in the North Sea, but their first use was to provide advanced take-off facilities for distant reconnaissances in the Heligoland Bight. The first operation of this kind took place on March 19th, 1918, apparently using three of the prototype lighters. At 5.30 a.m. three destroyers towed flying boats to a point off the German coast, and the three boats were airborne by 7 a.m. During their patrol they shot down one of two enemy seaplanes which attacked them, and flew back to their base direct. Next day the operation was successfully repeated, and the towed flying boats were used on several later occasions in 1918. The original intention of using the lighter-borne flying boats to bomb enemy naval bases was abandoned in July, 1918, by which time sufficient progress had been made with long-range bomber landplanes to bring the targets within their radius of action.
  The F.2A remained in service right up to the time of the Armistice. Because its performance was better than that of the F.3 it was chiefly used from stations which covered the sea areas where fighting, anti-Zeppelin work and reconnaissance predominated. The F.3 was used at stations responsible for antisubmarine patrols, for which duty its longer range made it more suitable.
  Many modifications were made to production F.2As: some were incorporated on the production lines; others were made locally at seaplane stations to meet the personal tastes of crews. One of the most noticeable changes Was the absence of the cabin top over the pilots’ cockpits on later F.2As: its removal improved their view considerably, particularly towards the rear, and added a few knots to the speed. Such F.2As began to appear about September, 1918. They also had the sides of the hull planked overall with mahogany or, in the case of the Saunders-built machines, Consuta.
  A further significant modification, incorporated at this time, was the fitting of constant-chord horn-balanced ailerons similar to those of the F.5. This helped to relieve some of the considerable physical strain imposed upon the pilot; protracted patrols could be exhausting in a heavy aircraft which had no balanced controls of any kind. Several pilots went so far as to fit modified flight controls of their own design.
  It is doubtful whether an F.2B variant was ever built, but the designation has been applied to the open-cockpit version of the F.2A. A modified type known as the F.2C was, however, built and flown. It had a lightened hull with modified steps and new contours for the forebody. The bow gunner’s cockpit was farther back from the bows than on the F.2A, and the cockpit for the pilots was open. A deep top-decking was fitted to the hull, and there were no waist hatches behind the wings.
  Although the F.2C did not go into production, it was used operationally by the War Flight at Felixstowe seaplane station. On July 24th, 1917, Felixstowe sent out a patrol of five flying boats, the greatest number despatched together up to that time. The patrol was led by Wing-Commander Porte himself in the F.2C. Near the North Hinder Light Vessel, the periscope of a U-boat was sighted. Three of the flying boats dropped a total of five 230-lb bombs on the submarine and sank it: two of the bombs were, dropped by the F.2C, which thus played a leading part in the destruction of the enemy submarine U.C.1.
  The F.2C was fitted with an experimental bomb-dropping gear which was actuated by compressed air instead of the simple Bowden cable mechanism which was used on the other F-boats. The compressed air gear was elaborate and not wholly reliable: at least one enemy submarine owed its escape to the gear’s defection one day late in September, 1917, when the F.2C was being flown by Squadron Commander T. D. Hallam, D.S.C. He attacked a surfaced U-boat, but his bombs failed to leave the racks.


SPECIFICATION
  Manufacturing Contractors: The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W.; hulls made by May, Harden & May, Southampton Water. S. E. Saunders, Ltd., East Cowes, Isle of Wight (built 100 F.2As). The Norman Thompson Flight Co., Bognor Regis (F.aAs built at the Littlehampton works; production may have consisted of hulls only).
  Power: F.2A: two 345 h.p. Rolls-Royce Eagle VIII. F.2C: two 275 h.p. Rolls-Royce Mk. II (322 h.p. Eagle VI).
  Dimensions: Span: upper (F.2A) 95 ft 7 1/2in.; (F.2C) 95 ft; lower (F.2A) 68 ft 5 in. Length: F.2A, 46 ft 3 in.; F.2C, 46 ft. Height: 17 ft 6 in. Chord: 7 ft 1 in. Gap: 7 ft 1 in. Stagger: nil. Dihedral: 1°. Incidence: 4° 15'.
  Areas: Wings: F.2A, 1,133 sq ft. F.2C, 1,136 sq ft.
  Tankage: F.2C: petrol, 220 gallons; oil, 16 gallons.
  Armament: Four Lewis machine-guns were usually carried: one was on a Scarff ring-mounting on the nose cockpit; another was mounted in the upper rear cockpit behind the wings; and there was one in each waist position. Sometimes a double-yoked pair of Lewis guns were carried in the bow and upper rear cockpits, and frequently an additional Lewis was mounted on top of the pilots’ cockpit canopy. Two 230-lb bombs were carried in racks under the lower mainplane.
   One experimental F.2A had a “howdah” gunner’s cockpit let into each upper mainplane above the first pair of interplane struts outboard of the engines. Each gunner had a pair of double-yoked Lewis guns on a Scarff ring-mounting.
   F.2C: twin Lewis guns on Scarff ring-mounting on bow cockpit. Two 230-lb bombs under each lower wing.
  Service Use: Flown from R.N.A.S. seaplane stations at Felixstowe, Great Yarmouth, Killingholme, Calshot, Dundee, Scapa Flow and Tresco, Scilly Isles (later No. 234 Squadron); No. 230 Squadron, R.A.F.
  Distribution: On October 31st, 1918, the R.A.F. had fifty-three F.2As on charge. All were at seaplane stations in the United Kingdom; none were overseas.
  Serial Numbers: N.4080-N.4099: ordered as F.2As from S. E. Saunders; some delivered as F.5s. N.4280-N.4309: ordered as F.2As from S. E. Saunders. N.4430-N.4479: ordered as F.2As from S. E. Saunders; some delivered as F.5s. N.4480-N.4504: ordered as F.2As from the Aircraft Manufacturing Co. (May, Harden & May); some delivered as F.5s. N.4510-N.4519: built by the Aircraft Manufacturing Co. (May, Harden & May). It was at one time intended to fit Sunbeam engines to these ten F.2As. N.4530-N.4554: built by the Aircraft Manufacturing Co. (May, Harden & May). Between N.4560 and N.4568 were F.2As. It is believed that N.4584 was an F.2A. N.65: the F.2C.

Weights (lb) and Performance:
Type F.2A F.2C
No. of Trial Report N.M. 125 -
Date of Trial Report March, 1918 June 23rd, 1917
Type of airscrew used on trial A.B.665 A.B.665
Weight empty 7,549 6,768
Military load 585 402
Crew 720 720
Fuel and oil 2,124 2,350
Weight loaded 10,978 10,240
Maximum speed (m.p.h.) at
2,000 ft 95-5 98
6,500 ft 88-5 94
10,000 ft 805 91
m. s. m. s.
Climb to
2,000 ft 3 50 4 50
6,500 ft 16 40 18 20
10,000 ft 39 30 38 00
Service ceiling (feet) 9,600 10,300
Endurance (hours) 6 -

  Notes on Individual Machines: F.2As used at Great Yarmouth: N.4283, N.4289, N.4295, N.4298, N.4303, N.4305,
N.4511, N.4512, N.4549, N.4550. F.2As used at Felixstowe: N.4302 and N.4533. F.2As used at Killingholme: N.4287, N.4290, N.4291, N.4516. N.4545 had the later open cockpit for the pilots.
  Costs:
   F.2A flying boat including hull and trolley, but without engines, instruments and guns £6,738 0s.
   Rolls-Royce Eagle VIII engine, each £1,622 10s.



Felixstowe F.3

  ALTHOUGH the F.3 was almost indistinguishable from the F.2A and was produced in larger numbers, it was not so well-liked as the earlier design. The F.3 was a rather larger flying boat and could carry double the load of bombs on the same power, but it did not handle so well as the F.2A.
  The hull was very similar to that of the F.2A, but was about three feet longer. The “fuselage-type” construction was again employed, but an unfortunate change was made in the design of the floors: instead of being continuous athwartships, as on the F.2A, they were made in two halves, each of which was rebated into the keelson on either side. This produced an unsatisfactory structure, and the planking sprang readily along the garboard strake, with subsequent leakage. Intermediate timbers were later introduced to support the planking, but the F.3 hull was never so satisfactory as that of the F.2A. The hull was planked in the same way as that of the F.2A. As on the earlier aircraft, the birch three-ply covering of the fin tops was later replaced by double-diagonal planking.
  The wings were of greater span and chord, but the interplane bracing was of the same configuration as that of the F.2A. The leading edge of the upper wing was slightly recessed immediately behind the airscrews. On the prototype F.3 a vertical surface was fitted between the first pair of interplane struts outboard of the engines, but this feature was not reproduced on later machines.
  The prototype, N.64, was tested with two 320 h.p. Sunbeam Cossack engines, but production F.3s had two Rolls-Royce Eagle VIIIs which drove opposite-handed airscrews. The tail-unit was indistinguishable from that of the F.2A; The wing-tip floats were the same as those of the earlier type, and therefore did not quite reach the trailing edge of the lower wing. It appears that N.64 was used operationally, for an F.3 was reported in use with Felixstowe’s War Flight as early as July, 1917, long before production F.3s were available. (This first F.3 survived until May 15th, 1918, when it was written off at Felixstowe.)
  The F.3 was ordered in such quantities that it seems that it was preferred to the F.2A, possibly because of its larger bomb load. The allocations of serial numbers for batches of F.2As and F.3s (though by no means a reliable guide) seem to indicate that orders for the two types of flying boat were placed simultaneously. Production was begun in 1917 by several contractors.
  There are indications that Porte and his colleagues had misgivings about the official decision to produce the F.3 in such quantities; and indeed the decision’s effect was to reach beyond the type F.3 itself, for it later affected the F.5 also. By March, 1918, orders for F.3s totalled 263; only one was in service at that time.
  The shortage of Rolls-Royce engines had an adverse effect upon the production of F.3s just as it had held up the F.2A. It had been known as early as the spring of 1917 that the demands of home seaplane stations would absorb all the flying boats that could be built in Britain: this situation is analysed in some detail in the history of the F.2A. In the Mediterranean there was, however, a clamant need for flying boats for anti-submarine patrols, and it was therefore decided to build F.3s at Malta. Local labour was employed. The men, who were expert boat-builders, had no difficulty in making the simple Porte-type hulls, and Maltese women were employed as fabric workers under the supervision of Lady Methuen, the wife of the Governor of the island. The first Maltese-built F.3 was completed in November, 1917, and seventeen more were built there during the following twelve months.
  Because of its greater range and inferior performance relative to the F.2A, the F.3 was used from seaplane stations responsible for anti-submarine patrols rather than fighting. The type had the added distinction of serving in the Mediterranean; one accompanied the Allied fleet in its attack upon the Albanian port of Durazzo on October 2nd, 1918.
  The flight condition of the F.3 depended upon the nature of its duty and upon the duration of the flight. It was loaded to four different flight conditions, as the performance tables show.
  In the experimental field, an F.3 was used to test servo-operated controls; and another was fitted with the automatic landing device invented by Major A. Q. Cooper. A long arm, connected to the pilot’s control column by an elastic linkage, was allowed to trail below the aircraft in flight; on striking the water the arm moved the control column backwards and automatically rounded-out the boat’s approach. Success was not achieved at once, but fully automatic landings were ultimately accomplished.
  The prototype F.3 had flown as early as February, 1917, and the production machines were contemporary with the production F.2As. After the Armistice, the F.3 was withdrawn in favour of the F.2A and the F.5, and was finally declared obsolete in September, 1921.


SPECIFICATION
  Manufacturing Contractors: Dick, Kerr & Co., Ltd., Preston; The Phoenix Dynamo Manufacturing Co., Ltd., Bradford; Short Brothers, Ltd., Rochester; Dockyard Constructional Unit, Malta.
  Power: Prototype: two 320 h.p. Sunbeam Cossack. Production: two 345 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: upper 102 ft, lower 74 ft 2 in. Length: prototype 45 ft, production 49 ft 2 in. Height: prototype 18 ft, production 18 ft 8 in. Chord: 8 ft. Gap: 8ft 6in. Stagger: nil. Dihedral: 1° 30'. Incidence: 4°. Span of tail: 22 ft. Airscrew diameter (Eagles): 10 ft.
  Areas: Wings: 1,432 sq ft. Ailerons: each 65 sq ft, total 130 sq ft. Tailplane: 118 sq ft. Elevators: 67 sq ft. Fin: 37-2 sq ft. Rudder: 30-3 sq ft.
  Tankage: Petrol, maximum: 400 gallons. Oil: 15 gallons.
  Armament: One Lewis machine-gun on rotatable mounting on bow cockpit; one on cockpit aft of wings; and one in each waist position. Four 230-lb bombs were carried in racks under the lower wings.
  Service Use: Used from seaplane stations at Felixstowe, Cattewater, Houton Bay, Scilly Isles, and flown in the Mediterranean, probably from Taranto.
  Distribution: On October 31st, 1918, the R.A.F. had ninety-six F.3 flying boats on charge. Eighteen were attached to the Grand Fleet for patrol duties; twenty-six were at various seaplane stations and three others were at non-operational stations in the United Kingdom; thirteen were in the Mediterranean; one was at an Aeroplane Repair Depot; eighteen were with contractors; and seventeen were in store.
Weights (lb) and Performance:
Engines Two 320 h.p. Sunbeam Cossack Two 345 h.p. Rolls-Royce Eagle VIII
Flight condition - Light load Medium load Normal load Overload
No. of Trial Report - N.M.155 N.M.155 N.M.155 N.M.155
Date of Trial Report February 9th, 1917 and April 19th, 1917 April 26th, 1918 April 26th, 1918 April 29th, 1918 May 7 th, 1918
Type of airscrew used on trial A.B.586 A.B.665 A.B.665 A.B.665 A.B.665
Weight empty 8,270 7,958 7,958 7,958 7,958
Military load Nil 238 1,317 1,461 1,461
Crew 900 720 720 720 720
Fuel and oil 2,455 836 2,089 2,096 3,142
Weight loaded 11,625 9,752 11,084 12,235 13,281
Maximum speed (m.p.h.) at
400 ft 88-5 - - - -
2,000 ft - 93 92,5 91 90
6,500 ft - 91-5 - 86 87
10,000 ft - 87-5 - - -
m. s. m. s.
Climb to
2,000 ft 3 00 3 10 4 00 5 25 7 50
6,500 ft 27 00 12 55 18 00 24 00 41 00
10,000 ft 60 00 24 50 41 30 - -
Service ceiling (feet) - 12,500 10,000 8,000 6,000
Endurance (hours) - 2 1/4 6 6 9 1/2

  Serial Numbers: N.64: prototype F.3. N.4000-N.4049: ordered as F.3s from Short Bros., some delivered as F.5s. N.4100-N.4159: built by Dick, Kerr & Go. N.4160-N.4179: built by Phoenix Dynamo Manufacturing Co. N.4180-N.4229: ordered as F.3s from Phoenix Dynamo Manufacturing Co.; some delivered as F.5s. N.4230- N.4279: built by Dick, Kerr & Co. N.4310-N.4321: built at Malta Dockyard. N.4370: built at Malta Dockyard. N.4400-N.4429: built by Phoenix Dynamo Manufacturing Co.
  Notes on Individual Machines: Used at Tresco, Scilly Isles (later No. 234 Squadron): N.4000, N.4001, N.4002, N.4234, N.4238, N.4240, N.4241, N.4415.



Felixstowe F.5

  THE designation F.5 was applied to two different flying boats. The first was the boat whose serial number was N.90, and was John Porte’s last Felixstowe biplane design.
  The hull was structurally similar to Porte’s earlier hulls, but was rather deeper and had no cabin enclosure for the crew. The sides abaft the mainplanes were fabric-covered and had the usual mahogany washboard along the entire length of their lower edges. The F.5 hull was regarded as the best of the Porte hulls, with the possible exception of that of the Felixstowe Fury, which had the inherent advantage of greater size.
  The wing structure was almost identical to that of the F.3, but the ailerons were horn-balanced and rectangular in shape, whereas those of the earlier F-boats had retained the inverse taper of the ailerons of the original Curtiss design. The trailing edge of the ailerons lay behind that of the upper wing. A different wing section was employed.
  The tail-unit was very similar to that of the F.2A and F.3, but the chord of the tailplane was greater and the surface projected in front of the leading edge of the fin. The rudder had a balancing surface inset into the fin.
  The original F.5 was an excellent flying boat, and would probably have been a much better proposition than the F.3 for large-scale production. However, the F.3 had already been put into production with several manufacturers, and the Ministry of Munitions set its hand against the new jigs and templates which would have been required to produce the F.5.
  A type of flying boat was produced under the designation F.5, but it differed considerably from N.90. The hull was a hybrid in which as many F.3 components as possible were used to produce a hull with approximately the characteristics of the original F.5 design. The hull was planked overall, and this stronger covering together with the modifications made the hull of the production F.5 appreciably heavier than that of the original machine.
  The wings of the production aircraft were identical to those of the F.3, and reverted to the R.A.F. 14 aerofoil section of the earlier boats. However, the modifications necessary to make the wings suitable for production increased their weight; adapters were fitted to accommodate either Rafwires or stranded cables for the interplane bracing; and permanent slinging gear was fitted. Rectangular horn-balanced ailerons similar to those of N.90 altered the shape of the wing-tips.
  The tail-unit was similar to that of N.90: the balanced rudder was retained, and the elevators had horn balances. At the Isle of Grain an F.5 was flown with experimental aileron balances of the “park bench” type, as fitted to the Avro Manchester and Bristol Badger.
  Production F.5s appeared too late for the type to see operational service; none were recorded as on charge with the R.A.F. on October 31st, 1918. Contracts for all types of flying boats were cancelled or reduced after the Armistice, and a number of F.5s went into store, whence they were later withdrawn and reconditioned for the equipment of the R.A.F.’s flying boat units in the years following the Armistice. The type was adopted as the standard Service flying boat.
  With the F-5, the wheel of flying boat design turned full circle, for the type was produced in America, and was the U.S. Navy’s standard flying boat in the early 1920s. The American machines were powered by two Liberty engines of 400 h.p. each, and the aircraft was known as the F-5L. Later F-5Ls had a modified fin and rudder assembly: the leading edge of the fin was rounded, and the rudder had a horn balance. The armament of the F-5L could include a 1 1/2-pounder quick-firing gun, presumably for anti-submarine work.
  In late 1919 the Aeromarine Plane & Motor Company of Keyport, New Jersey, modified two F-5Ls to accommodate twelve passengers in two cabins within the hull, which was provided with circular windows. This conversion was known as the Aeromarine Model 75, and the boats were used on the Key West-Havana route operated by Aeromarine West Indies Airways, Inc. They carried hundreds of prohibition-weary passengers to and from Cuba without incident until the collapse of the operating company in 1923, when the air-mail subsidies were withdrawn.
  A proposal was made in 1920 for the commercial operation of F.5s between the West Indies and Venezuela, but it came to naught.
  Japan bought fifteen F.5s for use by the Imperial Japanese Naval Air Service in 1921. These machines gave excellent service and were particularly useful to the British Air Mission which went to Japan in 1921. The F.5s made a number of commendable long-distance flights, and on several occasions were airborne for more than nine hours.
  In the post-war years, two experimental conversions of the F.5 appeared. The more significant of the two was N.177, otherwise the Short S.2, which had an all-metal hull designed and made by Short Bros.: it was claimed to be the first flying boat in the world to be so equipped. Earlier in point of time was N.178, which had a special hollow-bottom hull made by S. E. Saunders.


SPECIFICATION
  Manufacturing Contractors: The Gosport Aviation Co., Ltd., Gosport; The Aircraft Manufacturing Co., Ltd., Hendon, London, N.W. (May, Harden & May, Southampton Water); Phoenix Dynamo Manufacturing Co., Ltd., Bradford; S. E. Saunders, Ltd., East Cowes, Isle of Wight; Short Bros., Rochester; Canadian Aeroplanes, Ltd., Toronto, Ontario, Canada; U.S. Naval Aircraft Factory, League Island, Philadelphia, Pennsylvania, U.S.A.
  Power: British-built F.5: two 325 h.p. Rolls-Royce Eagle VII; two 350 h.p. Rolls-Royce Eagle VIII. Canadian-built F.5: two 400 h.p. Liberty 12. F-5L: two 400 h.p. Liberty 12.
  Dimensions: Span: upper 103 ft 8 in., lower 74 ft 2 in. Length: 49 ft 3 in. Height: 18 ft 9 in. Chord: 8 ft. Gap: 8 ft 6 in. Stagger: nil.
  Areas: Wings: 1,409 sq ft. Tailplane and elevators: 178 sq ft. Fin: 41 sq ft. Rudder: 33 sq ft.
  Data for F-5L: Weight empty: 8,250 lb. Weight loaded: 13,000 lb. Maximum speed: 87 m.p.h. Climb to 2,625 ft: 10 min. Endurance: 10 hours.
  Armament: One Lewis machine-gun on rotatable mounting on bow cockpit; one in cockpit aft of wings; and one in each waist position. The F-5L had additionally a 1 1/2-pounder quick-firing gun, and could be armed with as many as eleven machine-guns. Four 230-lb bombs were carried on racks under the lower wings.
  Use: Seaplane stations at Felixstowe, Calshot, Mount Batten, Great Yarmouth. No. 230 Squadron, R.A.F. (later No. 480 Flight) Calshot. Navigation Training Flight, Calshot.
  Serial Numbers: N.90: prototype F.5. Some of batch N.4000-N.4049, originally ordered as F.3s from Short Bros.; N.4039, N.4041 and N.4044 known to have been F.5s. Some of N.4080-N.4099, ordered as F.2As from S. E. Saunders; N.4091 known. Some of N.4180-N.4229, ordered as F.3s from Phoenix Dynamo Manufacturing Co.; N.4192 and N.4193 known. Some of N.4430-N.4479, ordered as F.2As from S. E. Saunders; N.4462 and N.4467 known. Some of N.4480-N.4504, ordered as F.2As from the Aircraft Manufacturing Co.; N.4488, N.4497 and N.4499 known. N.4580: built by Saunders. N.4630, N.4634, N.4636 and N.4637: built by Gosport Aviation Co. N.4838 and N.4839.

Felixstowe Fury

  THE Felixstowe Fury of 1918 was John Porte’s most ambitious flying boat design. It was a very large triplane powered by five Rolls-Royce Eagle VII engines, and as soon as its proportions became apparent it was popularly dubbed the Porte Super Baby. Its official name was the Felixstowe Fury, but in its day it was better known by its unofficial title.
  Into the Fury was built all the experience which had been gained with the F.1, F.2 and F.3 hulls, and the Fury hull was regarded as the best of all the Felixstowe hulls built on the Porte principle. It had the same basic structure of four longerons built into a cross-braced box girder, and was planked diagonally with two skins of cedar over an inner longitudinal skin. The keelson and floors were of built-up lattice girder construction, and the bottom was covered with three layers of cedar and mahogany half an inch thick. Great pains were taken to avoid the splitting which occurred at the joints of earlier hulls: the diagonal planking was steamed and bent round the chines and fin tops in order to eliminate the troublesome joints. The vee-bottom of the hull was slightly concave, whereas the F-boats had straight sections of 150° included angle.
  The Fury was originally designed for three Rolls-Royce Condor engines of 600 h.p. each, but these were not available when the boat was nearing completion. The five Eagles were therefore substituted, and were installed as two tractor and three pusher units. The outboard pusher engines drove four-bladed airscrews, since they had to work in the slipstream of the tractor airscrews. With these engines the Fury was rather underpowered, but still had a remarkably good performance.
  The triplane wings spanned 123 feet. Balanced ailerons were fitted to the top and middle wings, which were of equal span and one bay longer than the bottom wings. The middle wing carried the engines and had a long cut-out in its trailing edge to accommodate the three pusher airscrews.
  One of the most interesting features of the Fury was the advanced thinking displayed in the design of its control system. All control surfaces were fitted with servo-motors, for it was thought that in certain conditions their operation might be beyond the physical capability of the pilot. Moreover, the upper and lower elevators did not move synchronously: the lower elevator was, in effect, a trimming surface, and was operated separately by means of a long lever on a quadrant actuated by the main elevator control rod. On test, the Fury proved to be remarkably light on the controls - lighter, in fact, than the smaller F-boats - and the servo-motors were removed, for their use did not warrant the additional weight.
  The tail-unit underwent modification. As originally built, the Fury had a large central fin of unusual appearance: both leading and trailing edges of this surface sloped upwards and rearwards; and at its upper extremity, wholly above the tailplane, there was a small balanced rudder. Two outboard rudders were also fitted between the tailplanes. Later, the vertical tail was revised to consist of three fins and rudders mounted wholly between the tailplanes. The Fury was designed to fly at an all-up weight of 24,000 lb, but in practice it was found that at 28,000 lb launching, seaworthiness and take-off characteristics were still superior to those of the earlier F-boats. Loading tests were continued to greater weights, and Colonel Porte took off in the Fury in Harwich harbour at a weight of 33,000 lb.
  During its tests the machine was flown by several experienced flying boat pilots, including Majors Arthur Cooper, T. D. Hallam, B. D. Hobbs and Wright, in addition to Colonel (as he later was) Porte himself. Major Hallam has recorded that he flew the Fury with a load of twenty-four passengers, fuel for seven hours and 5,000 lb of sand ballast.
  Some time after the Fury had been completed, in September, 1918, a model of the hull was sent to the National Physical Laboratory for testing in the Froude tank. These tests indicated that certain improvements could be made in the hull and would improve its water performance. Some of the suggested modifications were embodied in the hull. In the course of experiments conducted to investigate the effect of steps on running characteristics the machine had successively one, two and three steps, but finally reverted to two.
  The Felixstowe Fury saw no active service, but continued to be flown occasionally for experimental purposes after the Armistice. At one time there was a plan to fly it across the Atlantic. This flight, whether made from east to west or from west to east, would have been well within the Fury’s capacity, for it had tankage for the enormous quantity of 1,500 gallons of fuel. The Atlantic project was abandoned on the score of expense.
  Several months after Colonel Porte and Major Rennie were demobilised the Fury was wrecked. The pilot was Major Ronald Moon. In the absence of Porte and Rennie no technical officer was in charge of flying, and it seems possible that the boat’s load was not distributed with any consideration for the position of the centre of gravity. Major Moon apparently attempted to take off before the machine had reached its minimum safe flying speed and, in the absence of any reserve of power, the boat stalled. The bottom caved in at the impact.
  In August, 1919, Wing Commander Porte joined the Gosport Aviation Co., Ltd., and designed a series of flying boats for that firm The largest of these was the Gosport G.9, a triplane powered by three 600 h.p. Rolls-Royce Condors and intended for the transport of mails and freight; there were to be seats for ten passengers. The machine was obviously the Fury design modified for commercial use, but Porte succumbed to his disability in October, 1919, and the G.9 was never built.


SPECIFICATION
  Manufacturers: Seaplane Experimental Station, Felixstowe.
  Power: Five 334 h.p. Rolls-Royce Eagle VII; five 345 h.p. (low-compression) Rolls-Royce Eagle VIII.
  Dimensions: Span: 123 ft. Length: 63 ft 2 in. Height: 27 ft 6 in. Maximum beam: 12 ft 6in. Chord: 10 ft. Gap: 8 ft 6 in. Stagger: nil. Dihedral: upper and middle wings 2°, bottom wings nil.
  Areas: Wings: 3,108 sq ft. Tailplane and elevators: 378 sq ft. Fins: 86 sq ft. Rudders: 58 sq ft.

Weights (lb) and Performance:
Flight condition Light load Medium load
No. of Trial Report N.M.250
Date of Trial Report June, 1919
Types of airscrew used on trial 8680, 8701 and 8691
Weight empty 18,563 18,563
Military load 300 300
Crew 720 1,260
Fuel and oil 2,300 5,130
Weight loaded 21,883 25,253
Maximum speed (m.p.h.) at
2,000 ft 97-5 97
6,500 ft 94-5 93
10,000 ft 91 89-5
m. s. m. s.
Climb to
2,000 ft 2 50 3 40
6,500 ft 10 00 14 00
10,000 ft 19 05 28 20
Service ceiling (feet) 14,800 12,000

  Tankage: Petrol 1,500 gallons. Oil 100 gallons.
  Armament: There was provision for four machine-guns and a substantial load of bombs.

Flanders B.2

  L. HOWARD FLANDERS was one of Britain’s pioneer aircraft constructors. In November, 1909, . he joined J. V. Neale as manager, and gained valuable practical experience with the early Neale aircraft. In 1911 he designed and built a handsome monoplane powered by a 60 h.p. Green engine; this machine was quite successful. In 1912 the War Office ordered four Flanders monoplanes of an improved type, powered by the 70 h.p. Renault engine. These machines were complete and about to be handed over to the R.F.C. when the infamous “monoplane ban” came into force.
  The British Military Trials were held on Salisbury Plain in 1912, and one of the entrants was a biplane of Flanders design. Unfortunately, the biplane did not receive its engine, a 100 h.p. A.B.C., in time to enable it to compete in the flying tests. It was later fitted with a 40 h.p. A.B.C. engine, and flew well despite the small amount of power available. The designed speed of the Flanders biplane with the 100 h.p. engine was 83 m.p.h., and it caused a minor sensation by flying at 55 m.p.h. with three people on board when fitted with the 40 h.p. engine.
  In the autumn of 1913 the aircraft was fitted with the 60 h.p. Isaacson seven-cylinder radial engine, which proved to be a very satisfactory power unit. In this form the Flanders B.2 flew frequently and well in the hands of A. Dukinfield-Jones.
  The Flanders biplane had several unusual structural features. As the illustration shows, the fuselage was remarkably deep. It had a single central longeron forming a kind of keel along its underside; behind the cockpits the fuselage tapered to a triangular cross-section at the tail. All the longerons in the nose were of hickory, and in the rear portion of the fuselage they were of ash. The passenger occupied the front cockpit, from which he had a good view in forward and downward directions.
  The central skid of the undercarriage was made of hickory, and was spliced to the keel of the fuselage. Each wheel was on a separate half-axle hinged at its inner end to the central skid. Independent springing was provided by means of twin coil springs in compression on each leg of the undercarriage.
  The wings were of unequal span and chord, and were characterised by the absence of any conventional centre-section bracing. The spars of the wing panels were spruce, whilst those of the centre-section were of ash. Lateral control was by wing-warping.
  The tailplane was a semi-circular surface, and the rudder was strikingly similar to that of the Avro 504.
  By June, 1914, the Flanders B.2 had been fitted with yet another engine. The new power unit was a 70 h.p. Gnome rotary which had been modified to have the valves of an 80 h.p. Gnome.
  On the outbreak of war the machine was bought by the Admiralty and was allocated to the R.N.A.S. station at Great Yarmouth. The delivery flight was punctuated by a series of forced landings, after one of which the machine was dismantled with more vigour than care, and was delivered at Yarmouth in pieces.
  It was intended to scrap the Flanders, but Lieutenant R. J. Bone ordered the machine to be rebuilt. New spars were fitted to the wings and new fabric was applied, and the aircraft was rigged by reference to a photograph which showed it in its original state. Lieutenant Bone tested the Flanders, but it proved to be tail-heavy. A new and larger tailplane was therefore designed and made in the station workshop, and with it the machine was passed as fit for use. There is no record that the Flanders biplane was ever flown in any operational capacity, however.


SPECIFICATION
  Manufacturer: L. Howard Flanders, Brooklands, Byfleet.
  Power: 40 h.p. A.B.C.; 60 h.p. Isaacson; 70 h.p. Gnome.
  Dimensions: Span: upper 41 ft, lower 29 ft. Length: 31 ft 10 in. Chord: upper 6 ft 7 in., lower 5 ft 1 in. Dihedral: nil. Span of tail: 8 ft 6 in. Wheel track: 8 ft. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: upper 270 sq ft, lower 125 sq ft, total 395 sq ft. Tailplane: 28 sq ft. Elevators: 14 sq ft. Rudder: 10 sq ft.
  Weights: 40 h.p. A.B.C. - Empty: 670 lb. Loaded: 1,110 lb. Isaacson - Empty: 1,000 lb. Loaded: 1,571 lb.
  Performance: 40 h.p. A.B.C. - Maximum speed: 56 m.p.h. Initial rate of climb: 200 feet per minute. Isaacson - Maximum speed: 65 m.p.h. Endurance: 4 1/2 hours.
  Tankage: Main (pressure) tank: 15 gallons; service (gravity) tank: 7 gallons; total: 22 gallons.
  Service Use: Flown at R.N.A.S. Station, Great Yarmouth.
  Serial Number: 918.

Grahame-White Type XV

  THE Grahame-White Type XV was a development of the original Grahame-White Box-kite of 1912, and the designation Type XV seems in fact to have been applied to the Box-kite and its two derivatives. There are grounds for believing that one of the earlier forms of the aircraft may have been known as the Grahame-White Type XII, but the type number XV gained general application to all versions.
  The original machine was typical of the box-kite form of aeroplane, and resembled the Farman biplane of 1909 which set a popular and widely-imitated style in aircraft design. Whereas the Farman and most other contemporary box-kite aeroplanes had only single-surface covering on the mainplanes, the Grahame-White biplane had double-surface covering. The Grahame-White machine of 1912 had equal-span wings with four pairs of interplane struts on each side of the aircraft centre line. Ailerons were fitted to upper and lower wings, but were not laterally connected by balance cables. There were both forward and rear elevators. The tailplane was set high and, like the mainplanes, was square-cut. Two rudders were fitted, and earned the machine the nickname of “The Bi-rudder Bus”. The engine was the inevitable 50 h.p. Gnome, and the two occupants sat in complete exposure on a remarkably sketchy framework attached to the lower wing.
  On November 27th, 1913, a Grahame-White Box-kite was the vehicle for an experiment which gave a foretaste of the fighting potentialities of aircraft. On that date, a Lewis machine-gun was fired from a Box-kite piloted by Marcus D. Manton; the gunner was Lieutenant Stellingwerf of the Belgian Army, who sat in a small seat mounted below and behind the pilot’s position. The air-firing tests were made at Bisley, and despite bumpy air Stellingwerf hit a ground target with 11 shots out of 25 on his first attempt, and with 15 out of 47 on his second.
  The first form of the Grahame-White Box-kite saw service in some numbers, both at the Grahame-White flying school at Hendon before the war and with the R.N.A.S. after the outbreak of hostilities.
  In 1914 and 1915 a slightly improved version of the design appeared. The basic airframe remained unchanged, but substantial, slightly tapered extensions were added to the upper wings, and balance cables connected the ailerons. A 60 h.p. Green engine was fitted, and much smaller tail-skids were used; these smaller skids were subsequently fitted to the original equal-span Box-kites. The extended Box-kite was used at the Grahame-White flying school early in the war. Among the distinguished aviators who learned to fly on the early Grahame-White Box-kite was Andre de Meulemeester, the celebrated Belgian fighter pilot.
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Grahame-White Type XIII

  CLAUDE GRAHAME-WHITE, that great pioneer of British aviation, produced his first aeroplane in 1910. That was the Grahame-White Baby, and several other types of widely different forms appeared in the succeeding years.
  For the Circuit of Britain seaplane race of 1914, J. D. North designed a handsome single-engined biplane with very short twin floats; the machine was powered by an English-built 100 h.p. Gnome Monosoupape rotary engine, and bore the Grahame-White type number XIII.
  The outbreak of war led to the cancellation of the race. When the Grahame-White Type XIII was first tested, its short floats were its undoing: when the throttle was opened the seaplane nosed over. The machine was retrieved from the water, repaired, and was thereafter modified to have a wheel undercarriage. The Grahame-White company looked upon the modified machine as a potential two-seat scout, but it was not adopted for Service use. It seems probable, however, that it was used for training purposes at Hendon.
  The single-bay wings were of equal span and had “N” interplane struts; ailerons were fitted to the upper wing only. One of the least desirable features of the Grahame-White Type XIII was the use of auxiliary flying wires which ran from the extremities of the undercarriage axle to both spars of the lower mainplane. The rear portion of the fuselage resembled that of the Morane-Saulnier Type G monoplane, which the Grahame-White company built under licence as their Type XIV; and there was no fixed tailplane. The rudder had a balance area below the fuselage. Transparent panels were let into the fuselage sides, and the roots of the lower mainplanes were also covered with transparent material to improve the pilot’s downward view.
  The pilot occupied the rear cockpit, and the distance between him and his observer was too great to enable the machine to function satisfactorily as a reconnaissance type.


SPECIFICATION
  Manufacturers: The Grahame-White Aviation Co., Ltd., Hendon.
  Power: 100 h.p. Gnome Monosoupape.
  Dimensions: Span: 27 ft 10 in. Length: 26 ft 6 in. Chord: 5 ft 6 in. Gap: 5 ft 6 in. at wing-tips. Dihedral: upper, nil; lower, 2. Incidence: upper 50, lower 30. Span of tail: 8 ft 9 in.
  Areas: Wings: 290 sq ft.
  Weights: Empty: 1,040 lb. Loaded: 1,800 lb.
  Performance: Maximum speed: 85 m.p.h. Endurance: 5 1/2 hours.
  Tankage: Petrol: 50 gallons. Oil: 9 1/2 gallons.
  Service Use: Flown at R.N.A.S. Station, Hendon.

Grahame-White Type XV

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  The ultimate form of the design, which appeared in 1916, looked much less primitive, thanks to the provision of a nacelle for the crew, and was the first version to have full dual control. The forward elevator was removed, but the wings retained the extensions. Power was provided by an 80 h.p. Gnome or Le Rhone engine. Most machines had the short tail-skids and balance cables for the ailerons, but No. 1600 (which provided the type with its Admiralty designation, viz., Grahame-White Biplane Type 1600) had long tail-skids and was without balance cables. It seems quite probable that some at least of the machines which appeared in this final form were produced by rebuilding early versions of the Box-kite design.
  The Grahame-White Box-kite in its several forms gave good but undistinguished service as an elementary trainer with both the R.F.C. and R.N.A.S. It was, in fact, regarded by the Admiralty as a standard type. A few went to Australia, where they were used at the Australian Central Flying School at Point Cook. At least three survived the Armistice and went on to the British Civil Register as K. 111 (later G-EABB), K.112 (G-EABG), and K.113 (G-EABD). Presumably they were intended for use at the Grahame-White flying school, but the registrations of the first two were cancelled in May, 1920, and G-EABD was cancelled on January 10th, 1923, probably long after it was last used.


SPECIFICATION
  Manufacturers: The Grahame-White Aviation Co., Ltd., Hendon, London. Power: 50 h.p. Gnome; 60 h.p. Green; 80 h.p. Gnome; 80 h.p. Le Rhone.
  Service Use: Grahame-White School of Flying, Hendon; R.N.A.S. stations at Chingford, Eastbourne and Eastchurch; No. 31 Training Squadron, R.F.C., Wyton; No. 65 Squadron R.F.C. (training only); Australian Central Flying School, Point Cook, Werribee, Victoria.
  Production and Allocation: A total of 135 Grahame-White Type XV biplanes were built for the R.F.C. and R.N.A.S. The batch A.1661-A.1710 were delivered to the R.F.C., twenty-three in 1916 and twenty-seven in 1917. The others were delivered to the R.N.A.S.
  Serial Numbers: 1600; 3151-3162, built under Contract No. C.P.69521/15; 3607-3616, built under Contract No. C.P.101607/16; 8305-8316; 8752-8801; A.1661-A.1710.
  Notes on Individual Machines: 3152 and 3610 were used at the R.N.A.S. Station, Chingford; 8752 and 8753 were used at the Australian C.F.S., Point Cook; A. 1685 was used by No. 31 Training Squadron, R.F.C.

Grahame-White E.IV, the Ganymede

  THE design of the Ganymede was completed in 1918. The machine was intended to be a long-range day bomber, and in general layout it resembled the three-engined Caproni biplanes and triplanes.
  The central nacelle had a pusher engine installed behind the wings, while each of the two fuselages had a tractor engine at its forward end.
  The Ganymede was designed for three 400 h.p. Liberty engines, but the manufacturers had to be content with three 270 h.p. Sunbeam Maoris. The large spinners and good aerodynamic entry of the tractor engines were marred by the large exhaust manifolds and stacks, and by the large flat radiators. There was a gunner in the extreme nose of the central nacelle, and each fuselage contained a gunner. Not only did each side gunner have a Scarff ring-mounting on top of his fuselage behind the wings, but an opening in the bottom of each fuselage enabled the gunners to repel attacks from behind and below.
  Balanced ailerons were fitted on both upper and lower wings, and the elevators of the biplane tail unit also had horn balances. There were three fins and three rudders.
  The use of engines of less than the designed power inevitably reduced the Ganymede’s performance. The signing of the Armistice prevented development of the design, but the aircraft survived for a time as G-EAMW on the Civil Register.


SPECIFICATION
  Manufacturers: The Grahame-White Aviation Go., Ltd., Hendon, London.
  Power: Three 270 h.p. Sunbeam Maori.
  Dimensions: Span: 89 ft 3 in. Length: 49 ft 9 in. Height: 16 ft. Chord: 10 ft 3 in. Gap: 9 ft 3 in. Stagger: nil. Span of tail: 29 ft. Airscrew diameter: 3-14 metres (approximately 10 ft 3 1/2 in.).
  Areas: Wings: 1,660 sq ft. Ailerons: each 50 sq ft, total 200 sq ft. Tailplanes: 254 sq ft. Elevators: 114 sq ft. Fins: 30 sq ft. Rudders: 50 sq ft.
  Weights: Empty: 11,500 lb. Loaded: 16,000 lb.
  Performance: Maximum speed at ground level: 105 m.p.h.; at 10,000 ft: 93 m.p.h. Estimated speed with Liberty engines: 120 m.p.h. at ground level. Endurance: 9 hours at 10,000 ft.
  Tankage: Petrol: 400 gallons.
  Armament: Three free Lewis machine-guns: one on Scarff ring-mounting at nose of nacelle; one on Scarff ring on cockpit in each fuselage; lower rear tunnel position in each fuselage.
  Serial Numbers: C.3481-C.3483, ordered under Contract No. A.S.38051.

Handley Page Type G

  MR (later Sir) Frederick Handley Page entered the aircraft industry in 1908, when he founded the organisation which, on June 17th, 1909, was incorporated as a limited liability company under the title of Handley Page, Ltd. In its early years, the company built several aeroplanes to the designs of others: among these were a Weiss monoplane, the Planes Ltd. biplane, and the Deverall Saul quadruplane.
  The Weiss monoplane had a considerable influence upon the earliest aeroplanes designed by Handley Page, Ltd., for all the monoplanes had wings with curved, swept-back leading edges, similar to those of the Weiss machine. This configuration was adopted solely to achieve longitudinal stability, for Jose Weiss had earlier demonstrated its effectiveness. Tried experimentally on gliders, the swept-back wing was used on the Handley Page Types A, C, D, E and F.
  All were monoplanes, but in 1913 there emerged from the new Handley Page works at 110 Cricklewood Lane a biplane, known as the Handley Page Type G. Its design embodied all the valuable experience gained with its monoplane predecessors, and it inherited their curved, swept-back wing plan-form. Ailerons, fitted to the upper wing only, replaced the wing-warping of the monoplanes; these ailerons had pronounced wash-out of incidence. Power was provided by an Anzani ten-cylinder radial engine of 100 h.p.
  The structure of the aeroplane underwent several modifications from time to time. In its original form the Type G had a twin-skid undercarriage, and both occupants sat in tandem in the long undivided cockpit. The rounded top-decking of the fuselage tapered down to the fin, and there was a bath-like fairing on the underside of the fuselage beneath the cockpits. There were three bays of interplane struts, the outermost consisting of a slender vee arrangement. It was not long before an additional short strut was added to the outermost struts, bracing the leading edge of the lower wing to a point about a quarter of the way up the rear interplane strut; and later the long forward strut of the vee was replaced by a shorter strut which braced the leading edge of the upper wing to the interplane strut.
  The rudder and elevators had well-rounded trailing edges, and the fin and tailplanes were of triangular shape; the leading edge of the fin was slightly concave. Early in its career, the Handley Page Type G gave a striking demonstration of its stability by flying with its fin and tailplane removed.
  The test-flying of the machine was done by E. R. Whitehouse, who put it through the official tests at Farnborough on December nth, 1913: during these tests it flew successfully with two passengers. In May, 1914, the Type G was flown by W. Rowland Ding for the first time, within a week or two of taking his R.Ae.C. aviator’s certificate. On one of his early flights, Ding damaged the undercarriage on landing, and the opportunity was taken to fit a neater undercarriage consisting of two plain wooden vees. By this time a short piece of top decking separated the two seats.
  The Handley Page biplane was bought by a syndicate headed by Ding. He flew the machine regularly at flying meetings, and in a tour of the provinces made in the summer of 1914 he covered more than 10,000 miles and carried 200 passengers in the Type G.
  Soon after the outbreak of war the machine was bought by the Admiralty, and was based at Hendon for training and Home Defence duties. By this time the appearance of the Type G had again undergone a change: the belly fairing was extended farther aft, a smaller fin was fitted, and fabric-covered wheels replaced the original uncovered wheels. Early in 1915 it was transferred to Chingford, and was flown there by Warren Merriam.
  Its career was nearly brought to an untimely end because of its swept-back wings. At that time, that particular design feature was a characteristic of several enemy types, and while the Type G was flying over London it was riddled by the fire of over-zealous ground gunners who had mistaken it for a German biplane. Fortunately no severe structural damage was caused, and neither occupant was wounded.
  The machine was not particularly good as a trainer, for its inherent stability made it too easy to fly. It survived until August, 1915, when it was badly damaged in a ground accident at Chingford. It was then written off.


SPECIFICATION
  Manufacturers: Handley Page, Ltd., no Cricklewood Lane, London, N.W.
  Power: 100 h.p. Anzani.
  Dimensions: Span: upper 44 ft, lower 32 ft. Length: 25 ft 1 in. Chord: Maximum 6 ft 6 in. Dihedral: 2° on centre line of both rear spars. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: upper 272 sq ft, lower 166 sq ft, total 438 sq ft. Ailerons: each 28 sq ft, total 56 sq ft. Tailplane: 32 sq ft. Elevators: 19 sq ft. Fin: 6 sq ft. Rudder: 12-5 sq ft.
  Performance: Maximum speed at ground level: 73 m.p.h.; at 3,000 ft: 70 m.p.h.
  Armament: One Webley revolver, worn by the pilot.
  Service Use: Used at R.N.A.S. Stations at Hendon and Chingford.
  Serial Number: 892.

Handley Page O/100 and O/400

  IN 1913 the Daily Mail offered a prize of £10,000 to be won by the pilot of the first aeroplane to fly across the Atlantic Ocean. One of the three aircraft which were designed and built for the express purpose of attempting the trans-Atlantic flight was the Handley Page L/200, a large single-motor biplane which had a 200 h.p. Salmson engine. This machine’s capabilities were never put to the test, for the war began before it was completed.
  The historical significance of the Handley Page L/200 lies in the fact that it was the first expression of Mr Handley Page’s belief in the advantages inherent in large aeroplanes, particularly when it was essential to carry a heavy load.
  This belief found further expression when, in December, 1914, the Admiralty issued a statement of their requirements for an aeroplane capable of making oversea patrols with a load of bombs. The specification required the aircraft to have two engines, to carry a crew of two and six 112-lb bombs, and to have a maximum speed of at least 72 m.p.h. The Handley Page design which was shown to Commodore Murray F. Sueter, then the Director of the Air Department of the Admiralty, was for a large biplane powered by two 120 h.p. Beardmore engines. The design impressed him, as also did Mr Handley Page’s faith in big aeroplanes. Apparently determined to outdo even the ambitious requirements of the original specification, Commodore Sueter asked Mr Handley Page to provide a “bloody paralyser” of an aeroplane. That specification may have been technically vague, but the interpretation of it was magnificent.
  Assisted by G. R. Volkert, Mr Handley Page revised the design accordingly, and an order was given for the construction of the machine. The re-designed aircraft had a longer nose than the original project; two 150 h.p. Sunbeam engines were to replace the Beardmores, and the wing span was no less than 100 feet.
  Construction began immediately, and the Handley Page factory worked seven days a week to complete the O/100, as the new machine had been designated. It presented many problems, for it was larger than any aeroplane which had been built in this country up to that time. No one had any practical experience of the construction of aircraft of such size, and every spar, strut and fitting was tested to destruction before it was fitted; yet the prototype was flown less than a year after the date of ordering.
  While the O/100 was being built, the Rolls-Royce company were developing the two aero-engines which were to win distinction as the Eagle and Falcon. By August, 1915, the engine which was later to be known as the Eagle had shown itself to be capable of developing 300 h.p. at 2,000 r.p.m., but to ensure reliability in running the engine was rated at 250 h.p. at 1,600 r.p.m. Two of these Rolls-Royce engines were installed in the O/100.
  The engines were mounted in armoured nacelles, each of which contained an armoured fuel tank. The crew had an enclosed cabin, and were protected by bullet-proof glass and armour plate.
  The completed O/100 was transported by road from Cricklewood to Hendon during the night ol December 17th/18th, 1915, and took off for the first time at 1.51 p.m. on the 18th. As the trials of the aircraft progressed, various modifications were made. One of the first was the removal of the cabin enclosure: in the course of a flight from Hendon to Eastchurch the cabin collapsed and was never used again. Most of the armour plate was also removed. The official trials of the O/100 were carried out at Eastchurch, beginning in January, 1916.
  For the structure of the O/100, its designers wisely contented themselves with adhering to the type of construction with which they were familiar; but it had to be carried out on a much larger scale than anything that had gone before. The fuselage was a cross-braced box girder which was built in three parts: the central portion embodied the bomb bay, and to it were attached the nose and tail portions. The longerons of the tail portion were of hollow spruce, but elsewhere solid spruce was used.
  The wings were also built in sections, the upper in five and the lower in four. The box spars and all interplane struts were built up, and large horn-balanced ailerons were fitted to the upper wings only. The long extensions of the upper wing were braced from king-posts immediately above the outermost interplane struts. The great size of the O/100 presented problems of accommodation, and the wings were made to fold to conserve hangar space.
  The tail-unit was a biplane structure, and the vertical surfaces consisted of a single central fin and two outboard rudders: the fin was mounted on top of the fuselage and, on the O/100, had its leading edge in advance of the tailplane. There were four separate horn-balanced elevators. The incidence of the tailplane could be altered on the ground only.
  The original elevators were not satisfactory. The trouble lay in their horn balances, which were experimentally stripped of their fabric in an endeavour to find a remedy; but finally all save only a very small portion of balance area was removed completely. No attempt was made to modify the shape of the horizontal tail surfaces, and the O/100 was left with the overhanging elevators which became a well-known characteristic of the type.
  The engines were mounted midway between the wings and drove tractor airscrews of opposite hand. The nacelles of the O/100 were, of necessity, long, for each accommodated one of the main fuel tanks, and their tail fairings extended well behind the rear interplane struts. The basic structure of each nacelle was of steel tube. Frontal radiators with vertical shutters later replaced the divided, side-mounted radiators which appeared on some of the early O/100s.
  The undercarriage was a substantial but somewhat complicated affair, built almost wholly of faired steel tube. Each wheel had a large shock-absorber, and 800 X 150 mm or 900 X 200 mm tyres were fitted. There were no brakes: reliance was placed upon the massive sprung tail-skid for braking purposes.
  The prototypes had no provision for defensive armament; but production O/100s had a cockpit in the extreme nose of the fuselage, surmounted by a Scarff ring-mounting, and positions were provided behind the wings both above and below the fuselage. The bombs were suspended by their noses inside the fuselage; the bomb-cells were closed by spring-loaded doors which opened under the weight of the falling bomb.
  Forty O/100s were delivered to the R.N.A.S., beginning in September, 1916, with those which went to Manston to equip the training squadron there. This total included the prototypes, which were modified to production standard before delivery. It was originally intended that the O/100 should be produced by Mann, Egerton & Co., Ltd., of Norwich. For the purpose, that firm had a special large building erected urgently in the space of only six weeks early in 1916. Owing to a change in official plans, however, the planned production did not take place, and Mann, Egerton & Co. built Short Bombers instead of O/100s.
  The first operational unit to receive the big Handley Page was the R.N.A.S. 5th Wing at Dunkerque, which received its first O/100 in November, 1916. It was flown to France by Squadron Commander John Babington, with Lieutenant Jones and Sub-Lieutenant Paul Bewsher as crew; and it was followed two weeks later by a second machine flown by Sub-Lieutenant Waller.
  After a false start on Christmas Eve, 1916, the third Dunkerque-bound O/100 set course for France just before noon on January 1st, 1917. Its crew were Lieutenant Vereker (pilot), Lieutenant Hibbard (observer), Leading Mechanics Kennedy and Wright, and Air Mechanic First Class W. W. Higby. It was followed about a quarter of an hour later by a fourth machine (Sub-Lieutenant Sands, W. Poile, S. Bassett and D. E. Wade). Third time was unlucky for the O/100, for the third machine was delivered intact to the enemy and had no opportunity to demonstrate the warlike qualities implied in the name of “La Amazon” which had been given her by her crew. After flying for some time over and in unbroken cloud, Vereker landed in the first suitable field he saw after breaking cloud at 500 feet. By bad luck the field was twelve miles inside enemy territory near Laon, and an example of Britain’s latest aerial weapon was delivered undamaged into the enemy’s hands.
  German reports indicate that the O/100 was investigated with proverbial Teutonic thoroughness, and it is said that it was once flown by Manfred von Richthofen. For propaganda purposes at the time it was alleged that the design of the German Gotha bombers was copied from or at least inspired by the O/100, and unfortunately that fable survived the war and gained considerable credence. The Gotha went into production in the autumn of 1916, and a German official memorandum issued at that time stated that thirty Gotha G.IVs would be ready by February 1st, 1917. The first production Gothas were in fact delivered to German bombing squadrons in that month. Apart from the date’s incompatibility with any copying of the British design, the Gotha was a totally different aeroplane from the Handley Page, and was not even comparable in size.
  The three O/100s which reached France safely were the only Handley Pages to go there until the beginning of April, 1917, when four went to Dunkerque to form the nucleus of No. 7 Squadron, R.N.A.S. At least one machine went to the R.N.A.S. 3rd Wing at Luxeuil. Early Service use of the O/100 recalled the terms of the original Admiralty specification of December, 1914, for No. 7 Naval flew their machines on daylight patrols off the coast. On April 23rd, 1917, three O/100s, each loaded with fourteen 65-lb bombs, attacked five German destroyers off Ostend and left one listing badly after being stopped by several direct hits.
  Three days later, however, an O/100 was brought down in a similar exploit and was lost. The type was thereafter withdrawn from daylight operations and confined to night bombing, a duty which had been pioneered some six weeks earlier by a single O/100 of the R.N.A.S. 3rd Wing which attacked the railway station at Moulin-les-Metz on the night of March 16th/17th, 1917.
  The O/100s were so few in number that for some weeks the night raids were carried out by single machines. Nevertheless, a single O/100 was a potent weapon in its day. Whereas the Short Bombers of the R.N.A.S. 5th Wing could carry only eight 65-lb bombs, each O/100 could take up to sixteen 112-pounders. To transport an equal load of bombs six D.H.4s were required, and their fuel consumption was 120 gallons per too miles as against the 54 gallons per 100 miles of the O/100. Moreover, the crews of the D.H.4s would total twelve men, whereas the O/100 required only a pilot and two observers.
  The Handley Pages of the 5th Wing bestowed their nocturnal attentions upon the enemy destroyer and U-boat bases at Bruges, Ostend and Zeebrugge; while in the south of France the 3rd Wing’s attacks on enemy industrial centres paved the way for the strategic operations of the Independent Force in the following year.
  In the preparations for the British offensive of 1917 in Flanders, the Dunkerque O/100s assisted by bombing enemy railway centres, notably in and around the Thourout-Cortemarck-Lichtervelde railway triangle. By the middle of August, 1917, R.N.A.S. Squadrons Nos. 7 and 7A possessed a total of twenty O/100s. No. 7A had been formed from a nucleus provided by No. 7 during the previous month, and was itself to provide the nucleus for the formation of No. 14 (Naval) Squadron, which was formed on December 9th, 1917. Some of these O/100s dropped 9 1/2 tons of bombs on the Thourout-Cortemarck-Lichtervelde triangle during the night of September 25th/26th, 1917. Thereafter they confined their attentions to the aerodromes from which the Gothas flew to bomb England, and made life unpleasant on the enemy aerodromes of Gontrode and St Denis Westrem.
  By this time, however, four of their number had been withdrawn to Redcar on September 5th, 1917, in an endeavour to counteract the increasing depredations of enemy submarines off the mouth of the Tees. These O/100s made inshore patrols for four weeks, and bombed seven of the eleven submarines they sighted during that period. None of the U-boats was sunk, but the presence of the Handley Pages made an improvement in the area.
  On October 2nd, 1917, the four O/100s were transferred to Manston as the nucleus of a new bomber squadron. This squadron was originally called “A” Squadron, and was formed for the purpose of making strategic raids against industrial centres in southern Germany. Led by Squadron Commander K. S. Savory, Naval “A” Squadron flew to Ochey to join the 41st Wing on October 17th, 1917. The Wing was the beginning of the Independent Force, R.A.F.
  Nine Handley Pages of Naval “A” Squadron opened the 41st Wing’s night-bombing offensive on the night of October 24th/25th, 1917, when they accompanied sixteen F.E.2b’s of No. too Squadron, R.F.C., in an attack on the Burbach works near Saarbrucken. In January, 1918, Naval “A” Squadron was redesignated No. 16 (Naval) Squadron, and remained on night-bombing duties until the Armistice.
  Only one O/100 was used outside the European theatre of war. In June, 1917, this machine flew from England to Mudros on the island of Lemnos in the Aegean Sea, whence the R.N.A.S. launched a bombing offensive against the Turks in July. The 2,000-mile flight was accomplished in a flying time of 55 hours.
  It was a remarkable achievement at that time, and was made by way of Paris, Rome and the Balkans: while crossing the Albanian Alps at 10,000 feet the water in the radiators froze. The crew of the Handley Page were Squadron Commander K. S. Savory, Flight-Lieutenant H. McClelland, Lieutenant P. T. Rawlings, R.N.V.R., Chief Petty Officer 2(E) J. L. Adams, and Leading Mechanic (C) B. Cromack. The O/100 carried a spare engine, two spare airscrews, hammocks, tents, and a full set of spares; the aircraft weighed 6 1/2 tons at take-off.
  The chief reason for taking an O/100 to the Aegean was to provide means for bombing Constantinople, a flight of some 200 miles from Mudros. After two abortive attempts, Squadron Commander Savory reached the objective shortly before midnight on July 9th, 1917, and was over the target area for thirty-five minutes, during which time twelve 112-lb bombs were dropped. After nearly three months spent in short-range bombing and anti-submarine patrol, the Handley Page again took off for Constantinople on September 30th, 1917, with Flight-Lieutenant J. Alcock at the controls; but engine failure brought the big machine down in the Gulf of Xeros and all the crew were taken prisoner.
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SPECIFICATION
  Manufacturers: Handley Page, Ltd., Cricklewood, London.
  Other Contractors: The Birmingham Carriage Co., Birmingham; Clayton & Shuttleworth, Ltd., Lincoln; The Metropolitan Waggon Co., Birmingham; National Aircraft Factory No. 1, Waddon; The Royal Aircraft Factory, Farnborough, Hants.; The Standard Aircraft Corporation, Elizabeth, New Jersey, U.S.A.
  Power: O/100: two 250 h.p. Rolls-Royce Mk. II (266 h.p. Eagle II); two 320 h.p. Sunbeam Cossack; four 200 h.p. Hispano-Suiza (experimental installation).
  Dimensions: Span: upper 100 ft, lower 70 ft. Length: 62 ft 10 1/4 in. Height: 22 ft. Chord: 10 ft. Gap: 11 ft. Stagger: nil. Dihedral: 4°. Incidence: 3°. Span of tailplanes: 16 ft 7 1/2 in. Track of each undercarriage unit: 4 ft 6 in. Airscrew diameter: 11 ft.
  Areas: Wings: 1,648 sq ft. Ailerons: each 86 sq ft, total 172 sq ft. Tailplanes: 111-6 sq ft. Elevators: 63 sq ft. Fin: 14-7 sq ft. Rudders: 46 sq ft.
  Tankage: O/100: petrol - 130-gallon tank in fuselage, one 120-gallon tank in each nacelle; total 370 gallons; oil - two 12-gallon tanks.
  Armament: The O/100 could carry up to sixteen 112-lb bombs.
  Service Use: O/100: R.N.A.S. Squadrons Nos. 7, 7A (later No. 14 Naval and No. 214 R.A.F.) and “A” (later No. 16 Naval and No. 216 R.A.F.). R.N.A.S. 3rd Wing at Luxeuil. Training Squadron at Manston. Aegean: One O/100 flown from R.N.A.S. Station, Mudros.
  Production and Allocation: Forty-six O/100s were built.
  Notes on Individual Machines: 3116: the first O/100 to land at Coudekerque. 3117: experimental installation of four 200 h.p. Hispano-Suiza engines. 3135: R.N.A.S. 5th Wing, Coudekerque, markings “B 3” on fuselage. 3138: O/100 modified to become O/400 prototype. 
Serial Numbers:
Serial Numbers Contractor Contract No. Specified Engines
Handley Page O/100 :
1455-1466 Handley Page C.P.65799/15 Eagle
3115-3142 Handley Page C.P.69522 Eagle
B.9446-B.9451 Handley Page A.S.20629 Cossack

  Costs:
   Airframe without engines, instruments or armament £6,000 0s.
   Rolls-Royce Eagle Mks. II and IV (each) £1,430 0s.
   Rolls-Royce Eagle VIII (each) £1,622 10s.
   Sunbeam Maori (each) £1,391 0s.
   Fiat A. 12bis (each) £1,617 0s.
   Liberty (each) £1,215 0s.

Handley Page O/100 and O/400

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  Development of the basic design went on during 1917, and modifications were made as a result of operational experience. Squadron Commander (later Air Marshal Sir) John Babington, who had flown the first O/100 to France, was closely connected with the work of development.
  The chief modification was the removal of the fuel tanks from the engine nacelles and the installation of a completely new fuel system. Two cylindrical tanks, each of 130 gallons capacity, were mounted athwartships above the bomb cells, and two 14-gallon tanks were installed in the leading edge of the centre-section above the fuselage: the latter tanks contained the gravity fuel supply. Two wind-driven pumps were fitted, one on either side of the fuselage: these pumps performed the double duty of feeding the carburettors direct and of forcing petrol up to the gravity tanks. In front of each pump was a movable shutter which, by regulating the airstream over the pump’s small airscrew, provided a measure of control over the speed of the pump. The gravity tanks fed the carburettors when the pumps were inoperative, and a hand pump was provided for starting. The oil tanks were mounted in the nacelles behind the engines.
  The engines could be started by compressed air: the supply was contained in bottles in the fuselage. Manual starting was effected by a crank handle, and specially reinforced portions of the lower wings provided platforms for the mechanics who had to perform this duty.
  The first Handley Page to have the new fuel system was No. 3138, which was tested in its modified form in September, 1917; production machines were given the new designation O/400. The removal of the petrol tanks from the nacelles enabled the latter to be shortened to such an extent that it was possible to fit an ordinary interplane strut between the rear spars of the wings at that point. The shape of the upper rear gun position varied somewhat, and the central fin was moved back until its leading edge was slightly behind that of the tailplanes.
  Alternative engines were fitted, probably because of the shortage of Rolls-Royce engines. Even before the prototype O/400 flew, a contract (No. A.S.20629) was placed on July 29th, 1917, for six Handley Pages to be fitted with two Sunbeam engines. The Sunbeam Arab was quoted in at least one official document as the engine in question, but it seems unlikely that the use of two engines of only 200 h.p. each would be worthwhile; and in point of fact B.9446, the first aircraft of this batch of six, had two 320 h.p. Sunbeam Cossacks. These six Handley Pages were, strictly speaking, O/100s, for they had the original outboard fuel tanks, long nacelles and bifurcated rear interplane struts in the engine bay.
  The Sunbeam Maori and Fiat A.12bis were fitted to some O/400s, but the Rolls-Royce Eagle in either its Mark IV or Mark VIII form remained the standard power-unit, and the great majority of O/400s had Eagle engines.
  In November 1917, the O/100 No. 3117 was tested with four 200 h.p. Hispano-Suiza engines. The engines were arranged in two tandem pairs, and anticipated the arrangement used on the later Handley Page V/1500. This experimental installation was made at the Royal Aircraft Factory at Farnborough, under the direction of Major P. Bishop (who became Chief Inspector of the A.I.D.,and lost his life in 1931 in the R.101 disaster). It was not an unqualified success, for at that time there existed no data relating to the behaviour of an airscrew working in the slipstream of another. This O/100 provided a good deal of information which proved useful in the design of the engine installation for the V/1500.
  Experiments were not confined to the power plant, however. Several forms of undercarriage were tested, but none proved to be better than the original, despite its complexity. One machine had ailerons with set-back hinges: balancing was thereby achieved without the use of horn balance areas, and the outer ends of the ailerons were flush with the wing-tips. This may have been a test installation of the ailerons for the V/1500.
  It is significant that a French official aircraft recognition book of May, 1918, includes drawings of a modified Handley Page which not only had a simplified undercarriage but a monoplane tail-unit as well. The tailplane is depicted as resting on top of the upper longerons, and there are twin fins and horn-balanced rudders mounted wholly above the tailplane and fairly close together. The undercarriage is shown with only one wheel on either side, and generally resembles the divided undercarriage favoured by Frederick Koolhoven in his B.A.T. designs.
  Ironically, the decision to produce the Handley Page machine in quantity was hastened by the Gotha. In the summer of 1917 the Air Board was not convinced that there was a need for heavy bombers. The military members thought only in terms of day bombing, and argued that the R.F.C. preferred speed to weight-carrying capabilities in their bombers. Despite a favourable report on the Handley Page, made by the Admiralty representative on the Board, the military members maintained the view that night bombing was less accurate than day bombing. So confirmed were they in this opinion that, at the meeting of the Air Board on July 23rd, 1917, they decided to postpone all orders for experimental heavy bombers.
  The decision was short-lived, for it was roundly denounced by the Controller of the Technical Department, and the question was re-opened by Sir William Weir a week later. The Air Board then approved the ordering of 100 Handley Pages for night bombing and gave further orders for experimental heavy bombers: three prototypes were to be built by Handley Page and Vickers. These orders were for the aircraft which materialised as the V/1500 and Vimy respectively. The contract for the 100 machines, which were built as O/400s, was placed on August 14th, 1917.
  Some members of the Air Board still harboured doubts about the usefulness of heavy night bombers, and all were considerably surprised when, on August 10th, 1917, Captain V. Vyvyan, R.N., placed before them information, based on the experience of the R.N.A.S. 5th Wing, which showed not only that the Handley Pages suffered fewer casualties than the day-bombing D.H.4s but that, generally speaking, night bombing was more accurate than day bombing.
  The Gothas began to make night-bombing attacks on England on September 2nd, 1917, when two machines of No. 3 Bombing Squadron dropped fourteen bombs on Dover. Other raids of increasing intensity followed, and the Air Board, now forcibly convinced of the effectiveness of night bombers, made haste to order 200 more O/400s. When Sir Douglas Haig’s letter of September 10th, 1917, was laid before the Board, members learned of his request that 25 per cent of any further bombing squadrons sent to France should be equipped as night bombers, and promptly ordered yet another hundred Handley Pages.
  Production O/400s did not begin to appear in numbers until the spring of 1918, and in the meantime our heavy night-bombing attacks had been carried out by a mere handful of O/100s.
  As already related, Naval “A” Squadron flew its O/100s to Ochey on October 17th, 1917, and became the first heavy bomber squadron of what was later the Independent Force of the R.A.F. It was, in fact, the only heavy bomber squadron of the Independent Force until No. 97 Squadron arrived, equipped with O/400s, on August 9th, 1918. No. 215 Squadron transferred from the Expeditionary Force on August 19th, and No. 115 arrived from England on August 31st. During August, 1918, No. too Squadron began to exchange its F.E.2b’s for O/400s.
  Two Handley Pages of No. 215 Squadron, flown by Captain W. B. Lawson and Lieutenant M. C. Purvis, made a profound impression on the Germans when they attacked the Badische chemical works at Mannheim on the night of 25th/26th August, 1918. The first machine glided down from 5,000 feet to 200 feet to deliver its attack in the teeth of searchlights and gunfire, and the second O/400 came in at 500 feet. The enemy regarded the attack as most daring, and the munition workers were demoralised not only by the sight of the apparently indestructible Handley Pages flying at such a low height, but also by the fire from the aircraft’s machine-guns which added to the havoc of their bombs.
  It was only in the last three months of the war that the O/400s were used in appreciable numbers; in fact, up to the end of August, 1918, the greatest number of Handley Pages to take off on one night was ten. These machines belonged to No. 216 Squadron, and on the night of August 15th/16th they were bent on attacking Mannheim, Saarbrucken, and the aerodromes at Buhl and Boulay. Only eight of the ten bombed their targets, however, for one machine returned owing to bad visibility and another because of engine trouble. With the advent of the additional squadrons the night-bombing force increased in size: it reached its maximum on the night of September 14th/15th, 1918, when Squadrons Nos. 97, too, 215 and 216 sent off a total of forty Handley Pages to bomb Metz-Sablon, Ehrang, Courcelles, Kaiserslautern, Saarbrucken and Frescaty aerodrome. Nine of the forty were obliged to return with engine trouble, one made a forced landing in our lines, and three failed to return.
  Losses of the Independent Force’s Handley Pages were not light: between June and November, 1918, eighteen were reported missing and fifty-one were wrecked.
  It was during September, 1918, that the O/400s began to deliver the “block-busters” of World War I. These were bombs of 1,650 lb, three of which were dropped on Kaiserslautern by O/400s on the night of October 21st/22nd, 1918. Two nights later, the destruction caused in Wiesbaden by one 1,650-pounder led the inhabitants to think that a group of bombs chained together had been dropped.
  Earlier in 1918, when the tide of war was flowing against the Allies, the Handley Pages of Naval Squadrons Nos. 7 and 14 were diverted to the task of attacking enemy communications. On the night of March 26th/27th, 1918, five machines from each squadron set out to bomb Valenciennes. Seven reached the objective, and their four 250-lb and seventy-six 112-lb bombs did much damage to the crowded railway junction.
  In the early hours of May 10th, 1918, seven Handley Pages of No. 214 Squadron cooperated with Naval forces in the attempt to block Ostend harbour. The bombers dropped six 550-lb, fifty-three 112-lb, and twenty-six 25-lb bombs on the German batteries. The same squadron was requested on May 16th to bomb Bruges on every possible occasion, but by the end of the month No. 214 had only six serviceable Handley Pages and the target suffered less than it ought to have done.
  Also as part of the plan of cooperation with Naval forces, the locks at Zeebrugge were attacked at 2.25 a.m. on May 28th, 1918, by a Handley Page of No. 214 Squadron, piloted by Captain C. H. Darley. After gliding in over Zeebrugge from the sea with his engines silent, Darley dropped his three 520-lb bombs on the locks.
  In Palestine, a single O/400, C.9681, was attached to No. 1 Squadron, Australian Flying Corps. It was flown out from England by Brigadier-General A. E. Borton and Major A. S. C. Maclaren in July, 1918, and did much useful work as a bomber and as a transport carrying supplies for fighting aircraft which were cooperating with Colonel T. E. Lawrence. This O/400 was instrumental in wrecking the enemy’s communications on the eve of Allenby’s offensive: on September 19th, 1918, Captain Ross Smith dropped sixteen 112-lb bombs on the Turkish central telephone exchange at El Affule. After the Armistice this O/400 flew from Cairo to Calcutta by way of Damascus, Baghdad and Karachi. It was to have bombed Kabul during the Afghan War of 1919, but was wrecked in a cyclone while picketed in the open during its flight to the north.
  Production of the Handley Page O/400 was undertaken in America by the Standard Aircraft Corporation, from whom 1,500 were ordered. These machines were powered by two 350 h.p. Liberty 12-N engines. The first American-built O/400 made its first flight on July 6th, 1918. Only 107 were delivered to the U.S. Air Service, the first in September, 1918, for the remainder were cancelled when the Armistice was signed. A few American-built O/400s reached England before the end of the war, and were assembled at Ford Junction aerodrome in Sussex and at Shaw and Oldham in Lancashire. It is believed that other American-built O/400s were assembled by Waring & Gillow, Ltd. By November 17th, 1918, ten machines had been assembled in Lancashire. The type did not continue in American service, however, for by June 30th, 1919, only four were in commission and twenty more were in store. (See also the footnote to the table of serial numbers.)
  After the war the O/400 in various modified forms pioneered air transportation at home and overseas. For this work its good weight-lifting capabilities were an excellent commendation. The passenger-carrying conversions usually had the fuel tanks removed from the fuselage to the engine nacelles, the position they had occupied on the O/100. Eight O/400s were used by the R.A.F. Communication Wing during the 1919 Peace Conference, and carried passengers and mail between London and Paris. The commercial O/400s (in their O/7 guise) of Handley Page Transport, Ltd., operated a regular service between Cricklewood and Paris later in 1919.


SPECIFICATION
  Manufacturers: Handley Page, Ltd., Cricklewood, London.
  Other Contractors: The Birmingham Carriage Co., Birmingham; Clayton & Shuttleworth, Ltd., Lincoln; The Metropolitan Waggon Co., Birmingham; National Aircraft Factory No. 1, Waddon; The Royal Aircraft Factory, Farnborough, Hants.; The Standard Aircraft Corporation, Elizabeth, New Jersey, U.S.A.
  Power: O/400: Prototype - two 275 h.p. Rolls-Royce Mk. II (322 h.p. Eagle VI). Production - two 250 h.p. Rolls-Royce Mk. IV (284 h.p. Eagle IV); two 360 h.p. Rolls-Royce Eagle VIII; two 275 h.p. Sunbeam Maori; two 260 h.p. Fiat A.12bis; two 350 h.p. Liberty 12-N.
  Dimensions: Span: upper 100 ft, lower 70 ft. Length: 62 ft 10 1/4 in. Height: 22 ft. Chord: 10 ft. Gap: 11 ft. Stagger: nil. Dihedral: 4°. Incidence: 3°. Span of tailplanes: 16 ft 7 1/2 in. Track of each undercarriage unit: 4 ft 6 in. Airscrew diameter: 11 ft.
  Areas: Wings: 1,648 sq ft. Ailerons: each 86 sq ft, total 172 sq ft. Tailplanes: 111-6 sq ft. Elevators: 63 sq ft. Fin: 14-7 sq ft. Rudders: 46 sq ft.
  Tankage: O/400: petrol - two 130-gallon tanks in fuselage, two 14-gallon gravity tanks in upper centre-section; total 284 gallons; oil - two 15-gallon tanks.
  Armament: The O/400’s load varied, but could consist of up to sixteen 112-lb bombs, eight 250-lb bombs, three 520-lb bombs, three 550-lb bombs, or one 1,650-lb bomb. There were racks for two additional bombs carried externally under the fuselage. The Type H.A.1a Bomb Sight was fitted externally at the extreme front of the fuselage. Either one or twin double-yoked Lewis machineguns on Scarff ring-mounting on nose cockpit; upper rear cockpit contained either one Lewis gun on a rocking-post mounting or, more usually, two Lewis guns, each on an individual bracket at either side of the cockpit. A further Lewis gun was mounted to fire backwards and downwards through a trapdoor in the floor of the fuselage abaft the mainplanes. Experiments were made with installations of two-pounder and six-pounder Davis guns, but proved to be ineffective.

Weights (lb) and Performance:
Aircraft Prototype O/400 Production O/400
Engines Eagle VI Eagle VI Fiat Maori Maori Eagle VIII Liberty Eagle VIII Liberty
Bomb load None Sixteen 112-lb None None 1,500 lb Sixteen 112-lb 3,000 lb
No. of Trial Report M.143 M.143A M.159 M.202 M.202 M.219 -
Date of Trial Report September, 1917 September, 1917 November, 1917 May, 1918 May, 1918 July, 1918 -
Type of airscrew used on trial A.B.664 A.B.664 A.B.7821 A.B.6934 A.B.6934 A.B.694 -
Weight empty 8,480 8,480 - 8,326 8,326 8,502 7,894
Military load 200 1,992 200 100 1,600 1,974 3,300
Crew 720 720 720 540 540 540 610
Fuel and oil 2,830 2,830 - 1,204 1,204 2,344 2,496
Weight loaded 12,230 14,022 9,961 10,170 11,670 13,360 14,300
Maximum speed (m.p.h.) at
ground level - - - - - 97-5 92
4,000 ft - 86-5 - - - - -
5,000 ft 91-5 83-5 - - - - 90
6,500 ft 88-5 79-5 - 87 78 84-5 -
8,000 ft 85 75 - - - - -
10,000 ft 80 - - 82 - 80 85
m. s. m. s. m. s. m. s. m. s. m. s. m. s.
Climb to
1,000 ft 2 10 2 55 - - - - -
2,000 ft 4 35 6 20 - - - - -
4,000 ft 10 30 14 40 - - - - -
5,000 ft - - - - - - 12 00
6,000 ft 18 00 26 35 - - - - -
6,500 ft - 30 30 24 25 19 50 48 00 27 10 -
7,000 ft - 34 55 - - - - 18 00
8,000 ft 28 10 46 05 - - - - -
9,000 ft 34 40 - - - - - -
10,000 ft 42 35 - 53 30 40 00 - - 32 00
Service ceiling (feet) 10,500 7,000 9,000 10,500 5,500 8,500 10,000
Endurance (hours) 8 8 - - - - -

  Service Use: O/400: Western Front - IX Brigade: R.A.F. Squadrons Nos. 58 (82nd Wing), 207 (54th Wing) and 214 (82nd Wing). VIII Brigade (the Independent Force): R.A.F. Squadrons Nos. 97, 100, 115, 215 and 216 (all of 83rd Wing). Palestine - One O/400 attached to No. 1 Squadron, Australian Flying Corps. Training Units - No. 1 School of Navigation and Bomb-dropping, Stonehenge; No. 2 School of Navigation and Bomb-dropping, Andover.
  Production and Allocation: Forty-six O/100s were built. Approximately 700 Handley Page O/400s were ordered from British contractors and 1,500 in America. About 400 British-built and 107 American-built machines were produced. During 1918, seventy-one O/400s were delivered to the Expeditionary Force, 103 to the Independent Force, eighteen to the 5th Group, ninety-six to Training Units and two to the Middle East Brigade. On October 31st, 1918, the R.A.F. had 258 Handley Page O/400s on charge. Of these, forty-two were with the Expeditionary Force, eighty-four were with the Independent Force, two were with the Middle East Brigade, twenty-four were at Training Units, and thirty-one were at Aircraft Acceptance Parks or with contractors; the remainder were at Aeroplane Repair Depots or at various aerodromes in the United Kingdom.
  Notes on Individual Machines: 3138: O/100 modified to become O/400 prototype. C.9681: No. 1 Squadron Australian Flying Corps. D.8326: modified in 1919 for use by R.A.F. Communication Wing and named H.M. Air Liner “Silver Star”.
Serial Numbers:
Serial Numbers Contractor Contract No. Specified Engines
Handley Page O/400:
B.8802-B.8813 Royal Aircraft Factory 35A/88/C.43 Eagle
C.3381-C.3480 Handley Page A.S.22434 Eagle, Maori or Liberty
C.3487-C.3498 Royal Aircraft Factory A.S.1198 Eagle
C.9636-C.9785 Handley Page A.S.27644 Eagle, Maori or Liberty
D.4561-D.4660 Metropolitan Waggon Co. A.S.28198 Eagle or Liberty
D.5401-D.5450 Birmingham Carriage Co. A.S.28201 Eagle
D.8301-D.8350 Handley Page A.S.18201/18 Eagle, Maori or Liberty
D.9681-D.9730 Clayton & Shuttleworth A.S.28197 Eagle
F.301-F.320 Birmingham Carriage Co. 35A/391/C.284 Eagle
F.3748-F.3767 Handley Page 35A/1052/C.887 Eagle, Maori or Liberty
F.5349-F.5448 N.A.F. No. 1* .A.S.4292 Liberty or Eagle
Between and about J.2251 and J.2262 - - Eagle
* The information relating to the batch F.5349-F.5448 is taken from the official list of O/400 contracts and contractors in the Aeronautical Inspection Directorate Aeroplane Data Book of 1918. The contract was dated May 28th, 1918. However, the statistics of production at National Aircraft Factory No. 1 which are given in Volume VI of The War in the Air do not include any O/400s; yet it is known that at least seventy aircraft of this batch were completed. Another source states that F.5349-F.5448 were ordered from an American manufacturer and that the erection of the Handley Pages in England was to be the responsibility of the Alliance Aeroplane Co., Ltd. (It should be noted that the Alliance company and Waring & Gillow, Ltd., were two of the group of companies founded by Lord Waring.) For use as assembly shops, Lilac Mill, Shaw, and Gorse Mill No. 2, Hollinwood, were taken over in view of their comparative proximity to Liverpool, where the aircraft were landed. But for this statement also no support is to be found in 'The War in the Air', statistics given in Volume III, Appendix VII, do not include any twin-engined bombers built overseas. Moreover, it seems unlikely that as many as seventy American-built O/400s reached these shores; it is believed that the few which did arrive were intended for service with American units.
  The truth of this matter will be difficult to establish. A possible explanation might be that the National Aircraft Factory was so slow to get into its stride that the O/400 contract had to be transferred to another manufacturer. If this hypothesis be extended to include the possibility that one or other of the Waring group of companies might have been the manufacturer concerned, it would not have been illogical for that company to be given the additional responsibility of assembling the American-built Handley Pages on arrival in England. Confusion with the batch F.5349-F.5448 might then have arisen. (It is emphasised that the foregoing reasoning is completely hypothetical and unsupported by any facts so far discovered. Indeed, there is a small amount of evidence which suggests that the batch may have been built by Handley Page, Ltd.)

  Costs:
   Airframe without engines, instruments or armament £6,000 0s.
   Rolls-Royce Eagle Mks. II and IV (each) £1,430 0s.
   Rolls-Royce Eagle VIII (each) £1,622 10s.
   Sunbeam Maori (each) £1,391 0s.
   Fiat A. 12bis (each) £1,617 0s.
   Liberty (each) £1,215 0s.

Handley Page R/200

  THE Handley Page R/200 was a two-seat reconnaissance biplane of compact design which was built for the Admiralty in 1917; it was regarded as appropriate to the Admiralty category N.aA. It was. powered by a 200 h.p. Hispano-Suiza engine, and had interchangeable wheel and float undercarriages: it was flown in both forms. The floatplane version was first flown from the Welsh Harp by Gordon Bell,, and both versions were officially tested at the Isle of Grain Test Depot: the landplane R/200 was there in. February, 1918. The R/200 was a neat and orthodox aeroplane, and was one of the smallest British two-seat Service seaplanes of its day. It contrasted oddly in size with the other Handley Page products of the period. The wings could be folded, and incorporated a form of variable camber gear on their trailing edges. The vertical tail surfaces were of a shape which re-appeared only slightly altered in the much later and larger Handley Page Hyderabad, Hinaidi and Clive.
  The main floats of the seaplane version were of the pontoon type with a single step well aft. A two-bladed airscrew was fitted. The undercarriage of the landplane was a simple vee structure, and the engine drove a four-bladed airscrew of smaller diameter.


SPECIFICATION
  Manufacturers: Handley Page, Ltd., Cricklewood, London. Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: 36 ft. Length: floatplane 29 ft 8 in., landplane 25 ft 1 in. Height: floatplane 12 ft, landplane 10 ft 9 1/2 in. Chord: 6 ft. Gap: 6 ft. Stagger: nil. Dihedral: 2°. Incidence: 2° 30'. Span of tail: 13 ft 9 1/2 in. Airscrew diameter: 9 ft. Each float: 16 ft 6 1/4 in. X 2 ft 4 1/2 in. Distance between float centre-lines: 9 ft. Wheel track: 6 ft. Tyres: 750 X 125 mm.
  Areas: Wings: 390 sq ft.

Weights (lb) and Performance:
Version Floatplane Landplane
Date of Trial Report - March nth, 1918
Type of airscrew used on trial - A.B.7282
Weight empty 1,712 1,882
Military load - 302
Crew - 360
Fuel and oil 0 446
Weight loaded 2,834 2,990
Maximum speed (m.p.h.) at
sea level 93 -
6,500 ft - 95
10,000 ft - 89
m. s. m. s.
Climb to
6,500 ft - - 15 20
10,000 ft - - 29 30
Service ceiling (feet) - 12,000

  Armament: One Lewis machine-gun on Scarff ring-mounting on rear cockpit.
  Serial Numbers: N.27-N.32.

Handley Page V/1500

  IT has already been told, in the history of the Handley Page O/400, how the V/1500 was ordered as an experimental bomber after the meeting of the Air Board which was held on July 30th, 1917. A factor which influenced the design was the expectation that hostilities would continue until well into 1919 at least, and the machine had to be capable of taking a worthwhile bomb-load from bases in England to Berlin and other enemy industrial centres.
  The V/1500 was therefore necessarily a large aeroplane, larger, in fact, than any which had been built in Britain up to that time. It was not quite so large as some of the contemporary German Riesenflugzeuge (Giant aeroplanes), but was a much more workmanlike aircraft and a good deal simpler structurally than any of the enemy types.
  The huge airframe embodied all the experience gained in the construction of the O/100 and O/400. The fuselage of the V/1500 was made in three sections. The front section was built mainly of silver spruce, and was covered with plywood for a distance of seven feet from the nose. The centre portion contained the bomb-bay, and was built wholly of spruce apart from two cross beams in the bomb-bay, which were of ash. The upper half of the centre portion was occupied by the main fuel tank; below it the bomb-racks were fitted. The rear portion of the fuselage was constructed of McGruer circular spruce sections, and there was a cat-walk which extended to the gunner’s cockpit in the extreme tail of the aircraft. The whole fuselage was a cross-braced box girder.
  The upper mainplanes were built in five sections, the lower in six; despite their great size the wings could be folded. Silver spruce box spars were used, and the compression struts were either box-type structures or of the McGruer tubular type; the ribs were of silver spruce, and cross-bracing was by tie-rods. The ailerons had solid spars; they and the aileron ribs were made of silver spruce. The upper centresection contained four water tanks and two gravity tanks for petrol; the latter were each divided into two compartments. The interplane struts were built up of wood, whilst the struts supporting the engine-bearers were of steel tube, as were the bearers themselves.
  Late in 1917, the Rolls-Royce company began work on the design of a new engine which was intended to be the power-unit of the V/1500. This was the Condor, which was virtually a considerably enlarged Eagle: the bigger engine had a modified cylinder head design, four valves per cylinder instead of the Eagle’s two, and correspondingly revised valve gear. The first experimental Condors delivered 600 h.p. and would have been ideal for the V/1500. However, they were not ready until early 1919, and it was necessary to instal other engines in the aircraft. Four Rolls-Royce Eagles were fitted, mounted midway between the wings in two tandem pairs. The tractor engine on each side drove a two-bladed airscrew, and the pusher drove a four-blader of smaller diameter. There was one oil feed tank to each pair of engines, situated above the forward power-unit.
  The tail-unit was a biplane structure with four vertical surfaces. The tailplane leading edges and spars were solid spruce, as were the elevator spars; the elevator trailing edges were of steel tube.
  The undercarriage was necessarily substantial yet structurally simple: there were two twin-wheel units, and the front leg of each vee incorporated an oleo shock absorber. Each wheel was 5 feet in diameter. The massive tail-skid was made of solid ash, and was sprung by rubber shock-absorber cord.
  The components of the prototype V/1500 were made in great secrecy by Messrs Harland & Wolff at Belfast. This firm’s first contract for twenty V/1500s was dated January 27th, 1918, and it appears that the aircraft was more or less ordered off the drawing-board, for the prototype did not fly until May, 1918. If this were so, it was a remarkable act of faith on the part of the Air Board.
  The prototype V/1500 had several features which were not perpetuated in production machines. The most obvious of these was the large single radiator, mounted on top of the fuselage in front of the forward centre-section struts: this radiator served all four motors. At this time the engines had no cowlings of any kind.
  The ailerons had triangular inset horn balances. The tailplanes had a rather narrow gap; there were no fixed fins; and all four rudders were balanced surfaces pivoted on the front spars of the tailplanes. Inter-tailplane struts were fitted between the rear spars.
  The first flight of the V/1500 took place in May, 1918, when the prototype was flown by Captain Busby, R.F.C. His crew consisted of F. A. Kappey and Mr Hathaway. The flight was made from Cricklewood, and was followed by several further test flights during the next few weeks.
  Control response was not completely satisfactory, and various modifications were made during the course of these flights. The original horn-balanced ailerons were replaced by surfaces with set-back hinges; and a little later the balance areas of the rudders were reduced by removing an area of fabric from each.
  Directional control was still unsatisfactory, and the fin area was increased by fitting a single rectangular surface above the upper tailplane and by adding a long pointed fairing to the extreme tail of the fuselage. Ultimately, a drastically revised tail-unit was fitted: it had a greatly increased gap to enable enlarged vertical surfaces to be fitted. Inter-tailplane struts were fitted between the front spars of the tailplanes, and immediately behind these struts were four substantial fins; each fin carried a plain unbalanced rudder.
  Modifications to other parts of the machine were also made concurrently. When the ailerons were changed, the large central radiator was replaced by two tall upright radiators, one at the front of each pair of engines; by this time the engines had been enclosed in rather bulky nacelles. The foremost portion of fuselage-decking was removed and the nose gun position was made.
  By the time the final form of tail-unit was fitted, the engine cowlings had been discarded and only their framework remained.
  The prototype V/1500 made its last flight in June, 1918. Captain Busby and Hathaway took four passengers, one of whom (Colonel Ogilvie) occupied the gunner’s cockpit in the extreme tail. On this flight the machine crashed and was completely burnt out. Colonel Ogilvie alone survived because of his remote position.
  Development was delayed until a second machine - almost certainly the first production V/1500 - became available in October, 1918.
  In the production aircraft the engine cowlings were completely discarded. It was found that 500 lb of weight was saved, and performance suffered very little. Hexagonal radiators were fitted in place of the tall rectangular radiators of the prototype. Scarff ring-mountings were fitted to the cockpits in the extreme nose and tail of the fuselage; the latter defensive position was pioneered by the V/1500. There was a third gunner’s position on top of the fuselage just behind the wings.
  The Air Ministry’s first provisional expansion programme for the Independent Force was forwarded to the Admiralty and War Office on June 20th, 1918. This envisaged a total of 340 Service squadrons by the end of September, 1918. Of that total, sixty squadrons were to be with the Independent Force, forty in France and twenty night bomber squadrons based in England. Thus was born a new conception of bombing technique, made possible by the potentialities of the Handley Page V/1500.
  The expansion programme underwent several changes, until by the end of October the English-based squadrons of the Independent Force had been reduced to eight.
  The English-based bombing force was to operate under the command of Major-General Trenchard, and No. 27 Group began to organise early in September, 1918, under Lieutenant-Colonel R. H. Mulock at Bircham Newton, Norfolk. It was to consist of the 86th and 87th Wings, and it was intended that the former should operate from England and that the latter should go to France after formation.
  The first squadron of No. 27 Group to be mobilised was No. 166. The crews for the squadron’s V/1500s were carefully selected, many of them seasoned pilots and observers from the night-bombing F.E.2b squadrons. To them, their aircraft were known as super-Handley Pages or super-Handleys.
  But of the total of 255 super-Handleys which had been ordered, only three were ready for use at the time of the Armistice, and the V/1500’s capabilities remained untested, its ability to carry the war to the enemy’s capital unexploited. Had it gone into large-scale service both in France and in England it would have been a weapon to reckon with, for on shorter raids it could carry no fewer than thirty 250-lb bombs or their equivalent weight. The bomb load for a Norfolk-Berlin raid could hardly have exceeded 1,000 lb, but by late 1918 Britain had a 3,300-lb bomb which was intended for use with the V/1500.
  For the V/1500s ordered from the Beardmore Company, four of the 500 h.p. Galloway Atlantic engines were specified. The Napier Lion.was another alternative power unit for the aircraft, and four Liberty engines were to have been tried.
  After the Armistice the big Handley Page saw little service. The immediate economies of the postwar world favoured the smaller and less complicated Vickers Vimy.
  Before the end of 1918 a V/1500 named H.M.A. Carthusian took off from Martlesham to commence the first through flight from England to India. The flight began on December 13th, 1918, and ended, after many vicissitudes, on December 30th, when the V/1500 landed at Karachi after flying the last 35 miles just above stalling speed with only two engines functioning. The V/1500 was flown by Major A. S. C. Maclaren, M.C., and Captain Robert Halley, D.F.C., accompanied by Brigadier-General N. D. K. McEwen and three mechanics.
  This V/1500 was probably the only aeroplane of its type to drop bombs with lethal intent. The Afghan war had broken out, and it was desired to attack Kabul. It was originally intended that the raid should be made by the Handley Page O/400 which had been attached to No. 1 Squadron of the Australian Flying Corps, for it was thought that the fully loaded V/1500 might not be able to climb high enough to clear the Pathan Hills. When the O/400 was wrecked in a cyclone, however, the V/1500 had to be used, and Captain Halley successfully took it to Kabul, dropped his bombs, and returned safely.
  Another V/1500 was shipped to Newfoundland in 1919 to attempt the trans-Atlantic flight, but was forestalled by Alcock and Brown’s crossing in a Vimy.
  At home, the V/1500 demonstrated its weight-lifting capabilities and its long range on several occasions. On November 15th, 1918, one took its pilot and forty passengers to nearly 6,500 feet over London with enough fuel on board for a six-hour flight. Several notable long-distance flights were made by the V/1500; the pilot on these occasions was Clifford B. Prodger. However, the type was too expensive an aircraft for the nascent air transport industry, and it found no lasting commercial application.
  As an aeroplane, the V/1500 must be recognised as one of the finest achievements of the British aircraft industry during the war, and it initiated a bombing plan which, a quarter of a century later, was translated into action by its lineal descendant, the Halifax.


SPECIFICATION
  Manufacturers: Handley Page, Ltd., Cricklewood, London.
  Other Contractors: William Beardmore & Co., Ltd., Dalmuir, Dunbartonshire; Harland & Wolff, Ltd., Belfast.
  Power: Four 375 h.p. Rolls-Royce Eagle VIII; four 500 h.p. Galloway Atlantic; four 450 h.p. Napier Lion; four 400 h.p. Liberty 12.
  Dimensions: Span: 126ft. Length: 62 ft. Height: 23 ft. Chord: 12 ft. Gap: maximum 15 ft, minimum 12ft. Stagger: nil at centre-section, 2-5 in. at outer struts. Dihedral: upper, nil; lower 40 05'. Incidence: 40. Airscrew diameter: tractor 13 ft 5 in., pusher 10 ft 4 in.
  Areas: Wings: 3,000 ft.

  Weights (lb) and Performance:
No. of Trial Report M.228 M.256
Date of Trial Report September, 1918 May, 1919
Types of airscrew used on trial - A.B.8420, A.B.8501
Weight empty 16,210 17,602
Military load 3,120 80
Crew 1,080 1,080
Fuel and oil 4.290 5.3i8
Weight loaded 24,700 24,080
Maximum speed (m.p.h.) at
6,500 ft - 90-5
8,750 ft 97 -
10,000 ft - 855
m. s. m. s.
Climb to
6,500 ft 18 30 21 05
10,000 ft - - 41 25
Service ceiling (feet) 10,000 11,000
Endurance with quoted fuel load - 6 hours
Maximum endurance - 14 hours

  Tankage: Petrol: 1,000 gallons.
  Armament: One Lewis machine-gun, or double-yoked pair, on Scarff ring-mounting on nose cockpit; one Lewis gun on central socket and pillar mounting, or two Lewis guns on beam socket and pillar mountings in dorsal gunner’s position; one Lewis gun on Scarff ring-mounting on tail cockpit. The bomb load could consist of up to thirty 250-lb bombs.
  Service Use: No. 166 Squadron, R.A.F., Bircham Newton. Production: A total of 255 Handley Page V/1500s were ordered, but only six had been delivered by the end of 1918. On October 31st, 1918, only two were on charge with the R.A.F.; both were at an experimental station.

Serial Numbers:
Serial Nos. Contractor Contract No. Specified Engines
B.9463-B.9465 Handley Page A.S.22690 Eagles
E.4304-E.4323 Harland & Wolff 35A/I85/C.74 Eagles
E.8287-E.8306 Beardmore 35A/315/C.200 Atlantics
F.7134-F.7143 Handley Page 35A/1455/C.1528 -
F.8201-F.8230 Handley Page - -
F.8281-F.8320 Handley Page - -
H.4825-H.4864 Handley Page - -
J.6523-J.6572 Handley Page - -

  Costs:
   Airframe without engines, instruments and guns £12,500 0s.
   Rolls-Royce Eagle VIII engine (each) £1,622 10s.

Kennedy Giant

  IT has been said that Chessborough J. H. Mackenzie-Kennedy was the man who took aviation to Russia. At the age of eighteen he went there with three pounds in cash and a strong belief in the possibilities of aviation. He went to the Putiloff Gun Works and discussed his plans to such good purpose that he almost immediately became a member of the Imperial Russian Technical Society and was given a good deal of support.
  By 1908 he had completed the design of the first Russian aeroplane, and in the following year he formed the Kennedy Aeronautic Company. In 1911 he met Igor Sikorskii, and the two became friends. Both were convinced of the practicability and usefulness of very large aeroplanes, and in 1913 there appeared the first Sikorskii four-engined biplane, with the design of which Kennedy had been associated.
  Soon after the outbreak of war Kennedy returned to Britain. The success of the big Sikorskii machines had fired his enthusiasm afresh, and he forthwith took his own ideas for a giant aeroplane to the War Office. He was rewarded with permission to construct a prototype, and set up his design office at 102 Cromwell Road, South Kensington. Associated with him were T. W. K. Clarke, who had been one of the pioneers of aviation in Britain, E. A. Vessey and G. C. McClaughlin.
  The construction of the Kennedy Giant was undertaken by the Gramophone Company, Ltd., and the Fairey Aviation Company, Ltd., both of Hayes, Middlesex. The completed components were sent to Northolt aerodrome for assembly towards the end of 1916, but the machine was so large that it had to be erected in the open: there was no hangar large enough to accommodate it.
  In appearance the Kennedy Giant bore a general resemblance to the Sikorskii Ilya Mourom’etz. The deep and commodious fuselage provided completely enclosed accommodation for the crew: the pilot sat in the extreme nose, and behind his compartment were a navigation room and other cabins. Windows were fitted along the entire length of the fuselage.
  The completion of the Giant was not accomplished without incident. The surviving accounts contain the elements of conflict and confusion, and doubtless the passing of time has blurred the details. One account says that when the first attempt to move the Giant was made, it needed the combined efforts of two lorries and seventy men to haul it along. These exertions proved too much for the machine, for it broke its back. The fuselage was shortened by about ten feet and repaired, and construction proceeded.
  It has also been recorded that the mainplanes had to be moved aft by an appreciable distance during the erection of the aircraft; assembly was thereby delayed.
  Structurally the Giant was more or less conventional. The fuselage was a cross-braced box girder of almost constant depth, and terminated in a rudder which could hardly have been adequate even if the fuselage had been longer or the mainplanes farther forward. It looked absurdly small on the completed machine, but was later replaced by a very much larger horn-balanced rudder; the original plain elevators were also replaced by horn-balanced surfaces.
  Ailerons were fitted to the upper wings only, and were actuated by long spanwise shafts which ran along the wing just above the leading edge. A similar control system operated the elevators. The undercarriage was a wonderfully complicated affair which had four wheels and a multiplicity of struts.
  Unfortunately for Kennedy, the only engines which the authorities would release for his machine were some British-built Salmson water-cooled radials of 200 h.p. each. The serial numbers of these engines indicate that they were among the first Salmsons to be made by the Dudbridge Iron Works, Ltd., who held the British licence for their manufacture.
  The engines were mounted above the lower wing in two tandem pairs, and each engine had two radiators, one on either side. The intention was that these engines should be cleanly cowled, for large pointed spinners were later fitted to the pusher airscrews. With only 800 h.p. available the Giant was badly underpowered.
  The first attempts to fly the aircraft were made late in 1917 by Lieutenant Frank T. Courtney, who was then an instructor with No. 35 Training Squadron at Northolt. After several attempts had proved unsuccessful, Courtney taxied at full throttle down a slight slope from the hangars against a stiff breeze, but even that rather desperate action resulted in no more than a straight hop with the wheels off the ground but with the tail-skid trailing.
  No further attempts were made to fly the Giant. For want of sufficiently powerful engines it was never properly completed, and lay derelict at Northolt for several years. Kennedy retained his faith in large aeroplanes, for in 1919-20 a second Giant of his design was under construction at the Victoria Works of John Dawson & Company, Ltd., Newcastle-on-Tyne. This was to have been smaller than its predecessor: the span was to have been too feet, the length 55 feet, and the estimated useful load was 6,500 lb. Better luck with engines was obviously hoped for: the estimated maximum speed of the second Giant was 120 m.p.h. Kennedy’s venture failed financially in December, 1920, however, and his new aircraft was never completed.


SPECIFICATION
  Manufacturers: Kennedy Aeroplanes, Ltd., 102 Cromwell Road, South Kensington, London, W.7. Components made by the Gramophone Company Ltd., Hayes, Middlesex, and by the Fairey Aviation Company, Ltd., Hayes.
  Power: Four 200 h.p. Salmson, engines numbered 2, 6, 8 and 10.
  Dimensions: Span: 142 ft. Length: 80 ft. Height: 23 ft 6 in. Chord: 10 ft. Gap: 10 ft.
  Weights: Empty: 19,000 lb.
  Serial Number: 2337.

Lakes Flying Co. (later N.A.C.) Monoplane

  BY the end of 1912 the Lakes Flying Co. found that the Water Hen was no longer able to cope on its own with the growing demands for pleasure flights. The company therefore commissioned O. T. Gnosspelius to design a new floatplane for use on Lake Windermere.
  Mr Gnosspelius had designed a little monoplane with a broad-beamed central float in 1911. With it he had attempted a flight shortly before the Water Hen first flew, but the Gnosspelius machine was overturned by a gust of wind just as it took off. It was later successfully flown on February 13th, 1912.
  Mr Gnosspelius had an original turn of mind, and the new floatplane that he designed for the Lakes Flying Co. was almost unique, for it was a pusher monoplane. The machine was built by Borwick & Sons of Bowness.
  The monoplane wing was mounted at the level of the upper longerons of the boat-shaped nacelle. An 80 h.p. Gnome engine was fitted at the stern of the nacelle. There were four tail-booms: the upper pair were attached to the wing, the lower pair to the undercarriage bracing system. The wings were braced by cables; landing loads were taken by cables running from a double cabane system.
  The original undercarriage consisted of a large central float, with outboard floats for stability. A small tail float was also fitted.
  The monoplane was taken over by the Northern Aircraft Co. in 1914; thereafter it was usually referred to as the N.A.C. hydro-monoplane. Like the Water Hen, it was later given a twin-float undercarriage with two single-step pontoon-type floats. When these were fitted the outboard floats were removed.
  After the outbreak of war, the monoplane shared with the Water Hen the duty of training seaplane pilots for the R.N.A.S., and was used in that capacity until 1916.


SPECIFICATION
  Manufacturers: Built by Berwick & Sons, Bowness-on-Windermere, for the Lakes Flying Co.
  Power: 80 h.p. Gnome.

Lakes Flying Go. (later N.A.G.) Water Hen

  CAPTAIN E. W. WAKEFIELD was one of the little-known pioneers of aviation in England. As early as 1909 he publicly expressed his belief that, in the state of aeronautical knowledge at that time, the best type of aircraft to develop would be one capable of rising from and alighting on water. Such a machine, he argued, would be less susceptible to the type of damage so frequently sustained by contemporary aeroplanes.
  Wakefield’s ideas were scorned, but his faith in the seaplane was soon vindicated by the successful flights made by Henri Fabre’s “hydro-aeroplane” at Monaco and, later, by Glenn Curtiss in America. The Curtiss aircraft was a biplane fitted with a central-float undercarriage.
  Captain Wakefield and a few friends formed the Lakes Flying Co. in 1911 and commissioned A. V. Roe to build a centre-float seaplane generally similar to the Curtiss machine. The aeroplane which was built against this order was known as the Waterbird, and had a single narrow float mounted centrally. Although reasonably efficient, the Waterbird did not come up to expectations: it was flying in November, 1911, and had the distinction of being the first successful British aircraft to be designed as a floatplane from the beginning.
  Meantime, representatives of the Lakes Flying Co. had been studying developments in the design and construction of aeroplanes. They applied their knowledge to the design of a new floatplane, which was completed by the spring of 1912.
  The new aircraft was named Water Hen. It was an unequal-span pusher biplane with both front and rear elevators; the engine was a 50 h.p. Gnome rotary. The first float to be fitted to the Water Hen was 12 feet long and 6 feet in beam, and was made by Borwick & Sons, a firm of boat-builders of Bowness-on-Windermere. It was made of mahogany and canvas, and had three steps. An improved single-step float was later fitted; it had silver spruce frames and three longitudinal bulkheads. The planing bottom was covered with aluminium, the sides with duralumin, and the top with Willesden canvas. The float was connected to its attachment frame by means of rubber cord. Stability on the water was ensured by two small air sacks, one mounted under each lower wing.
  The Water Hen was designed to be a slow-flying aircraft, for it was intended to have a low take-off speed and to be able to lift a passenger easily. The passenger sat high up between the wings, and the pilot’s seat was lower down, immediately in front of the lower wing. There was no protection of any kind for either occupant.
  The aircraft was an instant success, and its basic design was little altered throughout its long career. The fitting of the improved float has been mentioned, and subsequent modifications were of a similar nature.
  The Water Hen was used at Lake Windermere as a joy-riding machine, and flew with a regularity which was outstanding for the time. By the beginning of December, 1912, it had made 250 flights and had carried 100 passengers during the seven months it had been in existence.
  The Water Hen was still flying when war broke out, by which time it had been modified by the addition of a small nacelle to protect the pilot and passenger, whose seats had been suitably re-aligned; and the big central-float had been replaced by two separate pontoon-type floats. When this last modification was made the wing-tip floats were removed.
  The Lakes Flying Co. was succeeded by the Northern Aircraft Co., who continued to operate the Water Hen. A number of R.N.A.S. seaplane pilots received their initial instruction on this veteran seaplane, which continued to fly until 1916 as if in vindication of Captain Wakefield’s belief in the usefulness and safety of floatplanes.


SPECIFICATION
  Manufacturers: The Lakes Flying Co., Cockshott, Windermere (float made by Borwick & Sons, Bowness-on-Windermere).
  Power: 50 h.p. Gnome.
  Dimensions: Span: upper 42 ft, lower 32 ft. Length: 36 ft 5 in. Chord: 5 ft. Gap: 5 ft. Stagger: nil. Span of tail: 6 ft 10 in. Span of forward elevator: 6 ft 10 in. Airscrew diameter: 8 ft 6 in.
  Areas: Wings: 365 sq ft. Tailplane: 11 sq ft. Elevators: rear 6-5 sq ft, front 17-5 sq ft. Rudder: 9-5 sq ft.
  Weights: Empty: 780 lb. Loaded: 1,130 lb.
  Performance: Maximum speed: 45 m.p.h. Ceiling: 800 ft.

London and Provincial School Biplane Type No. 4

  THE London and Provincial Aviation Co. operated a flying school at Hendon aerodrome from 1914 onwards. The company built some training machines of the Caudron type for use at their school.
  In 1916, A. A. Fletcher left the Martinsyde concern to join the London and Provincial company, and he designed two trainer aircraft for his new firm. The first of these was a small and thoroughly conventional little two-bay biplane, powered by a 50 h.p. Gnome rotary engine, and known as the London and Provincial Type No. 4.
  The London and Provincial concern later moved to their own aerodrome at Edgware, and it was there that the machine was flown.
  After the Armistice, the London and Provincial company tried to market the little Gnome-powered biplane as a cheap aeroplane powered by an engine which was easily obtainable. Unfortunately, the Gnome’s lack of dual ignition led to the A.I.D.’s refusal to approve the aircraft, and production could not be undertaken.


SPECIFICATION
  Manufacturers: The London and Provincial Aviation Co., Edgware, London, N.
  Power: 50 h.p. Gnome.
  Dimensions: Span: 32 ft 6 in. Length: 25 ft 3 in. Height: 8 ft gin. Chord: 4 ft 74 in. Gap: 5 ft. Span of tail: 10 ft 6 in. Airscrew diameter: 7 ft.
  Areas: .Wings: 280 sq ft. Ailerons: each 10 sq ft, total 40 sq ft. Tailplane: 24-75 sq ft. Elevators: 16-25 sq ft. Fin: 3 sq ft. Rudder: 6 sq ft.
  Weights: Empty: 655 lb. Loaded: 1,070 lb.
  Performance: Maximum speed at ground level: 60 m.p.h. Climb to 5,000 ft: 20 min. Endurance: 11 1/2 hours.
  Tankage: Petrol: 8 gallons. Oil: 4 gallons.



London and Provincial School Biplane

  DEVELOPED from the Gnome-powered London and Provincial Type No. 4 was the larger two-seater with the 80 h.p. Anzani radial engine: it appeared in the middle of 1916. The later machine displayed several characteristics which combined to produce a certain likeness to Fletcher’s earlier design, the Martinsyde Elephant.
  In construction, the Anzani-powered London and Provincial biplane was typical of its period. The fuselage was basically of rectangular section with ash longerons; the forward portion had diagonal spruce struts for bracing and was covered with ash plywood, and the rear portion was cross-braced by wire in conventional fashion. A rounded top-decking was fitted.
  The equal-span wings were also of wooden construction and had sharply-raked tips: ailerons were fitted to upper and lower mainplanes. The tail surfaces were of generous area and conventional construction. The undercarriage was a simple vee structure consisting of two faired steel tube vees connected by two steel tube spreader-bars between which the axle lay. The wheel track was unusually wide, presumably to ensure ground stability in an aeroplane intended for use as a trainer.
  The type was built in small numbers by the London and Provincial Aviation Co. for use at their own school, and the machine proved to have good flying qualities. It was quite manoeuvrable, and in the hands of G. Smiles set up a number of looping records at Hendon in 1916.
  For experimental purposes, one of the London and Provincial machines was flown with a set of S.E.5 mainplanes strapped to the underside of its own lower wings. Presumably this was done to test the feasibility of transporting spares in this way; it is recorded that the London and Provincial biplane flew satisfactorily with its unusual load.
  Later, the type was used in parachute experiments, and many jumps were made with “Guardian Angel” Parachutes. On July 10th, 1918, W. L. Wade, wearing one of these parachutes, made a live drop from an L. and P. Anzani biplane flying at 400 feet. The aeroplane was flown by Captain R. Payze, R.A.F.
  Five London and Provincial biplanes came on to the British Civil Register after the Armistice. The machine which became G-EAQW was fitted with a 100 h.p. Anzani instead of the original 80 h.p. engine.


SPECIFICATION
  Manufacturers: The London and Provincial Aviation Co., Edgware, London, N.
  Power: 80 h.p. Anzani; 100 h.p. Anzani.
  Dimensions: Span: 37 ft. Length: 25 ft. Chord: 5 ft. Gap: 5 ft. Dihedral: 1° 30'. Span of tail: 12 ft 10 in. Wheel track: 7 ft. Airscrew diameter: 8 ft.
  Areas: Wings: 350 sq ft. Ailerons: each 14 sq ft, total 56 sq ft. Tailplane: 36 sq ft. Elevators: 19 sq ft. Fin: 6 sq ft. Rudder: 9 sq ft.
  Weights (with 80 h.p. Anzani): Loaded: 1,400 lb.
  Performance: Endurance: 3 hours.

Mann, Egerton Type B

  THE well-known motor-car building firm of Mann, Egerton & Co., Ltd., placed their manufacturing resources at the disposal of the Admiralty in the spring of 1915. The response to this offer was an official request that the company should build seaplanes. The first type of aircraft to be produced was the Short Seaplane Type 184, for which Mann, Egerton & Co. were among the earliest contractors. The firm regarded the Short 184 as their own Type A.
  While the Shorts were in production, the company were asked to assist in the design of a seaplane very similar to the Short 184 but intended to be an improved type. The modified aircraft, designated Type B by Mann, Egerton & Co., incorporated a large number of standard Short 184 components, but differed markedly in having wings of unequal span. There were two bays of interplane bracing, but the upper wings had enormous extensions which were liberally braced by cables; there were tall king-posts above the outer interplane struts. Each upper wing was made in two sections which met immediately outboard of the king-posts. The outer sections carried the ailerons, which were inversely tapered. No ailerons were fitted to the lower wings. The wings could be folded, and slinging gear was fitted above the centre-section.
  The fuselage, tail-unit and undercarriage appeared to be standard Short 184 components. The 225 h.p. Sunbeam engine was fitted, but was mounted a few inches higher than in the Short. Consequently the nose lines of the Mann, Egerton Type B were slightly different, and the top decking behind the radiator sloped downwards to the pilot’s cockpit.
  Only ten aircraft of the type were built and were delivered in 1916. They were used by the R.N. A.S. for patrol duties, in company with standard Short 184s.


SPECIFICATION
  Manufacturers: Mann, Egerton & Co., Ltd., Prince of Wales Road, Norwich.
  Power: 225 h.p. Sunbeam.
  Armament: One Lewis machine-gun in observer’s cockpit. Bombs could be carried on racks under the fuselage.
  Service Use: R.N.A.S. Seaplane Station, Calshot.
  Production: Ten Mann, Egerton Type B seaplanes were built.
  Serial Numbers: 9085-9094.

Mann, Egerton H.1 and H.2

  AFTER the Type B seaplane, production of aircraft by Mann, Egerton & Co. continued with the construction of a batch of Short Bombers, designated Type C (with short fuselage) and Type CA (with long fuselage) by the firm. These were followed by the Sopwith 1 1/2-Strutter, of which the two-seat version was named Type D and the single-seat bomber version Type E. Type F was to have been an aeroplane wholly designed by Mann, Egerton & Co., but its construction was abandoned when the firm were urgently called upon to produce the French Spad S.7 in quantity: the Spad was named Mann, Egerton Type G.
  In 1917 the company completed an aeroplane which was entirely of their own design. It was a singleseat fighter for shipboard use, and was designated Type H; it was officially regarded as appropriate to the Admiralty category N.1A. The design work had been done by J. W. Carr. The Type H existed in two different forms; both were powered by a 200 h.p. Hispano-Suiza engine. The first machine, N.44, was known as the Mann, Egerton H.1; and it seems probable that it was designed to the same specification as the Beardmore W.B.IV, for permanent flotation gear was very much in evidence on both aircraft. The Mann, Egerton H.1 was more conventional than the Beardmore, however, and relied upon a wholly external buoyancy chamber to keep it afloat in an emergency; there were additional buoyancy chambers in the rear of the fuselage. The external float attachment ran along the underside of the fuselage from the nose to a point below the cockpit. The undercarriage could be jettisoned before alighting on the water, and wing-tip floats were provided to maintain stability when afloat.
  The two-bay wings could be folded, and there was a slinging attachment above the centre-section. The aileron control cable ran out from the fuselage along the lower wing, over a pulley mounted externally on the rear spar of the lower wing, and then up to the upper aileron. The upper and lower ailerons were interconnected by struts.
  The initial test flights of the Mann, Egerton H.1 were made by Clifford B. Prodger, and it underwent its official trials in October, 1917. It flew well, was said to manoeuvre well and land easily, and was considered suitable for night flying. It failed to pass the flotation test, however.
  The second aircraft, N.45, differed from the first in having no fixed buoyancy chambers. Instead, it was fitted with inflatable air bags of balloon fabric, which could be trimmed by means of a hand pump. This second machine was known as the Mann, Egerton H.2, and its airframe was basically identical to that of N.44. The later aircraft had a larger horn-balanced rudder, and its exhaust pipes were shorter. The H.2 was tested in December, 1917, and was flown at the Isle of Grain.
  Mann, Egerton & Co. built no more aeroplanes of their own design. Until the Armistice, their manufacturing facilities were devoted to the production of the D.H.9 (Mann, Egerton Type J), D.H.9A (Type M), and D.H.10 Amiens (Type N).


SPECIFICATION
  Manufacturers: Mann, Egerton & Co., Ltd., Prince of Wales Road, Norwich.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: 30 ft 9 in. Length: 21ft 11 in. Height: 8 ft 11 1/2 in. Chord: 5 ft 3 in. Gap: 5 ft. Stagger: nil. Dihedral: nil. Incidence: 2° 30'. Span of tail: 10 ft.
  Areas: Wings: 310 sq ft. Ailerons: total 42 sq ft. Tailplane: 18-2 sq ft. Elevators: 17 sq ft. Fin: 4-9 sq ft. Rudder: 7 sq ft.

  Weights (lb) and Performance:
Aircraft H.1 with undercarriage H.1 without undercarriage H.2
Date of Trial Report October 14th, 1917 October 14th, 1917 December 4th, 1917
Type of airscrew used on trial A.B.623 A.B.623 A.B.6238
Weight empty 1,838 1,754 1,760
Military load 54 54 61
Pilot 180 180 180
Fuel and oil 332 322 325
Weight loaded 2,404 2,310 2,326
Maximum speed (m.p.h.) at
6,500 ft 100 100 113
10,000 ft 90 90 I 10
15,000 ft - - 103
m. s. m. s. m. s.
Climb to
6,500 ft 9 10 8 20 6 2.5
10,000 ft 18 00 15 30 12 30
15,000 ft - - - - 28 00
Service ceiling (feet) 12,800 14,700 16,800
Endurance (hours) - - 3 1/4

  Tankage: Petrol: 40 gallons. Oil: 4 gallons.
  Armament: One fixed, forward-firing Vickers machine-gun mounted on top of the fuselage on the port side and synchronised to fire through the airscrew; one Lewis machine-gun on mounting above the centre-section.
  Serial Numbers: The numbers N.44-N.49 were allotted for Mann, Egerton single-seat fighters. Only N.44 and N.45, the H.1 and H.2 respectively, were built. They were ordered under Contract No. A.S. 13905/17.

Mann & Grimmer M.i

  IN the years before the outbreak of the 1914-18 war, Reginald Frank Mann made something of a name for himself while still a schoolboy as the designer of some successful model aeroplanes. In 1913, at the age of 16, he went into partnership with his schoolmaster, Robert P. Grimmer, for the manufacture of model aeroplanes on a commercial basis. Both had shared an interest in aviation since 1908.
  Even before the outbreak of war, Mann had realised that there would be a need for aeroplanes from which a machine-gun could be fired effectively. One of the more remarkable facts in our aeronautical history is that in 1914 the Edward brothers had patented a synchronising gear to enable guns to be fired through the revolving airscrew of a tractor aeroplane: their patent was No. 23790 A.D. 1914. For some reason best known to the War Office, whence a working model of the gear was sent, no more was heard of the device; our designers were obliged to produce pusher machines such as the D.H.2, F.E.2b, F.E.8 and Vickers F.B.5 in order to provide forward-firing armament; and our pilots were confronted in 1915 by enemy aeroplanes with synchronised machine-guns.
  R. F. Mann was aware that, in general, the tractor aeroplanes of the day had a better performance than contemporary pushers, but it was obvious that the frontal airscrew made it impossible, in the absence of any form of synchronising gear, to fit a machine-gun having a forward field of fire. Before the war, Mann and Grimmer had had a desire to produce an aeroplane with twin outboard pusher airscrews, and had secured the interest of W. H. Bonham-Carter in their project.
  The outbreak of war made the need for Service aircraft one of urgency. Convinced of the practicability of his ideas, Mann got out his first design drawings in August, 1914. Mr Bonham-Carter provided most of the cash required, and construction of the Mann & Grimmer M.1 began in September, 1914.
  Design and construction work were pushed forward at great pressure, in the hope that the M.1 might be used against the enemy early in 1915. Work began in the disused church, which was the workshop, at 7 a.m. each morning and continued until midnight on many nights. The completed components were taken to Hendon at the end of January, 1915, and were assembled early in February.
  The basic configuration of the M.1 was that of a two-bay fuselage-type biplane with conventional tail surfaces. The engine installation was quite unlike anything which had been attempted up to that time.
  Power was provided by a 100 h.p. Anzani radial engine, which was installed at the forward end of the fuselage. The engine was mounted backwards, and drove a long shaft which passed under the observer’s seat and terminated in a gear-box amidships. From the gear-box, chains drove two outboard pusher airscrews which, with their shafts and sprockets, were mounted on a diamond-shaped system of wires and struts about the inner rear interplane strut on each side. The gear-box was installed to obviate the need for crossing one of the chains to obtain oppositely-rotating airscrews, but imposed a severe weight penalty, for it weighed 100 lb.
  The pilot sat well behind the wings, and the observer occupied a seat immediately behind the engine. He therefore had an excellent view forwards and a good field of fire for his Lewis gun.
  The undercarriage was originally of the twin-skid type, and the mainplanes had a pronounced taper: the leading edges were swept back.
  The first flight of the Mann & Grimmer M.1 was made by Rowland Ding on February 19th, 1915. This was only a short straight hop, but next day he took the machine clear of the aerodrome. He then found that the rudder was not very effective, no doubt because of the absence of slipstream over it, and the throttle jammed at two-thirds open. However, he succeeded in getting back to the aerodrome safely.
  The chain transmission behaved in a rather alarming fashion, so a month was spent in attempting to improve its functioning; at the same time a larger rudder and improved airscrews were designed. On March 20th the M.1 reached a speed of 70 m.p.h., a figure which was not bettered on two subsequent flights. The performance fell so far short of Mann’s expectations that he decided to replace the 100 h.p. engine by a 125 h.p. Anzani, and the machine was taken back to Surbiton for modification on April 1st, 1915, after less than one hour’s total flying time.
  The new engine required new shafts, sprockets, chains and gear-box. Other modifications included the fitting of a plain vee undercarriage with larger wheels and an even larger rudder, whilst the wires which braced the forward ends of the airscrew shafts were replaced by struts of steel tubes. The stagger was increased, stronger interplane struts were fitted, and new airscrews were installed.
  When flown again on June 29th the machine still did not perform well, and other airscrews were fitted in an attempt to improve performance. On July 4th a stay tube broke and shattered the port airscrew, but Ding brought the M.1 down safely. Ding made a number of later flights on the machine, but Sidney Pickles took over the test flying on August 4th.
  By August 21st the M.1 was flying quite well: the speed was now 75-80 m.p.h., and the initial rate of climb 500 feet per minute. Unfortunately, the terms of Pickles’ contract with an American firm forbade him to fly machines other than those of his firm’s manufacture, and he had to relinquish the flying of the M.1.
  It was not until October 2nd that another pilot was found to fly the Mann & Grimmer machine. He was A. E. Barrs, one of the pre-war Hendon pilots, who had been invalided out of the R.F.C. Barrs made thirty flights on the M.1, some with war load, and reached a height of about 9,000 feet on one occasion. The maximum speed was 85 m.p.h., and its builders claimed that the M.1 was the fastest pusher biplane in existence.
  Various refinements were made to improve performance. The stay tubes supporting the airscrew shafts were carefully faired, and at one time the machine was flown with the inner rear interplane strut removed and a fairing fitted over each outboard sprocket and airscrew shaft. A large spinner-like cowling was fitted over what was normally the rear of the engine. By this time the empty weight was some 800 lb greater than it originally was.
  On November 16th, 1915, Barrs took off with J. G. Woodley in the passenger’s seat in an attempt to break the British altitude record. About 45 minutes after take-off the M.1 was at a height of between 8,000 and 9,000 feet, and was still climbing well when the gear-box seized. The starboard chain broke and vanished into space, and Barrs switched off and began to glide down. The glide lasted 21 minutes, but near the ground bumpy conditions brought the machine down short of the aerodrome. It ran into some trees and was completely wrecked, though neither occupant was injured in any way.
  In its nine months of existence, the M.1 flew for no more than 18 hours, but its builders felt that it had ultimately fulfilled their expectations. After its demise they at once set about the construction of a much improved successor, which was known as the M.2. When half finished the new machine had to be abandoned owing to lack of official support.
  R. F. Mann joined the Army, but within a month contracted a severe cold which ultimately developed into tuberculosis. He was invalided out, and died in Rhodesia some years later.


SPECIFICATION
  Manufacturers: Messrs Marin & Grimmer, Surbiton, Surrey.
  Power: 100 h.p. Anzani; 125 h.p. Anzani.
  Dimensions: Span: 34 ft 9 in. Length: 26 ft 5 in. Gap: 5 ft 9 in.
  Areas: Wings: 322 sq ft.
  Weights: Empty: originally approximately 1,300 lb; in final form about 2,100 lb. Useful load: 700 lb. Weight loaded: approximately 2,800 lb.
  Performance: Maximum speed: 85 m.p.h. Initial rate of climb: 500 ft per minute. Climb to 3,000 ft: 8 min. Endurance: 4 1/2 hours.
  Armament: One free Lewis machine-gun fired by the observer.

Martinsyde S.1

  BEFORE the outbreak of the first World War, Messrs Martin & Handasyde produced a series of monoplanes, of which the later machines were characterised by great beauty of line. By 1914, however, the Avro 504, Bristol Scout and Sopwith Tabloid had made a great impact on the aeronautical world, for they showed that a carefully designed biplane could out-perform contemporary monoplanes.
  The military value of such machines as the Bristol Scout and Sopwith Tabloid was realised in 1914, and the first Martinsyde tractor biplane was a small single-seater in the same general category as the Bristol and Sopwith. (It was not the first Martinsyde biplane, for earlier in 1914 a pusher biplane had been built, powered by a 65 h.p. Antoinette engine.)
  The Martinsyde Scout biplane bore the type number S.1, and was powered by an 80 h.p. Gnome engine. It bore a certain resemblance to the Sopwith Tabloid, largely because of the shape of its engine cowling. The fuselage had rather finer lines than that of the Tabloid, however, and terminated in a tail-unit of pleasing outline. The undercarriage was at first a very sturdy structure which had the form of the twin-skid layout then in favour, but a small wheel was fitted at the forward end of each skid. When on the ground the S.1 rested on the rearward extensions of the main skids, and a small bumping skid was fitted under the sternpost of the fuselage.
  Later Martinsyde S.1s had a plain vee undercarriage in place of the rather clumsy four-wheel affair, and a normal sprung tail-skid was fitted.
  The single-bay wings were conventional in every way, and ailerons were fitted to both upper and lower wings.
  The first production S.1s appeared late in 1914: by the end of that year eleven had been delivered to the R.F.C. Some joined the squadrons in France, but they were few in number and no squadron had more than one or two. On March 10th, 1915, No. 4 Squadron had one Martinsyde S.i and No. 5 Squadron had two; two months later, Squadrons Nos. 1, 5 and 6 had one each.
  The Martinsyde of No. 6 Squadron was flown by Captain L. A. Strange, and he has recorded that he found it to be “a very unstable machine both fore and aft, with not much aileron control”. He went on to say “Although a single-seater, it was hardly superior in speed and climbing power to the Avro which carried two men, but in my eyes all these defects were outweighed by the fact that it had a Lewis gun mounted on its top plane, which could be fired forwards and upwards.”
  That same Lewis gun nearly caused Strange’s death on May 10th, 1915. After emptying a drum of ammunition at an enemy two-seater, he found the drum had jammed. Strange raised himself in his seat and held the stick between his knees in order to have both hands free to work on the drum. He lost his grip on the stick with the Martinsyde in a steep climb; the machine went into an inverted spin and Strange was thrown out, hanging on to the wedged Lewis gun drum. Fortunately the drum did not come off, and he was able to right his aircraft and drop back into his seat after spinning down for more than 5,000 feet.
  In addition to its small-scale use on the Western Front, the Martinsyde S.1 also saw service in the Middle East. On August 26th, 1915, four S.1s arrived at Basra to form the equipment of a second flight of No. 30 Squadron. Their Gnome engines were quite unsuitable for work in the heat and dust of Mesopotamia, and constantly gave trouble.
  On September 7th, two Martinsydes, a Caudron and a Maurice Farman joined the concentration of the 6th Division at Ali Gharbi in preparation for the attack on Kut al Imara. The Farman was wrecked on landing, and one of the Martinsydes crashed a few days later. On the evening of September 16th Major H. L. Reilly, flying the second Martinsyde S.1, carried out a remarkably thorough and useful reconnaissance of the Turkish positions at Es Sinn. On his report, map and sketches Major-General Townshend based his Battle Instructions which resulted in the capture of Kut on September 29th, 1915.
  On September 23rd the two remaining Martinsydes had been sent to Ali Gharbi as reinforcements. By October 6th the three machines had moved to Aziziya, whence the first reconnaissance of Baghdad was made by Captain H. A. Petre. On November 21st Major Reilly’s Martinsyde was shot down and he was captured. By that date one of the others had met an unknown fate, and the last of the Mesopotamian Martinsyde S.is was lost next day after being hit by anti-aircraft fire.
  That marked the end of the S.1s operational career, for the type had been withdrawn from the Western Front in the summer of 1915. The surviving machines went to training units.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 80 h.p. Gnome.
  Dimensions: Span: 27 ft 8 in. Length: 21 ft. Chord: 4 ft pin. Gap: 4 ft 6 in. Stagger: 10 in. Dihedral: 2° 30'. Incidence: 2° 30'.
  Areas: Wings: 280 sq ft. Ailerons: each 7 sq ft, total 28 sq ft. Tailplane: 20 sq ft. Elevators: 13-33 sq ft- Fin: 2-5 sq ft. Rudder: 5-33 sq ft.
  Performance: Maximum speed at ground level: 87 m.p.h.
  Armament: One Lewis machine-gun mounted above the centre-section.
  Service Use: Western Front: R.F.C. Squadrons Nos. 1, 4, 5, 6, 12 and 16. Mesopotamia: No. 30 Squadron, R.F.C. Training Units: School of Instruction, Reading.
  Production and Allocation: Official figures group the Martinsyde S.1 with the G.100 and G.102, and it is not possible to arrive at an accurate total of production S.1s. It seems probable that about sixty were built. Four went to France in 1915 and four to the Middle East Brigade. Training units received four in 1914 and over forty in 1915.
  Serial Numbers: 748, 2451, 2820-2829, 2831, 4241, 4243.

Martinsyde G. 100 and G.102 Elephant

  A NEW Martinsyde single-seat scout was designed and built during the summer of 1915. Designated G.100, it was a handsome biplane with two-bay wing bracing, powered by a 120 h.p. Beardmore engine. The machine was intended to be a long-range fighter, and its generous dimensions were dictated by the need to provide enough wing area to lift petrol for 5 1/5 hours’ flying.
  The first prototype, numbered 4735, was tested at Upavon in September, 1915, and was distinguished by a three-bladed airscrew. The engine cowling was rather an ugly affair which did not blend into the fuselage contours particularly well, and each cylinder of the engine had an individual exhaust stub; the radiator was mounted behind the engine. The undercarriage was a simple vee structure, and each wheel was carried on a half-axle pivoted at the centre point of the spreader bars. The tail-skid was large and sturdy. The low aspect-ratio fin and rudder were of pleasing appearance, and bore a family resemblance to the tail surfaces of the Martinsyde S.1.
  The first production G.100s were delivered at the end of 1915. These machines had a cleaned-up engine cowling with a manifold over the exhaust ports, and a two-bladed airscrew was used. All flying wires were double on the production aircraft, and a lighter pylon-type tail-skid was fitted.
  The Martinsyde G.100 appeared before an effective British machine-gun interrupter gear was available. The armament had to be disposed in such a way that the guns avoided the airscrew, so the machine was fitted with a Lewis gun above the centre-section and, rather curiously, a second Lewis on a mounting behind the cockpit on the port side. The latter was for firing rearwards.
  The machine was officially known as the Martinsyde Scout, as had been its predecessor, the Martinsyde S.1. Official records and statistics are therefore not explicit in dealing with either type.
  The first few G.100s which went to France early in 1916 were distributed to various squadrons in small numbers. They were then used as escorts for the two-seaters which formed the main equipment of the units. The first and only squadron to go to France equipped throughout with Martinsydes was No. 27, which arrived there on March 1st, 1916.
  Their first task was to escort reconnaissance and bombing aircraft, a duty for which their long range made them suitable, and they were thus employed until the Battle of the Somme was under way. Offensive patrols were also carried out, but the Martinsyde was not at its best in combat. It was not quite so quick to answer the controls as were most other contemporary fighting scouts, and the pilot’s view from his seat was somewhat obstructed by the disposition and unusually large chord of the wings. A flying quality which was regarded as a fault by most pilots of its day was the Martinsyde’s prolonged float before touching down. This float was in fact a testimonial to clean design, but seemed a strange phenomenon to pilots who were more accustomed to aeroplanes whose drag was high, and which sat down without floating as soon as the throttle was closed and the stick drawn back for the touch-down.
  If the Martinsyde G.100 did not make a name for itself as a single-seat fighter, its good load-carrying capabilities enabled it to be effectively employed as a bomber. In this capacity No. 27 Squadron flew its Martinsydes until they were replaced by D.H.4s in November, 1917.
  The squadron’s first systematic bombing operations began during the Battle of the Somme. On July 1st, 1916, the day the Somme offensive was launched, six Martinsydes bombed Bapaume, which was known to contain a German headquarters. Thereafter No. 27 Squadron made many bombing attacks in the area south of the Ancre: repeated attacks were made on such villages as Beaulencourt, Le Transloy and Sailly-Saillisel, which were usually full of enemy troops and stores.
  Ample proof of the Martinsyde’s great strength was given on September 23rd, 1916, when, in the course of a fight, the machine flown by Second Lieutenant L. F. Forbes of No. 27 Squadron collided with a German machine. The enemy crashed at once, but Forbes’s Martinsyde survived the collision with a badly damaged wing. Forbes managed to evade all further enemy attacks and flew his machine back to No. 24 Squadron’s aerodrome. After this gallant flight he was severely injured on landing, for the Martinsyde became completely uncontrollable when he tried to close the throttle for landing.
  In 1916, the Martinsyde was improved by the installation of the 160 h.p. Beardmore engine which, although not so mechanically reliable as the 120 h.p. version, improved the aeroplane’s weight-lifting capabilities. By this time the exhausts consisted of three stubs on the port side. The new type designation G.102 was applied to the modified machine, and it was at about this time that the nickname “Elephant” began to be used. The origin of the name has been attributed to the Martinsyde’s proportions which, for a single-seater and particularly one intended for fighting, were large. The name was unofficial, but was widely used.
  The new engine enabled the Martinsyde G.102 to carry two 112-lb bombs or one 230-pounder in place of the single 112-lb bomb carried by the G.100. Four of No. 27 Squadron’s Martinsydes, led by Captain P. C. Sherren, delivered their eight 112-pounders in telling fashion on the railway junction at Hirson on November 16th, 1916. Escorted by two further Martinsydes, the Elephants bombed from 1,000 feet, and their missiles blew six coaches off the track, destroyed rolling-stock in the siding and demolished two station buildings. All the Elephants returned after a 4 1/2-hour flight.
  Throughout the Battle of Arras, Messines and Ypres the Elephants carried out bombing attacks on various objectives. One of the finest flights made by an Elephant was the attack on the airship sheds at Gontrode made on November 1st, 1917, by Sergeant S. J. Clinch of No. 27 Squadron. His machine was one of three which took off for that objective, but his two companions became lost in the cloud and poor visibility. Flying solely by compass, Clinch flew on gamely and came out of the clouds directly over his target. Diving to the level of the roofs of the sheds he dropped his bombs and flew back to his aerodrome, again by compass.
  At least one Martinsyde was fitted with a Lewis gun pointing upwards at an angle of about 45 degrees. The gun was mounted on the starboard side of the cockpit and fired through the centre-section. The pilot had an Aldis sight mounted parallel to the gun. This installation may have been made as part of the experiments conducted at Orfordness with upward-firing guns. It is also recorded that a Martinsyde G.102 fitted with the Eeman gun gear was tested in August, 1917.
  The Martinsyde was used overseas, and saw service in Palestine and Mesopotamia. In Palestine, Squadrons Nos. 14 and 67 each had a few, which carried out bombing attacks. On March 22nd, 1917, these squadrons had between them fourteen Martinsydes, nine of which were serviceable on that date. Each squadron supplied one Martinsyde for an attempt to cut the Hejaz railway on November 24th, 1916. Captain R. H. Freeman of No. 14 Squadron dropped two 100-lb bombs on the railway bridge south of Qal’at el Hasa but failed to destroy it, while Lieutenant S. K. Muir of No. 67 (Australian) Squadron attacked the station at Jurf ed Derawish with one 100-lb and four 20-lb bombs. This sortie entailed a five-hour flight.
  One of the most remarkable fighting machines of any kind to see use during the war was “Mimi”. Mimi consisted of a Martinsyde G.102 fuselage, stripped of wings, tail unit and covering, mounted on floats and armed with two machine-guns. Mimi was made at the suggestion of Lieutenant-Colonel R. Williams as a means of harassing Turkish shipping in the Dead Sea. She was erected by the Dead Sea on February 28th, 1918; and next day, manned by Captain J. A. D. Dempsey, Captain P. D. Drury and First-Class Air Mechanic Doig, she set out to capture a group of boats on the eastern shore. On the outward journey the rudder yoke broke, and Mimi drifted southwards until she was beached. Only the floats were used subsequently; the Martinsyde fuselage was abandoned.
  Six Martinsyde G.100s arrived in Mesopotamia in September, 1916, and were used by No. 30 Squadron for bombing and reconnaissance. Just over a year later, a few Martinsydes were on the strength of one Flight of No. 63 Squadron, and “B” Flight of No. 72 Squadron was equipped with the type. The latter squadron arrived at Basra on March 2nd, 1918, and “B” Flight was at first based at Baghdad; at the end of May the Flight moved to Kazvin.
  The Martinsydes of No. 72 Squadron assisted in the campaign against the Jangalis, fought by “Dunsterforce”, the British force commanded by Major-General L. C. Dunsterville. On June 21st, 1918, two Elephants bombed the Jangali barracks at Kasma and did considerable damage. Some three weeks later, two Martinsydes assisted in the severe defeat inflicted on the Jangalis at Resht, and a ten-day bombing and strafing offensive made by the aircraft induced the Jangali leader Kuchik Khan to sue for peace.
  In the fighting around Baku in September, 1918, two Elephants flown by Lieutenants M. C. McKay and R. P. P. Pope gave admirable service. When the British force withdrew from the town the Martinsydes had to be burned. Their pilots thereafter fought with the infantry.
  The Martinsyde Elephant did not survive the Armistice, but its name and its association with No. 27 Squadron are perpetuated by the inclusion of an elephant in the badge of the squadron.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: G.100: 120 h.p. Beardmore; G.102: 160 h.p. Beardmore.
  Dimensions: Span: 38 ft. Length: G.100, 26 ft 6 in.; G.102, 27ft. Height: 9 ft 8 in. Chord: 5 ft 11 3/4 in. Gap: 5 ft 8 in. Stagger: 18 in. Dihedral: 2°. Incidence: 30. Span of tail: 13 ft 6 in. Airscrew diameter: 9 ft 6 in. Wheel track: 6 ft 0 5/8 in. Tyres: 700 X 100 mm.
  Areas: Wings: 410 sq ft. Ailerons: each 10-5 sq ft, total 42 sq ft. Tailplane: 26 sq ft. Elevators: 21 sq ft. Fin: 4-75 sq ft. Rudder: 10 sq ft.
  Armament: One Lewis machine-gun above the centre-section; a second Lewis gun on mounting behind the cockpit on the port side. The bomb load varied considerably, and could consist of one 230-lb bomb, two 112-pounders, two 100-pounders, or four 65-pounders. The large bombs were usually carried under the fuselage, and there were racks under the wings for lighter bombs.
  Service Use: Western Front: R.F.C. Squadrons Nos. 18, 20, 21, 23 and 27. Palestine: Squadrons Nos. 14 and 67 (Australian). Mesopotamia: Squadrons Nos. 30, 63 (one Flight) and 72 (“B” Flight). Training: Central Flying School, Upavon; No. 10 Reserve Squadron, Joyce Green; No. 31 Training Squadron, Wyton; No. 39 Training Squadron, Narborough; Training Squadron at Dover; No. 51 Squadron.
  Production and Allocation: Approximately 300 Martinsyde G.100s and G.102s were built. One hundred and thirty-three went to the squadrons in France, and sixty-four to the Middle East Brigade. One was sent to a Home Defence squadron in 1917, and the remainder went to training units.
  Serial Numbers: 4735-4736; 7258-7307; 7459-7508; A.1561-A.1610; A.3935-A.4004; A.6250-A.6300. B.865.
  Notes on Individual Machines: Used by No. 27 Squadron: 7266, 7464, 7469, 7478, 7492, 7495, 7499, 7500, 7501, 7503, 7504, 7506, A.1566, A.1567, A.1572, A.1573, A.1579, A.1599, A.3976, A.3977, A.3986, A.3990, A.3992, A.3993, A.4004, A.6250, A.6251, A.6258, A.6259, A.6262, A.6263, A.6287, A.6288, A.6290, A.6291. Used by No. 67 (Australian) Squadron: A.1600, A.3945, A.3946, A.3955. Other machines: 7294: No. 51 Squadron. A.3996: No. 10 Reserve Squadron. A.4002: No. 51 Squadron. A.6252: Training Squadron at Dover.
Weights (lb} and Performance:
Aircraft G.100 G.102 G.102 with Eeman gun gear
No. of Trial Report - M.80 M.130
Date of Trial Report - January, 1917 August, 1917
Type of airscrew used on trial L.P.920 L.P.2400 L.P.2400
Weight empty 1,759 1,793 -
Military load 64 96 134
Pilot 180 180 180
Fuel and oil 421 389 -
Weight loaded 2,424 2,458 2,370
Maximum speed (m.p.h.) at
ground level - 103-1 -
2,000 ft - 104 -
3,000 ft - 103-7 -
6,500 ft 95 102 98-5
10,000 ft 87 99-5 97
14,000 ft - 93-5 -
m. s. m. s. m. s.
Climb to
1,000 ft - - 1 00 - -
3,000 ft - - 3 30 - -
6,000 ft - - 8 05 - -
6,500 ft 10 00 - - 10 00
10,000 ft 19 00 15 55 17 50
12,000 ft - - 21 10 - -
14,000 ft - - 29 00 - -
16,000 ft - - 40 45 - -
17,000 ft - - 49 30 - -
Service ceiling (feet) 14,000 16,000 17,500
Endurance (hours) 5 1/2 4 1/2 -

Martinsyde R.G.

  TOWARDS the end of 1916, a new single-seat fighter was built at the Martinsyde works. This was the R.G., a single-bay biplane powered by the 190 h.p. Rolls-Royce Falcon engine. Its descent from the Martinsyde G.100 was apparent in its clean lines and the shape of its tail unit.
  Its overall dimensions were smaller than those of the Elephant, and it had the appearance of being an excellent fighter. The fuselage was deeper than that of its predecessor, and the incidence of the tailplane could be controlled from the cockpit. A car-type frontal radiator was fitted, and twin synchronised Vickers guns were mounted in front of the cockpit.
  The R.G. was tested at Farnborough in February, 1917, and its performance was excellent. It was perhaps unfortunate, as far as its own future was concerned, that the R.G. was powered by the engine which was earmarked for the Bristol Fighter; and the official decision to produce the S.E.5 and Sopwith Camel had already been taken. These were no doubt regarded as cogent reasons against the production of the R.G., but it seems regrettable that such a promising design had to be abandoned.
  The R.G.’s performance was further enhanced when it was later fitted with the 275 h.p. Rolls-Royce Falcon III engine. It was tested with the new power-unit in June, 1917.

SPECIFICATION

Weights (lb) and Performance:
Engine Falcon I Falcon III
No. of Trial Report M.81 M.i 12
Date of Trial Report February, 1917 June, 1917
Type of airscrew used on trial Lang 3090 Lang
Weight empty 1,730 1,740
Military load 110 101
Pilot 180 180
Fuel and oil 214 240
Weight loaded 2,234 2,261
Maximum speed (m.p.h.) at
ground level 130 -
6,500 ft 126-5 132
8,000 ft 125 -
10,000 ft 122 130
12,000 ft 119-5 -
15,000 ft 115 127-5
18,000 ft 108 -
m. s. m. s.
Climb to
1,000 ft 0 45 - -
6,500 ft 5 55 4 10
10,000 ft 10 20 7 20
12,000 ft 13 30 - -
14,000 ft 17 15 - -
15,000 ft 19 20 12 50
16,000 ft 21 45 - -
18,000 ft 27 30 - -
19,000 ft 30 55 - -
Service ceiling (feet) 22,000 23,500
Endurance (hours) 1 3/4 2

  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 190 h.p. Rolls-Royce Falcon I; 275 h.p. Rolls-Royce Falcon III.
  Dimensions: Span: upper 32 ft, lower 30 ft. Length: Falcon I, 25 ft 8 in.; Falcon III, 25 ft 10 in. Height: 9 ft 10 in. Chord: 5 ft. Gap: 5 ft 6 in. Stagger: 1 ft 10 in. Dihedral: 2 30'. Incidence: 3.
  Areas: Wings: 310 sq ft. Ailerons: total 32 sq ft. Tailplane: 23 sq ft. Elevators: 18 sq ft. Fin: 4 sq ft. Rudder: 11 sq ft.
  Tankage: Petrol: 26 gallons. Oil: 3 gallons. Water: 5 gallons.
  Armament: Two fixed and synchronised forward-firing Vickers machine-guns mounted on top of the fuselage in front of the cockpit.
  Serial Numbers: The serial numbers A.318-A.320 were allotted for a Martinsyde type, and may have been appropriate to the R.G.

Martinsyde F.1

  THE first of the Martinsyde F series was a large two-seat biplane, powered by the 250 h.p. Rolls-Royce Mk. Ill engine, which was tested in the summer of 1917. The F.1 was intended to be a two-seat fighter, but its large size and the peculiar (at that late date) seating arrangements would have detracted seriously from its performance in that capacity.
  The observer occupied the forward cockpit, whence he could observe very little outside the aircraft, for he sat directly under the upper wing and over the lower. Ingress to the front cockpit was gained via a large rectangular cut-out in the centre-section. The mainplanes were of unequal chord, and the fuselage was mounted about midway between them, as on the Bristol Fighter. There was no wing surface immediately under the fuselage; the lower centre-section was an open structure.
  The fuselage was basically similar to that of the Elephant, but was suitably strengthened to take the more powerful Rolls-Royce engine. The tailplane and elevators appeared to be identical to those of the earlier type.
  The official report on the Martinsyde F.1 ran as follows:
  “The observer is in the front seat, and there is no fixed gun firing forward. The testing squadron suggested it would be a decided improvement, in extent of view and fire, if positions of pilot and observer were reversed, while machine would be better able to resist a strong attack from below. Flying qualities, stability, and controllability good; magneto, carburettors, tanks, etc., very inaccessible.”
  It seems, however, that the type was never developed; and it is doubtful whether any attempt was made to install armament. No guns or mountings were fitted when the F.1 was delivered to the Testing Squadron, and its performance tests were conducted with ballast of 185 lb to represent the standard reconnaissance load for two-seat aircraft.
  Since it was the first of the Martinsyde F series, the F.1 was known in the works as “Father”.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 250 h.p. Rolls-Royce Mk. Ill (284 h.p. Eagle III).
  Dimensions: Span: upper 44 ft 6 in., lower 44 ft 2 in. Length: 29 ft 1 in. Height: 8 ft 6 in. Chord: upper 6 ft 8 in., lower 5 ft 10 in. Gap: 6 ft. Stagger: 1 ft 7 in. Dihedral: 30. Incidence: 30. Tyres: 750 X 125 mm. Airscrew diameter: 9 ft 7 in.
  Areas: Wings: 467 sq ft. Ailerons: total 54 sq ft. Tailplane: 26 sq ft. Elevators: 21 sq ft. Fin: 5 sq ft. Rudder: 11 sq ft.
  Weights and Performance: No. of Trial Report: M.115. Date of Trial Report: July, 1917. Type of airscrew used on trial: Lang, Series No. 9334. Weight empty: 2,198 lb. Military load: 185 lb. Crew: 360 lb. Fuel and oil: 517 lb. Loaded: 3,260 lb. Maximum speed at 6,500 ft: 109-5 rn.p.h.; at 10,000 ft: 104-5 m.p.h.; at 13,000 ft: 98-5 m.p.h.; at 15,000 ft: 94m.p.h.; at 16,500 ft: 89 m.p.h. Climb to 1,000 ft: 1 min; to 6,000 ft: 6 min 55 sec; to 10,000 ft: 13 min 40 sec; to 12,000 ft: 18 min 35 sec; to 14,000 ft: 25 min 20 sec; to 16,000 ft: 36 min 20 sec. Service ceiling: 16,500 ft. Endurance: 3 3/4 hours.
  Tankage: Petrol: 66 gallons. Oil: 5 1/2 gallons. Water: 6 gallons.
  Serial Numbers: A.3933-A.3934, ordered under Contract No. 87/A/435.

Martinsyde F.2

  THE second Martinsyde two-seater of the F series was a fighter-reconnaissance machine of compact design and purposeful appearance. It was a single-bay biplane with the same overall dimensions as the Martinsyde R.G. fighter, and had quite a good performance. It was tested in May, 1917.
  The pilot’s and observer’s cockpits were situated close together, but the pilot’s view from his position under the centre-section was very limited, and was adversely criticised in the official report on the aircraft. The F.2 was structurally conventional, and emergency dual control was provided in the rear cockpit.
  The aircraft’s greatest drawback was the poor outlook from the pilot’s cockpit; but apart from that the Martinsyde machine arrived at a time when the Bristol Fighter was proving itself to be highly successful and was in large-scale production. A further point which minimised the F.2’s chances of being built in quantity was its use of the 200 h.p. Hispano-Suiza engine, which at that time was in great demand for the S.E.5a.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: upper 32 ft, lower 30 ft. Length: 25 ft. Height: 8 ft 2 in. Chord: 6 ft. Gap: 5 ft 3 in. Stagger: 2 ft. Dihedral: 2°. Incidence: 2° 30'. Tyres: 700 X 100 mm. Airscrew diameter: 9 ft 2 1/2 in.
  Areas: Wings: 334 sq ft. Ailerons: total 48 sq ft. Tailplane: 24 sq ft. Elevators: 19 sq ft. Fin: 4-25 sq ft. Rudder: . 9-75 sq ft.
  Weights and Performance: No. of Trial Report: M.98. Date of Trial Report: May, 1917. Type of airscrew used on trial: Lang, Series No. 3290. Weight empty: 1,547 lb. Military load: 185 lb. Crew: 360 lb. Fuel and oil: 263 lb. Loaded: 2,355 lb. Maximum speed at ground level: 120 m.p.h.; at 10,000 ft: 114 m.p.h.; at 15,000 ft: 107 m.p.h. Climb to 1,000 ft: 1 min; to 6,500 ft: 7 min 42 sec; to 10,000 ft: 13 min 30 sec; to 12,000 ft: 17 min 42 sec; to 14,000 ft: 23 min; to 15,000 ft: 26 min 18 sec; to 16,000 ft: 30 min 30 sec. Service ceiling: 17,000 ft. Endurance: 2 1/2 hours.
  Tankage: Petrol: 33 gallons. Oil: 3 1/4 gallons.
  Armament: One fixed and synchronised forward-firing Vickers machine-gun mounted in front of pilot’s cockpit to port of centre; one Lewis machine-gun on Scarff ring-mounting on rear cockpit.

Martinsyde F.3

  THE Martinsyde F.3 was the first single-seat fighter of the F series, and was therefore popularly known at the Martinsyde works as “Mother”: the nickname was, of course, cognate with that of the F.1, “Father”.
  The F.3 was a single-bay biplane, originally powered by an experimental version of the Rolls-Royce Falcon engine which gave 285 h.p. It bore quite a strong family resemblance to the F.2 two-seater. The fuselage was unusually deep, and carried at its forward end a rectangular frontal radiator. The pilot sat fairly high and in line with the trailing edge of the upper wing.
  Structurally the F.3 was typical of the period, but much care had been taken to reduce drag. Particular evidence of this was afforded by the careful fairing of the lower wing roots and rear spar to the bottom of the fuselage. The machine-guns were mounted under the cowling.
  The F-3 was first tested in November 1917, and proved to have an excellent performance. It was in fact officially described as “a great advance on all existing fighting scouts.” It was later (in May, 1918) flown with a standard Falcon III, for which engine shutters were added to the radiator.
  At the time of the F.3’s appearance, the demand for Rolls-Royce engines greatly exceeded the supply. The 300 h.p. Hispano-Suiza was therefore substituted for the Falcon, and in this form the aeroplane was prepared for production. The design was modified in certain other respects, however, and was given the new type number F.4.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 285 h.p. Rolls-Royce Falcon Experimental; 275 h.p. Rolls-Royce Falcon III; 300 h.p. Hispano-Suiza.
  Dimensions: Span: upper 32 ft 10 in., lower 31 ft 6 in. Length: Falcon Experimental, 25 ft 8 in.; Falcon III, 25 ft 6 in. Height: 8 ft 8 in. Chord: 6 ft. Gap: 5 ft 3 in. Stagger: 2 ft. Dihedral: 2. Incidence: 2.
  Areas: Wings: 320 sq ft. Ailerons: each upper 11-75 sq ft, each lower 9-25 sq ft, total 42 sq ft. Tailplane: 20-25 sq ft. Elevators: 16-5 sq ft. Fin: 6-5 sq ft. Rudder: 9-75 sq ft.

Weights (lb) and Performance:
Engine Falcon Experimental Falcon III
No. of Trial Report M.158 M.200
Date of Trial Report November, 1917 May, 1918
Type of airscrew used on trial Lang 3770 Lang 3770
Weight empty 1,790 1,859
Military load 101 124
Pilot 180 180
Fuel and oil 254 283
Weight loaded 2,325 2,446
Maximum speed (m.p.h.) at
ground level 142 -
6,500 ft - -
10,000 ft 138 129-5
15,000 ft 132-5 123-5
16,500 ft 130-5 -
m. s. m. s.
Climb to
6,000 ft 3 35 - -
6,500 ft 4 00 4 40
10,000 ft 6 50 8 05
15,000 ft 11 55 15 00
20,000 ft 24 30 - -
Service ceiling (feet) 24,000 21,500
Endurance (hours) 2 1/2 2 1/4

  Armament: Two fixed forward-firing Vickers machine-guns mounted under the cowling and synchronised to fire through the revolving airscrew.
  Service Use: Used at Home Defence stations, possibly by No. 39 Squadron.
  Production and Allocation: Six F.3s were ordered. According to official figures, four were sent to Home Defence units in 1918.
  Serial Numbers: B.1490-B.1495, ordered under Contract No. A.S.29238.
  Costs:
   Airframe without engine, instruments and guns:
   (1) for Rolls-Royce Falcon III £1,155
   (2) for 300 h.p. Hispano-Suiza £1,210
   Rolls-Royce Falcon III engine £1,210



Martinsyde F.4, the Buzzard

  WHEN the basic F.3 design was modified for production as the F.4 with the 300 h.p. Hispano-Suiza engine, the opportunity was taken to move the pilot’s seat farther aft. This placed him behind the upper wing and greatly improved his view. Otherwise the machine was little changed, and it was still a clean single-bay biplane with a deep, commodious fuselage, structurally similar to the F.3.
  The F.4 was tested in June, 1918, but the original performance figures were slightly improved two months later when pistons of a new type were fitted to the engine.
  Large orders were placed for the type, but none had reached the squadrons before the Armistice was signed. The F.4, officially named Buzzard Mk. I, was the fastest British aeroplane in production at the end of the war, and would have had a considerable influence on the war if the Armistice had not intervened. A special long-range version designated Buzzard Mk. la was scheduled for production at the time of the Armistice, and was presumably intended for service with the Independent Force.
  It seems rather strange that the much slower Sopwith Snipe was preferred as the standard singleseat fighter of the post-war R.A.F., the more so because the Martinsyde F.4 anticipated, particularly in its handling qualities, fighters of later years. It was fully aerobatic and thoroughly manoeuvrable, but its turning radius was larger than that of its predecessors.
  Had the war lasted a few months longer, American-built Martinsyde F.4s would have been in service. A contract for 1,500 machines was cancelled with the signing of the Armistice.
  Two Martinsyde F.4s were used by the R.A.F. Communication Wing in 1919 for emergency flights between London and Paris during the Peace Conference. One F.4 flown by Lieutenant-Colonel W. H. Primrose covered the 215 miles in 1 hour 15 minutes, a record for the Communication Wing.
  An F.4 with a 275 h.p. Rolls-Royce Falcon III participated in the 1919 Aerial Derby, and the years after the Armistice saw a number of experimental variants of the design. A floatplane version was built, and a two-seat reconnaissance version was produced. Another F.4 had a plain nose and a pair of Lamblin radiators between the undercarriage legs. For sporting purposes a two-seat version was built.
  Among the types of British aeroplanes which were taken to Japan in 1921-22 by the British Aviation Mission to the Imperial Japanese Navy was one Martinsyde F.4. It and an S.E.5a were supplied as samples of single-seat fighters with stationary engines, and the two aircraft exercised a considerable influence on early Japanese design. The Mitsubishi S-81 and S-81-2 single-seat fighters, S-82 two-seat fighter and T-81 two-seat reconnaissance machine all showed strong Martinsyde influence.
  When the Martinsyde company closed down, the Aircraft Disposals Co. offered the surplus F.4s forsale, and later produced their own version of the aircraft under the designation Martinsyde A.D.C.1. This variant had an Armstrong Siddeley Jaguar engine. A number were sold to Finland and were used as single-seat fighters.


SPECIFICATION
  Manufacturers: Martinsyde, Ltd., Brooklands, Byfleet.
  Power: 300 h.p. Hispano-Suiza; 275 h.p. Rolls-Royce Falcon III.
  Dimensions: Span: upper 32 ft 9 3/8 in., lower 31 ft 2 3/8 in. Length: 25 ft 5 5/8 in. Height: 10 ft 4 in. Chord: upper
6 ft 0 1/2 in., lower 5 ft 6 1/4 in. Gap: 5 ft 24 in. Stagger: 2 ft. Dihedral: 2°. Incidence: 2°. Span of tail: 11 ft 2 1/2 in. Airscrew diameter: 8 ft 8 7/8 in.
  Areas: Wings: 320 sq ft. Ailerons: each upper 11-75 sq ft, each lower 9-25 sq ft, total 42 sq ft. Tailplane: 20-25 sq ft. Elevators: 16-5 sq ft. Fin: 6-5 sq ft. Rudder: 9-75 sq ft.

Weights (lb) and Performance:
Aircraft Prototype F.4 Prototype with modified pistons Production F.4
No. of Trial Report M.210A M.210B M.257
Date of Trial Report June, 1918 August, 1918 May, 1919
Type of airscrew used on trial Lang 5270 Lang 52 70A Lang 5270B
Weight empty 1,710 1,710 1,811
Military load 101 101 101
Pilot 180 180 180
Fuel and oil 298 298 306
Weight loaded 2,289 2,289 2,398
Maximum speed (m.p.h.) at
ground level 145 - -
6,500 ft 144 144-5 -
10,000 ft 142-5 143-5 -
13,000 ft 1395 - -
15,000 ft 136-5 139-5 132-5
16,500 ft 134 - -
19,500 ft 127-5 - -
20,000 ft 126 - -
m. s. m. s. m. s.
Climb to
5,000 ft 3 00 - - - -
6,500 ft 4 00 4 00 4 40
10,000 ft 6 40 6 55 7 55
13,000 ft 9 30 - - - -
15,000 ft 11 45 12 20 14 00
16,500 ft 13 40 - - - -
19,500 ft 18 30 - - - -
20,000 ft 19 20 - - - -
Service ceiling (feet) 25,000 26,000 24,000
Endurance (hours) 2 1/2 - -

  Tankage: Petrol: 38 gallons. Oil: 3 1/2 gallons. Water: 4 gallons.
  Armament: Twin fixed synchronised Vickers machine-guns mounted under the cowling firing forward through the airscrew. A small bomb load could be carried.
  Production: On October 31st, 1918, the R.A.F. had fifty-two Martinsyde F.3s and F.4s on charge. Of these, seven were under test, one was at an Aircraft Acceptance Park, and the other forty-four were in store.
  Serial Numbers: D.4211-D.4360; between and about H.7780 and H.7786.
  Costs: Airframe without engine, instruments and guns L1,142 2s.

Nieuport B.N.1

  THE British Nieuport and General Aircraft Co., Ltd., was formed before the outbreak of war for the manufacture of Nieuport designs under licence in the United Kingdom. It was one of the group of firms founded by Samuel Waring (later Lord Waring) of Messrs Waring & Gillow.
  One of the chief products of the company was the Sopwith Camel, of which several hundreds were built, but design work was undertaken by the British Nieuport company after Major S. Heckstall-Smith and H. P. Folland, formerly of the Royal Aircraft Factory, joined the staff of the firm in 1917.
  The first British Nieuport design was a single-seat fighter powered by the Bentley B.R.2 engine and designated B.N.1. Work on the design began in March, 1918, and when the completed aircraft emerged it showed that Mr Folland had not forgotten some of the constructional features which had placed the S.E.4 so far in advance of all its contemporaries in 1914.
  The unstaggered wings of the B.N.1 were of unequal chord and had two-bay bracing, but the interplane struts were of the I-type, as were those of the S.E.4. As originally built, the B.N.1 had a large conical spinner which, with the juxtaposition of the close engine-cowling and rather narrow undercarriage vees, was strongly reminiscent of the S.E.4. The spinner was later removed.
  In its construction the B.N.1 incorporated a number of S.E.5 components, the most obvious of which were the tail-skid and lower fin. The fuselage was a simple box girder with rounded top-decking and side fairings behind the engine cowling.
  The armament consisted of twin Vickers guns and a single Lewis gun on a special mounting above the centre-section: the latter weapon fired at a slight upward angle, and could be pulled down for reloading and firing upwards. The B.N.1 therefore had the same armament arrangement as the prototype Sopwith Snipe, the Austin A.F.T.3, and the original designs of the Armstrong Whitworth Armadillo and Boulton & Paul Bobolink.
  The B.N.1 was a promising design in many ways, and its performance was excellent. It was not developed, however, doubtless because of the official adoption of the Snipe as the B.R.2-powered successor to the Camel. Moreover, the Nieuport company were already engaged on the design of the Nighthawk by the summer of 1918.


SPECIFICATION
  Manufacturers: The Nieuport and General Aircraft Co., Ltd., Cricklewood, London, N.W.
  Power: 230 h.p. Bentley B.R.2.
  Dimensions: Span.: 28 ft. Length: 18 ft 6 in. Height: 9 ft. Chord: upper 6 ft, lower 4 ft 2 in. Gap: 4 ft 3 in. Dihedral: 3. Airscrew diameter: 9 ft 3 in.
  Areas: Wings: 260 sq ft. Tailplane: 18 sq ft. Elevators: 10 sq ft. Fin: 5-2 sq ft. Rudder: 5 sq ft.
  Weights: Loaded: 2,030 lb.
  Performance: Maximum speed at 15,000 ft: 127 m.p.h. Climb to 15,000 ft: 16 min. Ceiling: 26,000 ft. Endurance: 3 hours.
  Tankage: Petrol: 36 gallons.
  Armament: Two fixed and synchronised Vickers machine-guns mounted on top of the fuselage and firing forward through the airscrew; one Lewis machine-gun on sliding mounting above the centre-section to starboard of centre, firing forwards and upwards over the airscrew.
  Serial Numbers: C.3484-C.3486.

Nieuport Nighthawk

  THE second British Nieuport type was another single-seat fighter designed by H. P. Folland. This machine was named Nighthawk, and was powered by a 320 h.p. A.B.C. Dragonfly nine-cylinder radial engine.
  Like the B.N.1, the Nighthawk was a two-bay biplane, but its bracing was more conventional: four pairs of parallel interplane struts connected the staggered wings. The tail-unit was virtually identical to that of the B.N.1, and retained the S.E.5 under-fin and tail-skid; but the fuselage was faired out to a rounded cross-section throughout its length. With an eye to rapid production, the Nighthawk incorporated several other S.E.5 parts: these included fuselage fittings, stick and rudder bar, and the axle and wheels.
  In the air, the Nighthawk was supremely manoeuvrable, and its agility made it an excellent aerobatic mount. Its performance in terms of miles per hour and rate of climb was also extremely good, and there can be no doubt that it would have proved to be a good fighting aeroplane.
  The Nighthawk went into production late in 1918, but it is perhaps fortunate that it did not see operational service. It has been said that, if the war had lasted some months longer than it did, the Dragonfly engine would have lost it for Britain at least.
  It was, of course, almost inevitable that the Dragonfly should have been chosen for the Nighthawk; and in fact the Nighthawk was the first Dragonfly-powered aircraft to be ordered in quantity.
  Mr Granville Bradshaw initiated design work on the Dragonfly after A.B.C. Motors, Ltd., had received an official invitation, in April, 1917, to submit designs for the 1918 engine programme. The company was given an order for three experimental engines, to be called Dragonfly, in August, 1917. The initial success of the smaller A.B.C. Wasp in its early trials encouraged Bradshaw to press his new design upon the Government. He claimed that the Dragonfly would deliver 340 h.p. for a weight of a little over 600 lb, and suggested that it would be preferable to build the Dragonfly rather than the Wasp. Like the Wasp, the Dragonfly was designed for ease of production; and it offered such great power that it was a very attractive proposition.
  In October, 1917, the Air Board had decided to order the Bentley B.R.2 rotary engine in quantity, and by the middle of that month orders had been placed of sufficient size to ensure an ultimate production of 900 B.R.2 engines per month. Two days after the Air Board had made its decision, however, the Dragonfly was brought to the notice of the Board’s members.
  Mindful of its unfortunate experiences arising out of the ordering of the untried Sunbeam Arab, the Board approached the Dragonfly with caution. The members felt that they could not afford to pass over an engine which seemed so full of promise; but they did not want to cancel or reduce the production of B.R.2s in favour of an untried design. The B.R.2 programme was therefore not disturbed, and Vickers, Ltd., were asked to produce the Dragonfly at their Crayford works as a first step.
  As 1918 advanced, both the Air Board and the aircraft industry became more and more convinced that the Dragonfly was the best engine available, and large contracts were placed during the year. Altogether, 11,050 were ordered from thirteen contractors* and the ultimate intention was for the Dragonfly to supersede most other engines in production. The production programme was planned to ensure delivery of 4,135 Dragonflies by the end of June, 1919.
* The contractors and the numbers of Dragonfly engines ordered from each were these: Beardmore Aero Engine, Ltd.: 1,500; Crossley Motors, Ltd.: 1,000; Ransome, Sims & Jeffries: 500; F. W. Berwick & Co., Ltd.: 1,000; Belsize Motors, Ltd.: 1,000; Maudslay Engineering Co., Ltd.: 500; Vulcan Motor & Engineering Co., Ltd.: 600; Vickers, Ltd.: 1,000; Sheffield Simplex: 500; Guy Motors, Ltd.: 600; Clyno Engineering Co.: 500; Ruston, Proctor & Co., Ltd.: 1,500; Humber, Ltd.: 850.
  After the engine was in production, however, it was found to be far from satisfactory. It was heavier than the original estimate; gave less power; and, worst of all, vibrated exceedingly badly in flight tests. Mechanical failure usually occurred after only a few hours’ flying. New pistons were fitted, and late in 1918 cylinder heads of the type developed at the Royal Aircraft Establishment by Professor A. H. Gibson and S. D. Heron were installed.
  But the engine suffered from dynamic unbalance and synchronous torsional vibration in an extreme degree. The latter phenomenon was not understood in 1918, but it began to be realised that a complete re-design of the engine would have to be undertaken in order to cure the trouble. Before production contracts were cancelled, a total of 1,147 Dragonfly engines were produced; only twenty-three had been delivered by the end of 1918, but production continued into 1919.
  Fortunately, the Armistice prevented the introduction of the Dragonfly into the service. In view of the extent to which the Air Board had committed itself to the engine, a continuation of the war would have brought catastrophe when the Dragonfly was introduced in large numbers. It was brought to the stage where it would run reliably for two and a half hours, and one school of thought held the view that it would be worthwhile to replace each aeroplane’s engine after each patrol in view of the power it delivered.
  The failure of the A.B.C. Dragonfly led to the collapse of the Nighthawk production programme, for the aircraft had been ordered in large quantities before the engine’s shortcomings had been recognised as chronic. The Nighthawk went into limited service at home and in India, where No. 1 Squadron had a few in addition to its standard equipment of Snipes. The Nighthawk was occasionally fitted with the Bristol Jupiter engine in place of the erratic Dragonfly. Among experiments in which Nighthawks were used were those which were conducted with special crash-proof fuel tanks.
  The type was withdrawn as obsolete in the spring of 1923, whereafter enough airframes were kept in store to provide sufficient conversions to Nightjars to maintain twelve machines for two years. The Nightjar was a modification of the basic Nighthawk for use from aircraft carriers, and was one of a series of Nighthawk developments made by the Gloucestershire Aircraft Co., Ltd., which took over the Nieuport design in 1920. Several Nighthawk airframes were converted into the various Gloucester Mars types. Fifty of the versions which were alternatively known as Sparrowhawks were supplied to Japan in 1922.


SPECIFICATION
  Manufacturers: The Nieuport and General Aircraft Co., Ltd., Cricklewood, London, N.W. Other Contractors: The Gloucestershire Aircraft Co., Ltd., Cheltenham.
  Power: 320 h.p. A.B.C. Dragonfly I.
  Dimensions: Span: 28 ft. Length: 18 ft 6 in. Height: 9 ft 6 in. Chord: 5 ft 3 in. Gap: 4 ft 6 in. Span of tail: 9 ft. Airscrew diameter: 9 ft.
  Areas: Wings: 276 sq ft. Ailerons: each 9-3 sq ft, total 37-2 sq ft. Tailplane: 18 sq ft. Elevators: 10 sq ft. Fin: 5-2 sq ft. Rudder: 5-3 sq ft.
  Weights and Performance: No. of Trial Report: M.259. Date of Trial Report: July, 1919. Type of airscrew used on trial: A.B.8979. Weight empty: 1,500 lb. Military load: 218 lb. Pilot: 180 lb. Fuel and oil: 320 lb. Weight loaded: 2,218 lb. Maximum speed at ground level: 151 m.p.h.; at 6,500 ft: 140 m.p.h.; at 10,000 ft: 138-5 m.p.h.; at 15,000 ft: 134 m.p.h. Climb to 5,000 ft: 3 min; to 6,500 ft: 4 min 10 sec; to 10,000 ft: 7 min 10 sec; to 15,000 ft: 12 min 40 sec; to 20,000 ft: 20 min. Service ceiling: 24,500 ft. Endurance: 3 hours.
  Tankage: Petrol: 40 gallons. Oil: 4 gallons.
  Armament: Two fixed forward-firing Vickers machine-guns mounted on top of the fuselage and synchronised to fire through the revolving airscrew.
  Service Use: R.A.F. Squadrons, Nos. 1 and 8 (post-war).
  Serial Numbers: Between and about H.8533 and H.8544; between and about J.2405 and J.2416; between and about J.6925 and J.6930.
  Notes on Individual Machines: H.8544, J.2405, J.2416 and J.6926 became Mars VI; H.8539 and J.6930 became Nightjars (Mars X); J.6925 was a Nighthawk used by No. 1 Squadron.

Nieuport London

  ALTHOUGH the Nieuport London was not officially regarded as being in the same category as the Manchester, Bourges, Oxford and Cobham, it had several features in common with them. It was designed for two A.B.C. Dragonfly engines; the installation of two high-compression Siddeley Pumas was envisaged as a means of testing the airframe; but no example of the London was completed before the Armistice, and the aircraft did not fly until 1920.
  Whereas the other four Dragonfly-powered twins were designed as high-speed day bombers, however, the London was intended to be a night bomber; and particular attention had been paid to structural simplicity in order to achieve rapid production. The aircraft was designed in 1918 by H. P. Folland, and was an outstanding example of his genius, both structurally and aerodynamically.
  The London was a triplane of rather angular appearance. It was built of wood throughout, and the number of metal fittings was kept to a minimum: the structural members were of deal, pine and cypress; wooden pegs and dowels were used; joints were made in the simplest possible fashion, with nails and brass wire sewing; and the fuselage was covered with quarter-inch tongue-and-groove match-boarding. The wings and tail unit were fabric covered.
  All control surfaces were horn-balanced. Ailerons were fitted to all three mainplanes, but the London proved to be so responsive to the controls that the top and middle ailerons were removed and the wings suitably modified; the remaining bottom ailerons were quite adequate to provide lateral control. The tail-unit incorporated a keel-fin reminiscent of the S.E.5.
  The undercarriage consisted of two separate single-wheel units, one under each engine: the wheel track was therefore wide. The Dragonfly engines were mounted in carefully-faired nacelles which contrasted markedly with the London’s severe lines. With the A.B.C. radials the aircraft was officially named London Mark I; the designation London Mk. II was allotted to a Puma-powered version which had been designed to enable the airframe to be test-flown if Dragonflies were not available in time.
  It seems doubtful whether the London Mk. II was ever built. By the time an airframe was completed, Dragonflies were available, and H.1740 appeared with those engines.
  But by then the war was over, and new military aircraft were not wanted. It was proposed to convert the London into a transport aircraft with accommodation for thirteen passengers or 2,685 lb of mails or freight, but development of the design ceased when the Nieuport and General Aircraft Company closed down in August, 1920.


SPECIFICATION
  Manufacturers: The Nieuport and General Aircraft Co., Ltd., Cricklewood, London, N.W.
  Power: London Mk. I: two 320 h.p. A.B.C. Dragonfly I. London Mk. II: two 290 h.p. Siddeley Puma.
  Dimensions: Span: 59 ft 6 in. Length: 37 ft 6 in. Height: 17 ft 6 in. Chord: 6 ft 8 in. Gap: 5 ft 10 in. Stagger: nil. Span of tail: 20 ft 6 in.
  Areas: Wings: 1,100 sq ft. Ailerons: each 20 sq ft, total 120 sq ft. Tailplane: 64 sq ft. Elevators: 40 sq ft. Fin: 30 sq ft. Rudder: 20 sq ft.
  Performance: Maximum speed at ground level: 100 m.p.h. Climb to 10,000 ft: 30 min. Endurance: 4 hours. Tankage: Petrol: 175 gallons.
  Armament: A double-yoked pair of Lewis machine-guns could be carried on a Scarff ring-mounting on the front cockpit. The bomb load consisted of nine 250-lb bombs or their equivalent weight.
  Serial Number: H.1740.

Norman Thompson N.T.4 and N.T.4a

  IN March 1915, the Admiralty ordered fifty flying-boats of the type which became well known as the Curtiss H.4, or more popularly as the “America”. When fitted with satisfactory engines these Curtisses gave quite a good account of themselves and proved that flying-boats could be of use in warfare.
  On October 4th, 1915, the name of the White and Thompson company was changed to the Norman Thompson Flight Co., Ltd. The first aircraft to appear under the new name was a handsome twin-engined flying-boat of the same general type as the Curtiss H.4. Either because it was the fourth flying-boat design of the Bognor company or because it was desired to retain the numeral of the Curtiss type’s designation as indicative of a class of flying-boat, the new machine was designated N.T.4.
  Like the Curtiss H.4, the Norman Thompson N.T.4 was known in the R.N.A.S. as an “America” or, after the introduction of the Curtiss H.12, as a “Small America”. There was, however, no real connexion between the two flying-boats, and the N.T.4 differed from the Curtiss type in several major respects. It was larger, had four-bay wings and a different hull, and was driven by pusher engines instead of the tractors of the Curtiss H.4.
  The hull was a boat-built structure rather similar to the Curtiss hull but with finer lines. It had only one step, and the size and form of the hull fins recalled Curtiss practice, but a shallow and stubby forebody was used. Enclosed accommodation was provided for the crew, but the early form of cabin did not have as much glazing as would have seemed necessary; even the vertical windows had very wide framing to reduce the view further.
  The wings were of unequal span, but the extensions of the upper mainplanes were comparatively short; they were braced by cables, the landing wires running from king-posts above the outermost interplane struts. The ailerons of the first few N.T.4s projected behind the trailing edge of the upper wing, to which they were fitted.
  These first machines were powered by two 150 h.p. Hispano-Suiza engines installed as pushers and driving two-bladed airscrews. The engines were completely uncowled, and each had a large rectangular radiator mounted on the forward interplane struts. A small gravity fuel tank was mounted between the central struts, high up near the upper wing.
  The first N.T.4 of the first batch, No. 8338, was experimentally fitted with a two-pounder Davis gun. The gun was carried on a substantial horizontal mounting which was built above the cabin top. Supporting struts ran downwards through a cabin window on either side. The Davis gun was officially abandoned as a weapon, however, and never became standard armament for the N.T.4.
  N.T.4s of the second and all subsequent batches differed from the early machines in having more powerful engines. These were two of the 200 h.p. geared Hispano-Suizas, and with them the flying-boat was designated N.T.4a. The design of the cabin was successively modified to provide more transparency, and the final production version had all-over glazing of the cabin top. The gravity fuel tank was raised by placing it on top of the upper wing. For starting, fuel was pumped up to the gravity tank by hand, and once the N.T.4a was airborne the supply was maintained by two wind-driven pumps on top of the hull.
  In the later N.T.4a’s the ailerons were reduced in chord to bring their trailing edges flush with that of the upper mainplane; and the lower portion of the rudder was covered with plywood, for it was frequently awash. All the N.T.4s and N.T.4a’s were characterised by the same tail-unit, which incorporated a large low aspect-ratio fin and plain broad-chord rudder; the tailplane was mounted half-way up the fin, and was braced to the hull by struts.
  The Norman Thompson N.T.4a was quite widely used by the R.N.A.S. in home waters, presumably as a patrol machine and latterly as a trainer. It had quite a good performance, and probably would have made something of a name for itself if its appearance had not coincided so closely with the advent of the “Large America” types. Production continued into the summer of 1918, when it was hoped that the N.T.4a would be replaced by the Norman Thompson N.2C, a later design which incorporated N.T.4a flight organs.


SPECIFICATION
  Manufacturers: The Norman Thompson Flight Co., Ltd., Bognor Regis, Sussex.
  Power: Two 150 h.p. Hispano-Suiza; two 200 h.p. Hispano-Suiza.
  Dimensions: Span: upper 78 ft 7 in., lower 60 ft 10 in. Length: 41 ft 6 in. Height: 14 ft 10 in. Chord: 7 ft 6 in. Gap: 7 ft 6 in. Stagger: 8 1/2 in. Dihedral: 1° 30'. Incidence: 5°. Span of tail: 16 ft.
  Areas: Wings: upper 518 sq ft, lower 418 sq ft, total 936 sq ft. Ailerons: each 30-9 sq ft, total 61-8 sq ft. Tailplane: 75 sq ft. Elevators: 61-5 sq ft. Fin: 24 sq ft. Rudder: 31-9 sq ft.
  Weights and Performance (for 200 h.p. engines): Date of Trial Report: September 24th, 1917. Type of airscrews used on trial: D.1062. Weight empty: 4,572 lb. Military load: 273 lb. Crew: 540 lb. Fuel and oil: 1,084 lb. Loaded: 6,469 lb. Maximum speed at 2,000 ft: 95 m.p.h.; at 6,500 ft: 93 m.p.h.; at 10,000 ft: 91 m.p.h. Climb to 2,000 ft: 3 min 50 sec; to 6,500 ft: 15 min; to 10,000 ft: 31 min 5 sec. Service ceiling: 11,700 ft.
  Armament: Uncertain. Probably a Lewis machine-gun would be fitted on a bracket above the cabin, and bombs might be carried under the lower wings. An experimental installation of a two-pounder Davis recoilless gun was made in one N.T.4.
  Service Use: Used at R.N.A.S. Stations, Calshot, Cattewater, Dundee, Felixstowe, Killingholme, Invergordon, Scapa Flow.
  Production: Serial numbers were allotted for at least fifty N.T.4s and N.T.4a’s.
  Serial Numbers: 8338-8343. 9061-9064. N.2140-N.2159. N.2740-N.2759. 9061 was flown at Calshot.
  Costs:
   Airframe without engines, instruments or armament £3,610
   200 h.p. Hispano-Suiza engine (each) £1,004



Norman Thompson N.2C

  THE Norman Thompson N.2C was a 1918 development of the N.T.4a. It consisted of the wings and tail-unit of the N.T.4a fitted to a hull which was built on the Porte principle instead of being boat-built, and the type was intended to be a replacement for the N.T.4a. The Norman Thompson company had been contractors for hulls for F.2A flying-boats since the spring of 1917, and were therefore familiar with the system of construction.
  It was perhaps fortunate that the hull of the N.2C was such a simple structure, because F. P. H. Beadle had left the Norman Thompson company at the end of 1917. His experience had been a considerable asset to the company in the production of their earlier flying boats.
  Construction of two prototypes began in January 1918. The hull was basically a cross-braced girder structure, plywood-covered and generally similar to the hulls of the F-boats. The wings appeared to be standard N.T.4a surfaces. The rudder differed in shape from that of the N.T.4a, probably because the N.2C hull had a much shorter stern-post. Power was provided by two Sunbeam Arab engines driving four-bladed pusher airscrews.
  The Norman Thompson N.2C was intended for patrol duties and was equipped with wireless, guns and bombs. The prototypes were completed, but the type arrived too late to go into production or to see service.


SPECIFICATION
  Manufacturers: The Norman Thompson Flight Co., Ltd., Bognor Regis, Sussex.
  Power: Two 200 h.p. Sunbeam Arab.
  Dimensions: Span: upper 78 ft 7 in., lower 60 ft 10 in. Chord: 7 ft 6 in. Gap: 7 ft 6 in.
  Areas: Wings: 936 sq ft.
  Serial Numbers: N.82-N.83.

Norman Thompson N.1B

  EARLY in 1917 work began on the contruction of a small two-seat flying-boat which was intended to be a high-performance fighting machine. In the Norman Thompson works it was known as the T.N.T., or Tandem Norman Thompson, in view of its seating arrangement; as an aircraft it fell into the Admiralty category N.1B.
  The T.N.T. was a remarkably compact little machine in which considerable attention was paid to detail in order to reduce drag. The hull was a boat-built structure with two open cockpits in the deep forebody. The two-bay wings were unusual (on a flying-boat of that period) in two respects: they were of equal span, and ailerons were fitted to upper and lower wings. The ailerons were originally connected by light struts, but these were replaced by cables. Interplane bracing was by cables; the duplicated flying wires were carefully faired together. The wings were arranged to fold forwards, as on the A.D. Flying Boat.
  The fin and rudder assembly were quite different in appearance from any other Norman Thompson design, for they were of comparatively high aspect-ratio. The base of the rudder was plywood-covered.
  Power was provided by a 200 h.p. Hispano-Suiza engine which drove a four-bladed pusher airscrew. The trailing portion of the upper wing was cut away to allow the airscrew to revolve.
  The Norman Thompson N.1B was launched in September, 1917, and performed well. The machine underwent makers’ trials until the end of the year, when it was turned over to the R.N.A.S. at the Isle of Grain for Service trials. The Norman Thompson company were optimistic about the outcome, because they claimed to have achieved a speed of 108 m.p.h. and a climb of 20,000 feet in 18 1/5 minutes with the N.1B: these were quite prodigious performances for a flying-boat at that time.
  It seems doubtful that these results could have been obtained with a worthwhile load, for the official test figures fell a long way short of them. In particular, it was obvious that the machine could never have reached 20,000 feet on its official trial.
  The N.1B was not officially adopted, presumably because its performance did not represent much of an advance over existing types.


SPECIFICATION
  Manufacturers: The Norman Thompson Flight Co., Ltd., Bognor Regis, Sussex.
  Power: 200 h.p. Hispano-Suiza.
  Dimensions: Span: 34 ft 3 in. (folded, 13 ft 2 in.). Length: 26 ft 5 in. (folded, 32 ft 8 in.). Height: 9 ft 7 in.
  Areas: Wings: 357 sq ft.
  Weights and Performance: No. of Trial Report: N.M. 173. Date of Trial Report: May 18th, 1918. Weight empty: 1,895 lb. Military load: 20 lb. Crew: 360 lb. Fuel and oil: 398 lb. Loaded: 2,673 lb. Maximum speed at 2,000 ft: 93 m.p.h.; at 6,500 ft: 92 m.p.h.; at 10,000 ft: 86-5 m.p.h. Climb to 2,000 ft: 3 min 30 sec; to 6,500 ft: 14 min 20 sec; to 10,000 ft: 27 min 35 sec. Service ceiling: 12,600 ft. Endurance: 3 1/2 hours at 6,000 ft.
  Armament: Uncertain. Presumably one Lewis machine-gun fired by the observer.
  Serial Number: N.37.

Norman Thompson N.T.2B

  THE Norman Thompson Flight Company were contractors for the construction of the little F.B.A. trainer flying-boat, a frail-looking machine of French origin which nevertheless performed much useful work in training flying-boat pilots.
  For the same purpose the Bognor company produced a workmanlike and more substantial two-seat flying-boat which was obviously a descendant of the White and Thompson No. 3 Flying-boat. The new Norman Thompson machine was known as the N.T.2B, a designation which conflicted oddly with that of its immediate predecessor, the N.T.4. It seems probable, however, that the two-seater came within the Admiralty category N.2B, whence the numeral might have been derived.
  The hull was somewhat similar in general appearance to that of the White and Thompson No. 3, but had improved lines. It was a boat-built structure with a single step: over a framework of formers and stringers were applied two thicknesses of planking with a layer of oiled calico between them; the outer planking ran fore and aft. A neat enclosed cabin was provided for the instructor and his pupil, who sat side-by-side. Dual control was, of course, fitted.
  The two-bay wings were of unequal span: the extensions of the upper wings were braced from kingposts which were enclosed in fin surfaces of characteristic shape, situated above the outer pairs of interplane struts. Only the upper wings had ailerons, which projected behind the trailing edge of the mainplane.
  Abaft the wings the hull was little more than a boom to support the tail-unit. The vertical surfaces were very similar to those of the N.T.4, and the tailplane was set high on the fin. The bottom of the rudder was covered with plywood, and a beaching skid was fitted under the stern-post.
  Power was provided by a 160 h.p. Beardmore engine mounted between the wings and driving a four-bladed pusher airscrew. The engine was completely uncowled, and a tall rectangular radiator was mounted in front of the installation. The starting crank handle protruded through the radiator.
  The N.T.2B was accepted by the Admiralty and was ordered into production. It seems probable that most of the first fifty production machines had the Beardmore engine, though some are known to have had the 150 h.p. Hispano-Suiza. Late in 1917 it was decided to fit a more powerful unit.
  First choice fell on the 200 h.p. Sunbeam Arab, and it seems that the first installation was made in N.2294, an N.T.2B which had originally had a Beardmore. The more powerful engine brought with it some problems of longitudinal control. Its torque was greater than that of the Beardmore, and had to be overcome by mounting the engine slightly to starboard of centre.
  The N.T.2B proved to be a useful little flying-boat, so much so that R.N.A.S. demands for it exceeded the production capacity of the Norman Thompson works. Contracts were therefore given to S. E. Saunders and the Supermarine Aviation Works, and both firms built the N.T.2B under licence.
  In view of the Sunbeam Arab’s ill-starred career, it comes as no surprise to learn that the ultimate production version was powered by the 200 h.p. Hispano-Suiza engine. Again the problem of torque reaction arose, and ultimately a form of slewed engine mounting was evolved. This mounting was tested on N.2569 and proved to be satisfactory. The installation of the Hispano-Suiza was similar to that of the Sunbeam Arab, but could be distinguished by the starting crank handle running through the radiator: the Arab had no such frontal handle.
  The N.T.2B remained the standard flying-boat trainer until the Armistice. No further development of the design took place because of the absorption of the Norman Thompson company by Handley Page Ltd. The latter firm sent two N.T.2Bs (N.2284 and N.2293) to Peru to pioneer air transportation in 1919, but beyond that the type did not survive for long.


SPECIFICATION
  Manufacturers: The Norman Thompson Flight Co., Ltd., Bognor Regis, Sussex.
  Other Contractors: S. E. Saunders, Ltd., East Cowes, Isle of Wight; The Supermarine Aviation Works, Ltd., Woolston, Southampton.
  Power: 160 h.p. Beardmore; 200 h.p. Sunbeam Arab; 150 h.p. Hispano-Suiza; 200 h.p. Hispano-Suiza.
  Dimensions: Span: upper 48 ft 4 3/4 in., lower 27 ft 6 3/4 in. Length: 27 ft 4 1/2 in. Height: 10 ft 8 in. Chord: 5 ft 6 in. Gap: 5 ft 6 in. Stagger: nil. Dihedral: 1°. Incidence: 5°.
  Areas: Wings: 453 sq ft.
  Weights and Performance (with Sunbeam Arab engine): No. of Trial Report: N.M.211. Date of Trial Report: August 15th, 1918. Type of airscrew used on trial: D.1465. Weight empty: 2,321 lb. Military load: nil. Crew: 360 lb. Fuel and oil: 488 lb. Loaded: 3,169 lb. Maximum speed at 2,000 ft: 85 m.p.h.; at 6,500 ft: 83-5 m.p.h.; at 10,000 ft: 80-5 m.p.h. Climb to 2,000 ft: 4 min 10 sec; to 6,500 ft: 16 min 50 sec; to 10,000 ft: 33 min 40 sec. Service ceiling: 11,400 ft.
  Tankage: Petrol: 60 gallons. Oil: 8 gallons.
  Service Use: Used for training purposes at R.N.A.S. Stations Calshot, Lee-on-Solent, Felixstowe.
  Production and Allocation: Precise figures are not available, but it seems probable that over 150 Norman Thompson N.T.2Bs were built. On October 31st, 1918, the R.A.F. had seventy-nine on charge. Only twenty-three were at coastal stations; two were with contractors; three were at experimental units; the remaining fifty-one were in store.
  Serial Numbers: N.1180-N.1189: built by Norman Thompson. N.2260-N.2359: built by Norman Thompson. N.2400 and onwards, probably to N.2419 at least. N.2500-N.2523: built by Saunders. N.2555-N.2579: built by Norman Thompson. N.2760-N.2789: built by Supermarine. Notes on Individual Machines: N. 1189: R.N.A.S., Lee-on-Solent. N.2268: R.N.A.S., Lee-on-Solent. N.2284 and N.2293 went to Peru in 1919. N.2290: became G-EAQO. N.2555: R.N.A.S., Calshot (this N.T.2B had a 150 h.p. Hispano-Suiza engine). N.2561: R.N.A.S., Calshot. N.2569: first slewed engine installation.
  Costs:
   Airframe without engine and instruments £1,477 0s.
   Engines:
   160 h.p. Beardmore £1,045 0s.
   Sunbeam Arab £1,017 10s.
   200 h.p. Hispano-Suiza £1,004 0s.

Parnall Scout

  DURING the 1914-18 war, the wood-working firm of Parnall & Sons of Bristol built a considerable number of aeroplanes, particularly Avro 504s and Fairey Hamble Babies, for the Admiralty. The firm’s products were characterised by excellent workmanship and so favourably impressed the Admiralty that Parnalls were requested to undertake original design work.
  The first Parnall aeroplane was a large single-seat biplane of unusual appearance, variously known as the Parnall “Zeppelin Chaser” or “Night Flyer”, and powered by a 250 h.p. Sunbeam engine. It was designed by A. Camden Pratt and was built in 1916. The Parnall Scout was in fact designed specifically as an anti-Zeppelin aeroplane and, as befitted its nocturnal duties, it was painted all black.
  It was a two-bay biplane with wings of unequal span and chord, and the mainplanes were very heavily staggered. The upper wing was set low above the fuselage, presumably to give the pilot the best possible view upwards and forwards: his cockpit was situated immediately behind the trailing edge of the centresection. The fuselage was carried well above the lower wing, and the radiator was underslung.
  The Parnall Scout proved to be greatly overweight when completed, and it is doubtful whether it ever flew. It was sent to Upavon for its official tests, but calculations made there showed that the factor of safety was dangerously low and the aircraft was condemned.


SPECIFICATION
  Manufacturers: Parnall & Sons, Mivart Street, Eastville, Bristol.
  Power: 250 h.p. Sunbeam.
  Dimensions: Span: upper 44 ft, lower 40 ft. Chord: upper 7 ft, lower 5 ft 6 in. Gap: 5 ft 6 in. Stagger: 4 ft. Dihedral: 4. Incidence: 2. Span of tail: 18 ft.
  Areas: Wings: 516 sq ft. Ailerons: total 36 sq ft. Tailplane: 74 sq ft. Elevators: 38 sq ft. Fin: 6-5 sq ft. Rudder: 12-75 sq ft.
  Performance: Maximum speed at ground level: 113-5 m.p.h.; at 10,000 ft: 101-5 m.p.h.
  Tankage: Petrol: main tank 36 gallons.
  Serial Number: N.505, built under Contract No. C.P. 124455/16/24486.

Parnall N.2A, the Panther

  IN 1917, Parnall & Sons secured the services of Harold Bolas, who was released from the Air Department of the Admiralty for employment as the firm’s chief designer.
  Mr. Bolas had had considerable experience of aeronautical design work. He had started his aeronautical career in the drawing office of the Army Aircraft Factory at Farnborough, and had worked on the designs of some of the early Army airships. While with the Air Department he had had a share in the design of the A.D. Navyplane, which was built by the Supermarine Aviation Works in 1916. The Navyplane had a wooden monocoque nacelle which weighed only 85 lb, and in its design careful attention had been paid to the provision of good outlook for the crew.
  The first Bolas-designed Parnall aircraft was a two-seat biplane intended for Fleet reconnaissance and spotting duties, and came within the Admiralty category N.2A. The first prototype, N.91, appeared in 1917, and was followed by five others consecutively numbered up to N.96. By the time the sixth machine appeared, the type had been officially named Panther. The fourth prototype, N.94, was used for structural tests.
  The Panther was a small single-bay biplane of unusual appearance and design, powered by a 230 h.p. Bentley B.R.2 rotary motor. The fuselage was a wooden monocoque on a basic frame of four longerons which carried the plywood formers; the outer skin consisted of 1-6 mm birch plywood which was glued and screwed to the formers. The pilot and observer were accommodated in a high, elongated blister on top of the basic fuselage form; and the pilot had an excellent view, particularly for deck-landing, from his elevated position.
  Since the Panther was designed for use from ships and the early carrier vessels, it had to be made to fold in some way in order to conserve stowage space. An unusual expedient was adopted to achieve this end: the fuselage folded sideways to starboard at a point just behind the observer’s cockpit. A special channel was provided on the starboard side of the fuselage, and through it passed the control cables to the tail surfaces.
  The undercarriage was basically a plain vee structure, and was so on N.91 and N.92. A hydrovane was added in front of the wheels to prevent overturning in the event of ditching, and Grain flotation gear air bags were fitted to the top of each undercarriage vee. Other air bags were fitted inside the rear portion of the fuselage.
  The mainplanes had spindled spruce spars, and the ribs were of plywood capped with spruce. The ailerons were inset from the wing-tips which, if need be, could be detached for stowage. There was a large hole in the centre-section: this not only enabled the pilot to see vertically upwards but also provided him with the means of ingress into his cockpit.
  Entering the pilot’s cockpit of the Panther was something of a gymnastic feat. The trailing edge of the centre-section was hinged at the rear spar, and had to be lowered as the pilot’s first action in approaching his cockpit. He then climbed into the hole in the centre-section and lowered himself into his seat below.
  The tail-unit displayed further originality of thought, for the hinge-lines of both rudder and elevators were raked forward relative to the line of flight. Plain elevators were originally fitted to N.91 and N.92, but these had to be replaced by balanced surfaces of greater area in order to improve the handling characteristics at speeds near the stall.
  A production contract for 300 Panthers was given to the Parnall concern a few days before the Armistice. When the war ended the Air Ministry asked for the contract to be reduced to 150 machines. The Parnall company was owned by W. & T. Avery, Ltd., of Smethwick, who would not agree to this reduction, and the Air Ministry offered the revised contract to the British and Colonial Aeroplane Co.
  The offer was accepted with alacrity, and production was under way at Filton in 1919. During that year, fifty-one Panthers were delivered, and ninety-nine were completed in 1920. The original Parnall Company ceased to construct aeroplanes.
  The Panther was used by the Fleet Air Arm until 1924, when it was replaced by the Fairey HID. Two Panthers were supplied to America in 1920 and twelve to Japan in 1921-22. The Japanese machines were flown from the naval base at Yokosuka.
  Oleo undercarriages were later fitted to a number of Panthers, as were larger horn-balanced rudders. The latter modification was most probably made to improve rudder control at low speeds, lack of which was the machine’s only real fault; otherwise it was said to be delightful to fly and almost devoid of vices.


SPECIFICATION
  Manufacturers: Parnall & Sons, Mivart Street, Eastville, Bristol.
  Other Contractors: The British and Colonial Aeroplane Co., Ltd., Filton, Bristol.
  Power: 230 h.p. Bentley B.R.2.
  Dimensions: Span: 29 ft 6 in. Length: 24 ft 11 in. (folded, 14 ft 6 in.). Height: 10 ft 6 in. Chord: 6 ft 3 in. Gap: maximum 6 ft 3 in., minimum 6 ft 2 1/2 in. Span of tail: 12 ft. Airscrew diameter: 9 ft 1 1/4 in.
  Areas: Wings: 336 sq ft. Ailerons: each 11-3 sq ft, total 45-2 sq ft. Tailplane: 18-4 sq ft. Elevators: 19-3 sq ft. Fin: 6-85 sq ft. Rudder: 4-4 sq ft.
  Weights and Performance: No. of Trial Report: M.196. Date of Trial Report: May, 1918. Type of airscrew used on trial: Lang 4040. Weight empty: 1,328 lb. Military load: 366 lb. Crew: 360 lb. Fuel and oil: 541 lb. Weight loaded: 2,595 lb. Maximum speed at 6,500 ft: 108-5 m.p.h.; at 10,000 ft: 103 m.p.h. Climb to 2,000 ft: 2 min 20 sec; to 6,500 ft: 9 min 20 sec; to 10,000 ft: 17 min 5 sec. Service ceiling: 14,500 ft. Endurance: 45 hours at 10,000 ft.
  Tankage: Petrol: 58 gallons (48 gallons in the main tank under the pilot’s seat and 10 gallons in the upper centresection in two tanks, one either side of the cut-out). Oil: 10 gallons.
  Armament: One movable Lewis machine-gun on a pillar-mounting in the rear cockpit. On N.91 a fixed forward-firing Vickers machine-gun was mounted beside the pilot’s cockpit on the port side.
  Service Use: After the war, the Panther was used on the aircraft carriers H.M.S. Argus and H.M.S. Hermes. It was also flown from land stations at Leuchars (No. 406 Fleet Fighter Flight), Gosport (No. 421 Flight), and Port Grange.
  Production: Six prototypes and 150 production Panthers were built.
  Serial Numbers: N.91-N.96. N.7400-N.7549: built by British and Colonial Aeroplane Co., Ltd., under Contract No. 38A/988/C.1035.

Pemberton-Billing P.B.9

  THE name of Noel Pemberton-Billing has already appeared in this book as the planner of the raid on the Zeppelin sheds at Friedrichshafen, made on November 21st, 1914, by three Avro 504s of the R.N.A.S.
  Eleven years earlier, Pemberton-Billing had begun practical experiments in aeronautics. In 1903 he designed a man-lifting kite which was completed in the following year, and in 1905-6 he designed and made a valveless rotary petrol engine with a view to applying power to his kites. Until 1909 he experimented with several peculiar monoplanes which were only partially successful, and thereafter abandoned his aeronautical activities until September, 1913. He then began the design and construction of marine aircraft in the small factory he had taken over at Woolston.
  His designs all displayed startling originality of thought and application, and as evidence of his faith in the future of marine aircraft he coined the name “Supermarine” as his telegraphic address. The first aircraft to bear that name was the Supermarine P.B.1, a biplane flying boat which was displayed at the Olympia show in March, 1914. In June, 1914, the business became a limited company, known as Pemberton-Billing Ltd. Two months later Britain was at war.
  Such was Pemberton-Billing’s belief in the air and such the vitality of his thought that he immediately conceived the idea of a speedy single-seater for scouting purposes, which could be built quickly and easily in order to help provide the large number of aeroplanes that he believed would turn the war in the Allies’ favour at an early date.
  The new type was designated P.B.9, although it seems to have been Pemberton-Billing’s thirteenth design for a power-driven aircraft. From the commencement of design work until completion only eight days elapsed; of that period the construction occupied seven days. The P.B.9 was (for obvious reasons) nicknamed the “Seven-Day Bus”.
  It was a thoroughly conventional single-bay biplane, simple in construction and appearance. Typical of its simplicity was the shape of the engine cowling: this curved in one plane only, in conformity to the shape of the upper longerons as they curved downwards to the forward bearing for the 50 h.p. Gnome engine. The fuselage was wide enough to accommodate an 80 h.p. Gnome but none was available. The output of the rather old 50 h.p. Gnome was very nominal, yet the P.B.9 performed remarkably well with it.
  The interplane bracing was unusual, for there were no conventional centre-section struts. Their place was taken by full-length interplane struts placed close up against the fuselage sides. Each mainplane was made in one piece, and the spars of the lower wing ran under the fuselage. The attachment of the lower wing to the bottom longerons was of stark simplicity: four U-bolts were used, and by undoing them the wings could be instantly removed for replacement or transport.
  The P.B.9 was first flown in August, 1914, by Victor Mahl. The type was not adopted, but it was later bought by the Admiralty and was used for training purposes by the R.N.A.S. at Hendon.


SPECIFICATION
  Manufacturers: Pemberton-Billing, Ltd., Woolston, Southampton.
  Power: 50 h.p. Gnome.
  Dimensions: Span: 26 ft. Length: 20 ft. Chord: 4 ft 6 in. Gap: 4 ft 6 in. Stagger: nil. Dihedral: nil. Span of tail
8 ft 3 in. Wheel track: 4 ft 6 in. Airscrew diameter: 8 ft.
  Areas: Wings: 205 sq ft. Tailplane: 13 sq ft. Elevators: 11 sq ft. Rudder: 6 sq ft.
  Weights: Empty: 560 lb.
  Performance: Maximum speed: 78 m.p.h. Initial rate of climb: 500 ft per min. Endurance: 3 hours.
  Service Use: Used for training purposes by the R.N.A.S. at Hendon.

Pemberton-Billing P.B.23 “Push-Proj”, and P.B.25

  NOEL PEMBERTON-BILLING’S twenty-third design for an aeroplane was a clean little single-seat pusher biplane. It was, in fact, one of the earliest machines to be built to the single-seat pusher scout formula, for it was designed in 1915 and was contemporary with the D.H.2. The first machine appeared under the designation P.B.23, and was powered by an 80 h.p. Le Rhone engine.
  The P.B.23 was characterised by an unusually large gap between the mainplanes, which originally were quite straight in plan view. Ailerons were fitted to upper and lower wings, and were linked by light struts. The lower wings had a pronounced dihedral angle; the upper mainplane was quite flat. The nacelle was mounted mid-way between the wings; it was of good streamline form and was covered with light alloy sheet metal, a somewhat revolutionary constructional idea at a time when fabric and plywood covering was almost universal. The single Lewis gun was mounted in the extreme nose of the nacelle; it was low down relative to the pilot and must have been difficult to reach, even for reloading.
  The tail-booms were remarkable for the total absence of any cross-bracing or interconnecting struts save the short vertical struts which connected with the front spar of the tailplane. They were, however, stayed to the upper and lower ends of the forward interplane struts by cables from the rear spar of the tailplane. The tail-booms were substantial members, and in plan they diverged from the mainplanes to meet the long tailplane just inboard of the twin fins and rudders. The elevator lay between the vertical surfaces; the portions outboard of the fins were fixed surfaces only. There were cut-outs for the movement of the rudders.
  The long forward leg of each undercarriage vee was attached to the nacelle, and the short rear legs were attached to the ends of the front spar of the lower centre-section. The wheels, like the nacelle, were covered with metal. A tail-skid was attached to the bottom of each rudder.
  The original P.B.23 was flown at Hendon at the beginning of September, 1915. There the distinctive shape of the nacelle earned it the nickname of “Sparklet”, but it became more popularly known as the “Push-Proj”; the name signified pusher projectile.
  The P.B.23 was not adopted for Service use in its original form, but twenty machines of a modified type were ordered by the Admiralty. The modified version was officially known as the Pemberton-Billing Scout. The production machines differed in many ways from the prototype P.B.23. Pemberton-Billing regarded the production version as a new design, the P.B.25.
  The most obvious differences lay in the appearance of the nacelle and the sweep-back of the mainplanes. The nacelle was fabric-covered, faired out to an elliptical cross-section; and provision was made for the pilot’s gun to be mounted directly in front of his face, level with his eyes. A streamlined head-rest was also provided. The standard power unit of the production Scouts was the 100 h.p. Gnome Monosoupape, but 9001 was fitted with the 110 h.p. Clerget engine.
  The lower centre-section bracing consisted of N-struts, and the wide-track undercarriage was attached directly to the lower centre-section. Each wheel was on an independently-sprung half-axle, Sopwith fashion.
  The mainplanes were given a sharp sweep-back of 11 degrees, and inversely tapered ailerons were fitted. As on the P.B.23, landing and flying-wires consisted of duplicated cables faired together to reduce drag. The tail-unit and tail-booms were almost identical to those of the P.B.23, but the area of the fins was increased.
  With the Monosoupape engine the Pemberton-Billing Scout had quite a good performance, but it seems to have found no operational employment. It was probably used for experimental and training purposes, and at least one was at Eastchurch in 1916.


SPECIFICATION
  Manufacturers: Pemberton-Billing Ltd., Woolston, Southampton.
  Power: P.B.23: 80 h.p. Le Rhone. P.B.25: 100 h.p. Gnome Monosoupape; 110 h.p. Clerget.
Dimensions (production version): Span: 33 ft. Length: 24 ft 1 in. Height: 10 ft 5 in. Chord: upper 4 ft 8 1/4 in., lower 3 ft 10 1/2 in. Stagger: in. Dihedral: upper nil. Sweep-back: 11°. Span of tail: 16 ft 7 1/2 in.
  Areas: Wings: 277 sq ft.
  Weights: Empty: 1,080 lb. Loaded: 1,576 lb.
  Performance (with Monosoupape engine): Maximum speed: 99 m.p.h. Climb to 6,000 ft: 8 min 30 sec; to 15,300 ft: 40 min 30 sec. Endurance: 3 hours.
  Armament: One forward-firing Lewis machine-gun on top of nacelle immediately in front of the cockpit.
  Service Use: R.N.A.S. Stations at Eastchurch and Hendon.
  Production: Twenty Scouts of the P.B.25 type were ordered.
  Serial Numbers: 9001-9020. (9003 was flown at Eastchurch.)

Pemberton-Billing P.B.29

  PROOF of Noel Pemberton-Billing’s originality of outlook and his versatility as an aircraft designer was eloquently expressed in the P.B.29. He had strong opinions about the use of aircraft in warfare, and these he enunciated dramatically in his book Air War: How to Wage it, which was published in 1916.
  One of the defence problems peculiar to the 1914-18 war was that provided by enemy airships. These aircraft could approach their target in almost total silence and under cover of darkness, and in 1915 there was no organised, effective defence against them.
  In his book Pemberton-Billing defined his conception of an anti-airship aeroplane. The definition was almost completely realised in the later Night Hawk quadruplane, but the first attempt at a slow-flying night patrol aircraft was the Pemberton-Billing P.B.29.
  For his anti-airship machine Pemberton-Billing postulated a minimum flying speed of 35 m.p.h. in order to prolong cruising as much as possible, to increase the accuracy of gunfire, and to minimise the risks inseparable from night-flying at that time. To achieve this aim, the P.B.29 had quadruplane wings of very high aspect-ratio; and its makers claimed, possibly rightly, that it was the first quadruplane to fly successfully.
  The whole wing cellule was braced as a two-bay structure, with the engines mounted in the inner interplane struts and underslung from the second mainplane. The engines were two 90 h.p. Austro-Daimlers which were fitted with silencers; each drove a four-bladed pusher airscrew and had a rectangular frontal radiator. Ailerons were fitted to all four mainplanes. The fuselage was attached to the second wing. It had a short nose and there were two cockpits. The designer specified dual control and two pilots for his anti-airship patrol machine, so it seems reasonable to assume that the P.B.29 had dual control. Abaft the rear cockpit the fuselage was of triangular cross-section. A third crew-position was provided in the centre of the top wing, where a gun-mounting was installed. The gap between the top and third mainplanes was occupied by a streamline fairing to enclose the gunner’s body.
  The undercarriage was of very wide track. Under each engine nacelle there was a pair of wheels mounted on a horizontal skid which carried at its forward end a further pair of smaller wheels. The biplane tail unit incorporated three fins and three rudders.
  The P.B.29 was built with the same speed which had characterised the construction of the P.B.9, for it was completed only seven weeks after the beginning of design work. It was flown at Chingford, and was destroyed in a crash there.


SPECIFICATION
  Manufacturers: Pemberton-Billing, Ltd., Woolston, Southampton.
  Power: Two 90 h.p. Austro-Daimler.
  Armament: One gun, almost certainly a Lewis machine-gun, on movable mounting on cockpit in top wing.
  Service Use: Flown experimentally at the R.N.A.S. Station, Chingford.

Supermarine Night Hawk

  DURING its brief existence the Pemberton-Billing P.B.29 apparently created sufficient official interest for the Admiralty to order a development as an anti-airship patrol aircraft. In 1915 Flight-Lieutenant Pemberton-Billing was granted indefinite leave from the R.N.A.S. in order to design the machine, and again he produced a striking aeroplane which embodied several remarkably advanced features.
  Pemberton-Billing’s definition of an anti-airship aeroplane envisaged a machine with a maximum speed of at least 80 m.p.h. and a minimum speed of 35 m.p.h., the ability to climb to 10,000 feet in 20 minutes, a flight endurance of 12 hours, and equipment which included dual control and a searchlight.
  In the second Pemberton-Billing quadruplane, which was named Night Hawk, most of its designer’s ideas were translated into reality, and the aircraft was one of the most ambitious designs of the war. The swept-back wings had three bays of bracing, and inversely-tapered ailerons were fitted to all four mainplanes. The deep square fuselage filled the gap between the second and third wings.
  Enclosed accommodation was provided in an extensively glazed cabin amidships. The pilot sat behind the trailing edge of the third wing, and further glazed panels were provided in the fuselage sides to improve his downward view. Within the cabin, all wooden structural members were taped and clothed with fabric in order to minimise the risk of injury of crew members by splinters in the event of a crash.
  The cabin was surmounted by two upper gun positions which were level with the upper surface of the top wing. The forward position was that for the 1 1/2-pounder Davis gun which formed the Night Hawk’s offensive armament. This weapon was mounted on a special type of traversing mounting. The upper rear gun position was fitted with a Lewis gun on a Scarff ring-mounting: it was one of two such installations, which were intended purely to defend the Night Hawk against enemy attack; the second Lewis gun was carried on a Scarff mounting in the forward portion of the fuselage.
  The most remarkable feature of the Night Hawk was the small searchlight which was mounted in gimbals on the extreme nose of the fuselage; and in this respect the Night Hawk of 1915 concept was the true prototype of the many Allied aircraft which were successfully fitted with the Turbinlite and Leigh Light installations during the war of 1939-45. Power for the Night Hawk’s searchlight was provided by an inboard auxiliary power unit: a 5 h.p. A.B.C. flat twin engine mounted in the nose of the fuselage drove a generator. This was probably the first installation of an auxiliary power-unit in an aeroplane. The searchlight was controlled in elevation and azimuth by means of a Bowden cable operated by a lever within the fuselage.
  The primary use of the searchlight was to illuminate targets at night, but it could also have been used to select a suitable field for an emergency landing. As on the P.B.29, the undercarriage was of wide track to enhance ground stability for night landings.
  A ton of petrol was carried, and with engines throttled down the aircraft could remain airborne for over 18 hours. The fuel was carried in nine tanks which were fitted with interchange devices to enable any number or combination of tanks to be used or cut out in the event of damage by gunfire. All fuel leads and engine controls were carried in armoured casings.
  The designer was, even at that early date, alive to the dangers of crew fatigue, and a sleeping berth was provided to enable one man at a time to rest. It was justly claimed that the Night Hawk was the first aeroplane in the world to have this provision.
  The engines were two 100 h.p. Anzani ten-cylinder radials, driving opposite-handed four-bladed airscrews, and with them the Night Hawk was underpowered. Nor were the airscrews completely satisfactory, for they would not allow the engines to deliver their full r.p.m. Nevertheless the machine attained its specified speed of 75 m.p.h., and could be landed at 35 m.p.h. The test flying was done at Eastchurch by Clifford B. Prodger.
  In a brochure issued soon after the Armistice, the Supermarine company stated that no official reason was given for the abandonment of the Night Hawk. It seems probable, however, that the non-adoption of the big quadruplane was attributable to the successes achieved in the autumn of 1916 against enemy airships by standard types of Service machines armed with standard weapons.
  Noel Pemberton-Billing resigned his R.N.A.S. commission early in 1916 in order to stand for Parliament, for he wished to press for urgent reforms and improvements in the handling of Britain’s aeronautical affairs. On his election as member for East Herts on March roth, 1916, he sold his interests in Pemberton-Billing Ltd. in order to forestall any charges to the effect that he was making profit out of the war. Control of the company passed to Hubert Scott-Paine, and the new title of The Supermarine Aviation Works, Ltd., was adopted.
  These changes had taken place before the Night Hawk was completed, and it was for that reason that it was known as the Supermarine Night Hawk.


SPECIFICATION
  Manufacturers: The Supermarine Aviation Works, Ltd., Woolston, Southampton.
  Power: Two 100 h.p. Anzani.
  Dimensions: Span: 60 ft. Length: 37 ft. Height: 17 ft 8 1/2 in. Chord: 4 ft 2 1/2 in.
  Areas: Wings: 962 sq ft.
  Weights: Empty: 3,677 lb. Loaded: 6,146 lb.
  Performance: Maximum speed: 75 m.p.h. Endurance: normal 9 hours, maximum 18 hours.
  Armament: One 1 1/2-pounder Davis gun with 20 rounds of ammunition, carried on traversing mounting above top wing; one Lewis machine-gun on Scarff ring-mounting in nose of fuselage; one Lewis machine-gun on Scarff ring-mounting in elevated position just behind trailing edge of top wing. Six 97-round drums of ammunition were carried for the Lewis guns.
  Serial Numbers: 1388-1389. The second machine was not built.

Phoenix P.5, the Cork

  BY 1917, some considerable success had been achieved with British flying boats. Thanks to the superlative work of Squadron-Commander John Porte at Felixstowe, the practicability of large flying boats had been amply demonstrated. The tests of the A.D. flying boats built by Supermarine had proved the effectiveness and strength of the Linton Hope type of hull.
  In 1917, the Admiralty decided to build a large twin-engined flying boat of approximately the same displacement as a Porte boat, but fitted with a Linton Hope hull. This decision led to the design of the P.5 flying boat.
  The Linton Hope type of hull was totally different in construction from John Porte’s simple and sturdy “fuselage-type” hull. It was a kind of monocoque, and consisted of a keel or keelson which was continuous from stem to sternpost, and a large number of stringers attached to hoop-like formers spaced at intervals of 3 or 4 feet. Around the outside of the stringers ran numerous straps of wood, closely spaced; and to these the wooden planking was attached to form the outer shell. The resulting structure was remarkably strong, and could be made to have a good streamline form.
  The lines of the P.5 hull were set out by Lieutenant Commander Linton Hope, and two hulls were built to his principles by Messrs May, Harden and May. The completed hulls were then handed over to the Phoenix Dynamo Manufacturing Co. of Bradford for fitting out and attachment of wings, engines and tail-unit.
  The Phoenix concern had been Admiralty contractors for the construction of Short 184 seaplanes, Short bomber landplanes, Maurice Farman Longhorns with Rolls-Royce Hawk engines, and two Armstrong Whitworth F.K.10 quadruplanes; and were building F.3 and F.5 flying boats when the P.5 came along.
  The design of the wings, tail-unit and engine installation was undertaken by W. O. Manning of the Phoenix Dynamo Manufacturing Co., and the first prototype, N.86, emerged as a handsome biplane flying boat powered by two Rolls-Royce Eagle VIII engines. The hull was 45 feet in length, and weighed 1,230 lb. It was of good aerodynamic form, with an upswept lower line to ensure that the tail-unit remained clear of the water. The tailplane sat high on the fin, and was of inverted R.A.F. 15 section. It was made in two halves, joined down the centre line, and its incidence could be adjusted with the machine at rest. A horn-balanced rudder of characteristic shape was fitted.
  The mainplanes were of unequal span with two bracing bays outboard of the engines: the extensions of the upper wings were braced from faired rectangular king-posts above the outermost interplane struts. The upper wings had a marked dihedral angle, and they alone were fitted with ailerons. The wings had built-up wooden box spars and built-up wooden girder ribs. Compression struts were of steel tube, as were the interplane struts; the latter were faired. The spars of the lower centre-section ran through the hull of the first P.5, N.86, so that the lower wings were just below the top line of the hull.
  The engines were mounted between the wings: each rested on substantial wooden bearers which ran between the steel tube vee-struts which also served as interplane struts. Oblique steel tube struts braced the engine bearers to the wing roots. The engines were fed from two gravity tanks mounted below the upper centre-section. The two main tanks were carried within the hull in line with the wings, and fuel was pumped from them by means of two “Rotoplunge” pumps. The pumps were installed immediately above each main tank, and were driven by two small external windmills via chains and gearing; each pump could deliver 40 gallons per hour. A semi-rotary hand pump was provided for emergency use. The fuel system was arranged so that either engine or both could be supplied from either main tank.
  Dual controls were fitted in the two tandem cockpits immediately behind the bow gunner’s position. Wheel control was fitted for the operation of the ailerons, and the positions of the rudder bars were adjustable to accommodate pilots of varying leg lengths. Immediately behind the wings there were apertures in the hull for the waist guns.
  The performance of the P. 5 proved to be excellent, but the load water-line was high and consequently the mainplanes had been mounted too low down on the hull. This was remedied on N.87, the second prototype, which had the lower wing mounted wholly above the hull. The wing structure was otherwise unchanged, but two gunners’ nacelles were fitted to the trailing edge of the upper wing. These nacelles were installed in line with the first pair of interplane struts outboard of the engines, and were an interesting parallel to the experimental nacelles fitted to the upper wing of a Felixstowe F.2A. Whereas the gunners in the F.2A were above the wing leading edge, the P.5 gunners were primarily intended to defend the machine against attack from the rear.
  The area of the rudder on N.87 was increased above the tailplane: this modification resulted in a very ugly tail-unit.
  Proof of the P.5’s seaworthiness was provided when one of the prototypes was launched in stormy weather, flown in a 40-knot gale, and thereafter moored to a buoy for three days and nights. During that time the wind was continuously strong and gusting from 20 to 45 knots, and the P.5 was subjected to heavy rain, hail and snow. When brought ashore, the boat was found to have suffered no damage and had shipped no water.
  The P.5 appeared too late to go into production, and consequently was never adopted as a Service type. After the Armistice, ample quantities of F.5 flying boats were available to equip the squadrons, and no attempt was made to replace them until the Supermarine Southampton appeared. A ten-passenger commercial conversion of the P.5 was projected but was never made.
  The P.5s continued to be used for experimental purposes after the war, and N.86 was still being flown from the Isle of Grain and Felixstowe in 1924. The Phoenix concern became part of the English Electric Co., Ltd., and developed the Kingston flying boats from the basic P.5 design.


SPECIFICATION
  Manufacturers: The Phoenix Dynamo Manufacturing Co., Ltd., Bradford. Hulls made by May, Harden & May, Southampton Water.
  Power: Two 350 h.p. Rolls-Royce Eagle VIII.
  Dimensions: Span: upper 85 ft 6 in., lower 63 ft 6 in. Length: 49 ft 2 in. Height: 21 ft 2 in. Chord: 9 ft. Gap: maximum 10 ft 6 in., minimum 10 ft. Stagger: nil. Span of tail: 25 ft. Airscrew diameter: 10 ft.
  Areas: Wings: 1,273 sq ft. Ailerons: each 42-75 sq ft, total 85-5 sq ft. Tailplane: 143 sq ft. Elevators: 53 sq ft. Fin: 31 sq ft. Rudder: 42 sq ft.

Weights (lb) and Performance:
Flight condition Light load Normal load Overload
No. of Trial Report N.M.219 - -
Date of Trial Report August 31st, 1918 - -
Type of airscrew used on trial A.B.665 - -
Weight empty 7.437 - -
Military load 138 1,280
Crew 720 720 -
Fuel and oil 915 - -
Weight loaded 9.210 11,600 12,511
Maximum speed (m.p.h.) at
sea level - 106 -
1,000 ft - - 92
2,000 ft 105 - -
6,500 ft 101 - -
10,000 ft 98-5 94 -
m. s. m. s. m. s.
Climb to
1,000 ft - - - - 2 50
2,000 ft 2 35 - - - -
5,000 ft - - 10 00 - -
6,500 ft 10 50 - - - -
10,000 ft 18 35 30 00 - -
Service ceiling (feet) 15,100 - 6,400
Endurance (hours) - 8 -

  Tankage: Petrol: 360 gallons.
  Armament: One Lewis machine-gun on Scarff ring-mounting on bow cockpit; one Lewis gun at each waist position abaft the wings. The second P.5, N.87, could have a further four Lewis guns, two in each gunner’s nacelle above the top wing. The bomb load could consist of four 230-lb or two 520-lb bombs.
  Serial Numbers: N.86, N.87.

Port Victoria P.V.1

  AT the end of December, 1912, the first British seaplane station was commissioned at the Isle of Grain under the command of Lieutenant J. W. Seddon, R.N. By August, 1914, it had become one of the largest seaplane stations in the country.
  Even before the outbreak of war, it had been decided to use the Isle of Grain as something more than merely a seaplane base, and early in 1915 the R.N. Aeroplane Repair Depot was commissioned under Squadron Commander G. W. S. Aldwell. This unit was housed in what had once been a Salvation Army Congress Hall: the building was transported to the Isle of Grain and re-erected a few hundred yards away from the original Air Station. To distinguish the new unit from the original it was named Port Victoria.
  Later in 1915, the Experimental Armament Section was set up beside the Repair Depot, and early in the following year the Seaplane Test Flight came into being, originally in the person of one Flight Sub-Lieutenant who was under the orders of K Section of the Air Department of the Admiralty.
  As the war progressed, Port Victoria grew in size and the Isle of Grain air station declined. Ultimately the place became known as the Marine Experimental Aircraft Depot, and was divided into the Experimental Construction Depot, Seaplane Test Depot, and Experimental Armament Section.
  The Experimental Construction Depot was originally the R.N. Aeroplane Repair Depot. It began its construction work early in 1916.
  In the histories of the Sopwith Baby and the Fairey Hamble Baby mention is made of the malpractice of flying the Baby seaplanes in an overloaded condition. Early in 1916 it was not being done on a large scale, but even then Squadron Commander Seddon recognised that the Sopwith Baby was not capable of flying with two 65-lb bombs and other Service equipment.
  The Sopwith Baby’s wings had the flat, thin aerofoil section typical of so many contemporary aeroplanes, but tests had been carried out at the National Physical Laboratory with heavily cambered aerofoils which produced much greater lift than any then in use. Study of the reports of these tests convinced Squadron Commander Seddon that, by using wings of high-lift section, a seaplane of the Baby type could lift the requisite load at the expense of some speed. It was decided to experiment with a modified Sopwith Baby, and Port Victoria set about fitting a Baby with high-lift wings. The resulting seaplane was designated P.V.1. It consisted of the fuselage of a Sopwith Baby to which had been fitted a pair of wings of the same area as the original surfaces, but heavily cambered, of higher aspect-ratio, and with pronounced stagger. Enlarged floats were also fitted.
  So great was the haste to test the P.V.1 that no attempt was made to save weight in making the conversion. The original lower wing spars were simply sawn off flush with the fuselage sides and left in place; and the new mainplanes were fitted where they gave the pilot the best possible view. The centre of gravity was restored to its rightful place by the crude expedient of putting lead into the floats.
  It comes as no surprise, therefore, to learn that the completed P.V.1 was about 300 lb heavier than the standard Sopwith Baby. In spite of this weight penalty, however, the P.V.1 demonstrated the effectiveness of its high-lift wings by taking off with an additional 300 lb of lead on board and climbing to over 8,000 feet. The machine was reported to be free from “sogginess”.
  The maximum speed was no more than 67 knots (77 m.p.h.) but that was little worse than had been expected. In terms of climb, the P.V.1 fulfilled all that was expected of it.
  The machine remained at Port Victoria for some time, and was later used in the course of preliminary investigation of problems associated with the catapulting of aircraft. During the experiments the P.V.1 was once flown off a railway truck in the sidings at Grain.


SPECIFICATION
  Manufacturers: Conversion carried out at R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 100 h.p. Gnome Monosoupape.
  Areas: Wings: 240 sq ft.
  Weights: Loaded: 2,180 lb.
  Performance: Maximum speed: 77 m.p.h. Ceiling: over 8,000 ft.



Port Victoria P.V.2 and P.V.2bis

  THE results of the tests of the P.V.1 amply vindicated Squadron Commander Seddon’s belief in high-lift wings, but the idea of incorporating the results of the experiments in the design of a single-seat bomb-carrying seaplane was abandoned when the Fairey Hamble Baby was adopted in the expectation that it would fulfil Service requirements.
  Port Victoria’s next commission was to design a small fast seaplane for anti-Zeppelin duties. The specification centred upon the armament and its installation: a two-pounder Davis gun had to be mounted above the wings in such a position that it was clear of all wing bracing and yet accessible to the pilot for re-loading. Ten rounds of ammunition and fuel for three hours were to be carried; the machine had to have a maximum speed of 80 knots (about 92 m.p.h.), and had to be able to cruise at 10,000 feet. All this had to be achieved on a Gnome Monosoupape rotary engine of 100 h.p.
  Results obtained from the P.V. high-lift wing on the P.V.1 were sufficiently encouraging for Squadron Commander Seddon to suggest that a monoplane with a high-lift wing could satisfy the requirements of the specification. The aeroplane which was built under the designation P.V.2 was a sesquiplane, but the lower wing was of such small dimensions that the aircraft was nearly a monoplane.
  It was a remarkably clean little seaplane of distinctive appearance. The fuselage was basically a wire-braced wooden box girder, and was carefully faired to a circular cross-section throughout its length. The wing structure was noteworthy for its almost complete lack of bracing wires of any description. The upper wing was attached to the upper longerons of the fuselage, so that the pilot had an unobstructed view of the upper hemisphere and the Davis gun could be mounted in the manner required by the specification. The lower wing passed wholly under the fuselage, and the wing bracing consisted of a faired steel tube connecting the rear float attachment point to the main spar of the lower wing, whence a long vee-strut ran to both spars of the upper wing. Ailerons were fitted to the upper wing only, and at first ran along almost the entire length of the wing. The ailerons had a marked wash-out of incidence towards the tips.
  The floats were originally of the pontoon type, but Linton Hope floats were later fitted.
  The P.V.2 flew for the first time in June, 1916, and performed well, but its lateral control was not satisfactory. The trouble was traced to the excessive length and flexibility of the ailerons, and was eliminated by reducing these surfaces to half their original length and introducing additional stiffening.
  By the time the P.V.2 was completed the Davis gun had been abandoned. The aeroplane was considered to be such a promising design, however, that its development was continued.
  It was decided to convert the P.V.2 into a single-seat fighter seaplane by mounting two Lewis machine-guns on the upper wing. The initial tests had revealed that the upper wing obscured a critical part of the pilot’s field of view for alighting, so the machine was modified by raising the wing through one foot to a position level with the pilot’s eyes. A centre-section was fitted, and was of a length which left the angle of the interplane struts undisturbed; longer struts had to be fitted, owing to the increased gap. In its modified form the aircraft was re-designated P.V.2bis. Other work delayed the execution of the modifications, and it was not until early 1917 that the P.V.2bis was tested. It then proved to be very popular with all who flew it, and it provided data which were used in the design of later P. V. types.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 100 h.p. Gnome Monosoupape.
  Dimensions: Span: upper 27 ft on P.V.2; 29 ft on P.V.2bis; lower 19 ft. Length: 22 ft. Height: P.V.2, 8 ft 4 in.;
P.V.2bis, 9 ft 4 in. Chord: upper 5 ft 6 in., lower 2 ft 6 in. Gap: P.V.2, 3 ft 6 in.; P.V.2bis, 4 ft 6 in.
  Areas: Wings: P.V.2, 168 sq ft; P.V.2bis, 180 sq ft.

Weights {lb) and Performances:
Aircraft P.V.2 P.V.2bis
Date of Trial Report - March 29th, 1917
Weight empty 1,087 1,211
Military load 20 Nil
Pilot 180 180
Fuel and oil 303 311
Weight loaded 1,590 1,702
Maximum speed (m.p.h.) at
sea level 95-5 93
2,000 ft - 82
m. s. m. s.
Climb to
2,000 ft - - 3 50
3,000 ft 5 00 6 00
6,500 ft - - 16 05
10,000 ft - - 35 35
Service ceiling (feet) - 10,000

  Tankage: Petrol: 30 gallons. Oil: 9 gallons.
  Armament: P.V.2: it was intended to fit a two-pounder Davis gun above the fuselage; ten rounds of ammunition were to be carried. P.V.2bis: two Lewis machine-guns were to be mounted above the upper centre-section, firing forwards and upwards over the airscrew. Photographs show only one Lewis gun mounted to starboard of centre.
  Service Use: Flown experimentally at the Isle of Grain Test Depot.
  Serial Number: N.1.

Port Victoria P.V.4

  EARLY in 1916, the Experimental Armament Section asked Port Victoria to design a two-seat fighter.
  The chief requirement was that the design must enable the most effective possible use to be made of a gun.
  Preliminary drawings were prepared for a two-seat pusher landplane powered by a 110 h.p. Le Rhone rotary engine. The design seemed to hold promise, and was developed in some detail; presumably it was designated P.V.3. The machine was never built, however, for it was regarded so favourably that an official request was made for a seaplane of similar layout.
  This seaplane version was to carry wireless apparatus and a Lewis gun, and was to have a flight endurance of eight hours; the specified maximum speed was 80 knots (92 m.p.h.), and the climb to 5,000 feet was to be made in 15 minutes. It was promised that a new radial engine, the 150 h.p. Smith “Static” would be supplied: this engine weighed only 380 lb and was reputed to have remarkably low fuel and oil consumption.
  The initial calculations showed that, provided the engine gave its specified power, the required load could be carried and the performance achieved. Work was therefore begun on the seaplane, which was designated P.V.4. By the autumn of 1916 the airframe had been completed, but the promised engine was never delivered.
  For a two-seat seaplane, the P.V.4 was remarkably small and compact. It was a nacelle-and-tailbooms pusher biplane with wings of unequal span. The upper wings were attached to the upper longerons of the nacelle, as on the P.V.2. The monoplane tail-unit was conventional; and the fin and rudder combined to form an almost circular surface. The lower tailbooms converged to meet at the bottom of the rudder-post.
  The main floats of the undercarriage were of Linton Hope design, and the tail-float was similar to that of the P.V.2.
  The gunner occupied the forward cockpit, on which was mounted a Scarff ring. From his position above the level of the upper wing he had an excellent field of fire for his gun.
  When the non-appearance of the Smith engine held up the completion of the P.V.4, Wing Commander Aldwell made urgent representations to the Engine Section of the Air Department of the Admiralty. He obtained a promise that some engines would be delivered, but these materialised as a 150 h.p. Hispano-Suiza and a 190 h.p. Rolls-Royce Falcon, neither of which could be installed in the P.V.4. As a last resort, in the middle of 1917, the P.V.4 was assembled with a 110 h.p. Clerget rotary engine. The installation of this power-unit gave rise to a number of problems, for it was rather longer than the Smith radial, and it was found that the Clerget’s carburettor would come in the place occupied by the fuel tanks. By the time the necessary modifications had been made, the airscrew hub was nearly a foot further aft than the designed position.
  The Clerget installation brought the centre of gravity too far aft and, with the airscrew much nearer the tailplane than it should have been, it proved to be impossible to make the machine longitudinally stable both with the engine on and off. With the tailplane rigged to give correct balance with full power the machine became tail-heavy with the engine off, and all longitudinal control was lost when the airspeed dropped below 55 knots (63 m.p.h.). Each landing was therefore something of an adventure, and only the strength of its Linton Hope floats saved the P.V.4 from an untimely end.
  Redesign of the tail-unit could have remedied this fault, but the P.V.4 was no longer regarded as sufficiently important to justify the modifications. Machine-gun interrupter gears had meanwhile become available, but it is doubtful whether any other aeroplane of the 1914-18 war gave its observer a better field of fire than the P.V.4.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 110 h.p. Clerget. (Designed for 150 h.p. Smith Static.)
  Dimensions: Span: 32 ft.
  Areas: Wings: 220 sq ft.
  Weights: Loaded: 2,400 lb.
  Performance: Maximum speed: 70 knots (80-5 m.p.h.).
  Armament: One Lewis machine-gun on Scarff ring-mounting on front cockpit.
  Service Use: Flown experimentally at Isle of Grain Test Depot.
  Serial Number: N.8.

Port Victoria P.V.5 and P.V.5a

  WORK on the design of the P.V.4 had hardly begun when Port Victoria was asked by the Air Department of the Admiralty to design a single-seat seaplane for fighting and light bombing duties. The specification to which the machine was to be designed required a maximum speed of 85 knots (98 m.p.h.) at 6,500 feet with a load consisting of two 65-lb bombs (which were to be stowed within the fuselage), a machine-gun and ammunition, and fuel for four hours. The specified power-unit was the same 150 h.p. Smith Static radial as had been promised for the P.V.4.
  Once again the designers had to assume that the engine would be available and would give its specified performance. On these assumptions it was considered that the terms of the specification could be fulfilled, and two different seaplanes were designed and subsequently built. These aircraft were known as the P.V.5 and P.V.5a.
  The P.V.5 was clearly a development of the P.V.2, for it had the same sesquiplane layout: the wings were braced by struts to the undercarriage without the use of flying-wires, and a high-lift aerofoil section was employed.
  In order to provide comparative data, the P.V.5a was designed on more conventional lines. It was an equal-span single-bay biplane with cable bracing - the R.N.A.S. never standardised Rafwires for interplane bracing as did the R.F.C. - and a typical thin aerofoil section was used.
  Both machines had similar fuselages and tail-units, and both were designed with Linton Hope floats.
  Construction of the P.V.5 and P.V.5a was well advanced by the end of 1916 but, in common with the P.V.4, both were held up for lack of engines. In the history of the P.V.4 it has already been related how Wing-Commander G. W. S. Aldwell’s representations to the Air Department resulted in the delivery of a 150 h.p. Hispano-Suiza and a 190 h.p. Rolls-Royce Falcon, neither of which could be fitted to the P.V.4. The Hispano-Suiza was ultimately fitted to the P.V.5, however, and the machine was flown with it.
  In January, 1917, the Air Board was reorganised, and responsibility for the supply of all aircraft was transferred to the Ministry of Munitions. In due course, the Experimental Construction Depot at Port Victoria came under scrutiny and was near to being closed down, but eventually it was decided to complete the P.V.5 and abandon the P.V.5a.
  When completed, the P.V.5 emerged as a handsome single-bay biplane with a neatly faired fuselage and strut-braced tailplane. It was not fitted with the Linton Hope floats for which it was designed. They were replaced by special pontoon-type floats, each of which had an outwards slope on its bottom surface in order to provide the good shock absorption of a V-bottom float and yet keep the spray out of the airscrew. The floats performed their intended purpose very well, but suffered a number of misfortunes.
  As an aeroplane, the P.V.5 proved to be thoroughly satisfactory and won the praise of all its pilots. The view from the cockpit was excellent, manoeuvrability was good, and the machine was comfortable to fly. The performance did not come up to specification because an unsuitable airscrew was used during trials, and because the engine and its mounting were considerably heavier than the designed installation.
  Despite the earlier decision to abandon it, the P.V.5a was eventually completed, and was fitted with a 200 h.p. Hispano-Suiza engine. Linton Hope floats were fitted.
  The P.V.5a was quite a good aeroplane, and its performance was better than that of the P.V.5 and of the original specification, thanks to its more powerful motor. In terms of manoeuvrability and pilot’s view, the P.V.5a was inferior to the P.V.5 however, and the pity is that the P.V.5 was not also given the 200 h.p. Hispano-Suiza. However, by the time the two machines were tested it was decided that they were no longer needed for Service requirements, and development ceased.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: P.V.5: 150 h.p. Hispano-Suiza. P.V.5a: 200 h.p. Hispano-Suiza.
  Dimensions: P.V.5: Span: upper 32 ft, lower 21 ft. Length: 25 ft 6 in. Height: 9 ft 9 in. Chord: upper 6 ft, lower 3 ft 6 in. Gap: 4 ft. P.V.5a: Span: 33 ft 1 in. Length: 26 ft 9 in. Height: 13 ft 1 in. Chord: 5 ft. Gap: 5 ft.
  Areas: Wings: P.V.5, 245 sq ft; P.V.5a, 309 sq ft.
  Armament: Both aircraft had one fixed forward-firing Vickers machine-gun mounted on top of the fuselage and synchronised to fire through the revolving airscrew; P.V.5 could carry two 65-lb bombs inside the fuselage.
  Serial Numbers: P.V.5: N.53. P.V.5a: N.54.
Weights (lb) and Performance:
Aircraft P.V.5 P.V.5a
No. of Trial Report - N.M. 150
Date of Trial Report September 6th, 1917 April 22nd, 1918
Type of airscrew used on trial A.B.684 A.B.7282
Weight empty 1,788 1,972
Military load 192 112
Pilot 180 180
Fuel and oil 296 254
Weight loaded 2,456 2,518
Maximum speed (m.p.h.) at
2,000 ft 94-5 102-5
6,500 ft 94-5 102-5
10,000 ft - 100
m. s. m. s.
Climb to
2,000 ft 4 50 2 20
6,500 ft 20 15 9 00
10,000 ft - - 17 40
Service ceiling (feet) 9,900 13,700
Endurance (hours) - 2 1/2
Tankage (gallons): Petrol 36 41
Oil 4 5

Port Victoria P.V.7, the Grain Kitten, and P.V.8, the Eastchurch Kitten

  WHILE the P.V.5 and P.V.5a were under construction, an official request was made for the investigation of the possibility of building a small single-seat aeroplane of reasonable performance, powered by the 45 h.p. A.B.C. Gnat horizontally-opposed two-cylinder engine. The aim was to produce a machine which would be small enough to be carried by Torpedo-Boat Destroyers and similar small craft. Obviously, therefore, it had to be able to take off from a very small flying-off platform.
  Both the Experimental Construction Depot, Port Victoria, and the Experimental Flight at Eastchurch were asked to tackle this problem, and both ultimately produced designs. When the work began, the Experimental Flight was commanded by Squadron Commander H. R. Busteed, who had as his Chief Technical Officer Lieutenant G. H. Millar, R.N.V.R. Lieutenant Millar was the designer of the Eastchurch machine. When Squadron Commander Busteed took over the command of Port Victoria, Lieutenant Millar accompanied him, and the partly-built Eastchurch, machine was taken to Port Victoria for completion in the workshops there.
  The designation P.V.6 had been given to the design of a projected high-speed landplane scout which did not proceed beyond the preliminary layout. The little biplane designed by the Experimental Construction Depot was therefore designated P.V.7, and the Eastchurch machine was given the type number P.V.8 despite the fact that it was not a true P.V. design. Their diminutive size earned both machines the name Kitten, and for distinguishing purposes the P.V.7 was known as the Grain Kitten and the P.V.8 as the Eastchurch Kitten. Not unnaturally, the two Kittens differed markedly from each other. Like its predecessors, the Grain Kitten was a sesquiplane with wings of high-lift section and the characteristic elliptical vertical tail surfaces, but was otherwise of conventional appearance. The P.V.8, on the other hand, had rather severe lines with heavily staggered wings of equal span connected by a single broad interplane strut.
  Construction of the P.V.7 was entirely conventional - in fact, novel and unusual features were deliberately avoided in its design - and it was intended that the all-up weight should not exceed 520 lb. In point of fact the completed machine, fully loaded, weighed rather less than that.
  As with the P.V.4, P.V.5 and P.V.5a, so with the P.V.7 and P.V.8 the promised engines were not forthcoming. For want of the 45 h.p. geared Gnats each machine had to be considerably modified to take the 35 h.p. direct-drive Gnat instead. In both cases the engine had to be installed about six inches higher to bring the thrust line into its proper place. Both machines were completed in the summer of 1917.
  The Grain Kitten was completed first. On test, it proved to be tail-heavy, the performance did not come up to expectations, and it was very difficult to handle on the ground. Unfortunately, the original aerofoil section was by no means a success and ultimately new wings of more conventional form were fitted. At the same time the tail-unit was modified to overcome the tail-heaviness and the wheels were moved forward to improve ground-handling characteristics. Whether these attempted remedies proved effective is not known, because there is no record of any subsequent flights by the Grain Kitten.
  The P.V.8 design was based on a greater loaded weight than that of P.V.7, but larger wing area gave a lower wing-loading. The undercarriage had no springing: the large diameter tyres were relied upon to provide shock absorption. The lower ends of the main flying wires were anchored to the ends of the undercarriage axle, presumably to provide them with the most favourable angle possible. Ailerons were fitted to both wings, but only the upper mainplane was rigged with dihedral.
  As originally built, the P.V.8 had no fixed tailplane, but was provided with a balanced elevator similar to that which was a characteristic of the earlier Morane-Saulnier monoplanes and biplanes. On its first flight, however, the machine was found to be seriously unstable longitudinally. Most of the elevator balance area was removed, leaving only a small horn balance at the tip, and a small fixed tailplane was fitted. The effect of this modification was at once beneficial, and seemed to point to overbalancing of the original elevators as the cause of the instability.
  With its new tail unit, the Eastchurch Kitten proved to be remarkably successful. It was extremely easy to fly, and ultimately proved to be a much better aeroplane than the P.V.7 Grain Kitten.
  The P.V.8 became quite widely but erroneously known as the “Sopwith Kitten”, and was so described even in some official publications. The misnomer is usually attributed to the plank interplane struts, which resembled those of several types of Sopwith Triplane and the tapered-wing version of the Camel. Another possibility which cannot be completely disregarded is that the Sopwith company’s practice of naming most of their products after animals may have led to the belief that the Eastchurch Kitten was another addition to the Sopwith “Zoo”.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 35 h.p. A.B.C. Gnat.
  Dimensions: P.V.7: Span: upper 18 ft, lower 12 ft 7 in. Length: 14 ft 11 in. Height: 5 ft 3 in. Chord: upper 3ft 6 in., lower 2 ft 6 in. Gap: 3 ft. P.V.8: Span: 19ft. Length: 15 ft 7 1/2 in. Height: 5 ft 5 in. Chord: 3 ft. Gap: 3 ft.
  Areas: Wings: P.V.7, 85 sq ft; P.V.8, 106 sq ft.
  Armament: One Lewis machine-gun mounted above the centre-section.
  Serial Numbers: P.V.7: N.539. P.V.8: N.540.

  Weights (lb) and Performance:
Aircraft P.V.7 P.V.8
Date of Trial Report October 6th, 1917 October 11th, 1917
Type of airscrew used on trial Lang 2340 Lang 2340
Weight empty 284 340
Military load 30-5 30-5
Pilot 138-5 138-5
Fuel and oil 38 77
Weight loaded 491 586
Maximum speed (m.p.h.) at
2,000 ft 89 94-5
6,500 ft 85 87-5
10,000 ft 74 84
15,000 ft - 78
m. s. m. s.
Climb to
6,500 ft 10 50 11 00
10,000 ft 22 00 20 10
12,000 ft 35 00 - -
15,000 ft - - 47 00
Service ceiling (feet) 11,900 14,900
Tankage (gallons): Petrol 4 9
Oil 1 1

Port Victoria P.V.7, the Grain Kitten, and P.V.8, the Eastchurch Kitten

  WHILE the P.V.5 and P.V.5a were under construction, an official request was made for the investigation of the possibility of building a small single-seat aeroplane of reasonable performance, powered by the 45 h.p. A.B.C. Gnat horizontally-opposed two-cylinder engine. The aim was to produce a machine which would be small enough to be carried by Torpedo-Boat Destroyers and similar small craft. Obviously, therefore, it had to be able to take off from a very small flying-off platform.
  Both the Experimental Construction Depot, Port Victoria, and the Experimental Flight at Eastchurch were asked to tackle this problem, and both ultimately produced designs. When the work began, the Experimental Flight was commanded by Squadron Commander H. R. Busteed, who had as his Chief Technical Officer Lieutenant G. H. Millar, R.N.V.R. Lieutenant Millar was the designer of the Eastchurch machine. When Squadron Commander Busteed took over the command of Port Victoria, Lieutenant Millar accompanied him, and the partly-built Eastchurch, machine was taken to Port Victoria for completion in the workshops there.
  The designation P.V.6 had been given to the design of a projected high-speed landplane scout which did not proceed beyond the preliminary layout. The little biplane designed by the Experimental Construction Depot was therefore designated P.V.7, and the Eastchurch machine was given the type number P.V.8 despite the fact that it was not a true P.V. design. Their diminutive size earned both machines the name Kitten, and for distinguishing purposes the P.V.7 was known as the Grain Kitten and the P.V.8 as the Eastchurch Kitten. Not unnaturally, the two Kittens differed markedly from each other. Like its predecessors, the Grain Kitten was a sesquiplane with wings of high-lift section and the characteristic elliptical vertical tail surfaces, but was otherwise of conventional appearance. The P.V.8, on the other hand, had rather severe lines with heavily staggered wings of equal span connected by a single broad interplane strut.
  Construction of the P.V.7 was entirely conventional - in fact, novel and unusual features were deliberately avoided in its design - and it was intended that the all-up weight should not exceed 520 lb. In point of fact the completed machine, fully loaded, weighed rather less than that.
  As with the P.V.4, P.V.5 and P.V.5a, so with the P.V.7 and P.V.8 the promised engines were not forthcoming. For want of the 45 h.p. geared Gnats each machine had to be considerably modified to take the 35 h.p. direct-drive Gnat instead. In both cases the engine had to be installed about six inches higher to bring the thrust line into its proper place. Both machines were completed in the summer of 1917.
  The Grain Kitten was completed first. On test, it proved to be tail-heavy, the performance did not come up to expectations, and it was very difficult to handle on the ground. Unfortunately, the original aerofoil section was by no means a success and ultimately new wings of more conventional form were fitted. At the same time the tail-unit was modified to overcome the tail-heaviness and the wheels were moved forward to improve ground-handling characteristics. Whether these attempted remedies proved effective is not known, because there is no record of any subsequent flights by the Grain Kitten.
  The P.V.8 design was based on a greater loaded weight than that of P.V.7, but larger wing area gave a lower wing-loading. The undercarriage had no springing: the large diameter tyres were relied upon to provide shock absorption. The lower ends of the main flying wires were anchored to the ends of the undercarriage axle, presumably to provide them with the most favourable angle possible. Ailerons were fitted to both wings, but only the upper mainplane was rigged with dihedral.
  As originally built, the P.V.8 had no fixed tailplane, but was provided with a balanced elevator similar to that which was a characteristic of the earlier Morane-Saulnier monoplanes and biplanes. On its first flight, however, the machine was found to be seriously unstable longitudinally. Most of the elevator balance area was removed, leaving only a small horn balance at the tip, and a small fixed tailplane was fitted. The effect of this modification was at once beneficial, and seemed to point to overbalancing of the original elevators as the cause of the instability.
  With its new tail unit, the Eastchurch Kitten proved to be remarkably successful. It was extremely easy to fly, and ultimately proved to be a much better aeroplane than the P.V.7 Grain Kitten.
  The P.V.8 became quite widely but erroneously known as the “Sopwith Kitten”, and was so described even in some official publications. The misnomer is usually attributed to the plank interplane struts, which resembled those of several types of Sopwith Triplane and the tapered-wing version of the Camel. Another possibility which cannot be completely disregarded is that the Sopwith company’s practice of naming most of their products after animals may have led to the belief that the Eastchurch Kitten was another addition to the Sopwith “Zoo”.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 35 h.p. A.B.C. Gnat.
  Dimensions: P.V.7: Span: upper 18 ft, lower 12 ft 7 in. Length: 14 ft 11 in. Height: 5 ft 3 in. Chord: upper 3ft 6 in., lower 2 ft 6 in. Gap: 3 ft. P.V.8: Span: 19ft. Length: 15 ft 7 1/2 in. Height: 5 ft 5 in. Chord: 3 ft. Gap: 3 ft.
  Areas: Wings: P.V.7, 85 sq ft; P.V.8, 106 sq ft.
  Armament: One Lewis machine-gun mounted above the centre-section.
  Serial Numbers: P.V.7: N.539. P.V.8: N.540.

  Weights (lb) and Performance:
Aircraft P.V.7 P.V.8
Date of Trial Report October 6th, 1917 October 11th, 1917
Type of airscrew used on trial Lang 2340 Lang 2340
Weight empty 284 340
Military load 30-5 30-5
Pilot 138-5 138-5
Fuel and oil 38 77
Weight loaded 491 586
Maximum speed (m.p.h.) at
2,000 ft 89 94-5
6,500 ft 85 87-5
10,000 ft 74 84
15,000 ft - 78
m. s. m. s.
Climb to
6,500 ft 10 50 11 00
10,000 ft 22 00 20 10
12,000 ft 35 00 - -
15,000 ft - - 47 00
Service ceiling (feet) 11,900 14,900
Tankage (gallons): Petrol 4 9
Oil 1 1

Port Victoria P.V.9

  WHILE the Kittens were being built, Port Victoria was instructed to design a single-seat fighter seaplane in the same category as the P.V.2. It was stipulated that the new aircraft was to have the good handling qualities of the P.V.2, the same excellent outlook from the cockpit, and a really worthwhile maximum speed.
  In response to this request the design staff at Port Victoria brought out the design known as P.V.9, based on a 130 h.p. Clerget rotary engine. A high wing-loading was envisaged, and it was intended to use a high-lift aerofoil.
  Official prejudice against high-lift wings led to the rejection of the original design, and instructions were given that the R.A.F. 15 aerofoil was to be used. Port Victoria promptly objected on the grounds that, within the specified dimensions, use of R.A.F. 15 would mean a poorer rate of climb and a higher landing speed. These protests proved unavailing, and the aeroplane which was eventually built was considerably larger and heavier than the original concept.
  The P.V.9 bore a general resemblance to the P.V.2, for it was a sesquiplane braced entirely by faired steel tubes. The later machine had a vee-strut between each float and each lower mainplane. The fuselage was a clean, conventional structure which was mounted between the wings yet filled almost the whole gap; the proximity of the upper wing to the fuselage ensured a good all-round view for the pilot. The main fuel tanks were installed on each side of the fuselage within the fairings behind the engine cowling: the tanks were thus outside the basic fuselage structure, and a commodious cockpit was thereby provided in a small fuselage. A pair of Linton Hope floats were designed for the P.V.9 but were never built. The completed machine had pontoon-type floats, each with a single step, and a streamlined tail-float of circular cross-section.
  The P.V.9 made its first flight in December, 1917, powered by a 150 h.p. B.R.1 engine. Persistent and protracted engine trouble prevented the carrying out of flight trials until May, 1918; and even then truly representative performance figures could not be obtained because a suitable airscrew was not available. The machine was tested with one taken from a lighter and faster landplane (probably a Sopwith Camel), but it was by no means suitable for the P.V.9. It did not allow the engine to develop its full r.p.m. and caused a marked drop in r.p.m. above 2,000 ft. This had an adverse effect on speed and rate of climb, and reduced the ceiling by several thousands of feet.
  In spite of all the official interference and subsequent difficulties, the P.V.9 was reported to be the best single-seat seaplane fighter built up to the time of its trials. By then, however, the machine fulfilled no known Service requirement and was apparently shelved.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: 150 h.p. Bentley B.R.1.
  Dimensions: Span: upper 30 ft 11 in., lower 20 ft 1 in. Length: 25 ft 2 in. Height: 9 ft. Chord: upper 5 ft 6 in., lower 3 ft 9 in. Gap: 4 ft. Span of tail: 11 ft 6 in. Airscrew diameter: 9 ft.
  Areas: Wings: 227 sq ft.
  Weights and Performance: No. of Trial Report: N.M.178. Date of Trial Report: May 27th, 1918. Type of airscrew used on trial: A.B.644. Weight empty: 1,404 lb. Military load: 120 lb. Pilot: 180 lb. Fuel and oil: 261 lb. Loaded: 1,965 lb. Maximum speed at 2,000 ft: 110-5 m.p.h.; at 6,500 ft: 105 m.p.h.; at 10,000 ft: 99-5 m.p.h. Climb to 2,000 ft: 3 min 10 sec; to 6,500 ft: 13 min 20 sec; to 10,000 ft: 27 min 20 sec. Service ceiling: 11,500 ft. Endurance: 2 1/2 hours.
  Tankage: Petrol: 34-5 gallons. Oil: 6 gallons.
  Armament: One fixed forward-firing Vickers machine-gun mounted on top of the fuselage and synchronised to fire through the revolving airscrew; one Lewis machine-gun above the centre-section firing forwards and upwards over the airscrew.
  Serial Number: N.55.

Grain Griffin

  WHILE the P.V.9 was being constructed, a Sopwith B.1 single-seat bomber was delivered to Port Victoria. Instructions were issued that it was to be converted into a two-seat fleet reconnaissance machine, fitted with wireless and folding wings. The job was regarded as urgent, but in spite of that the Sopwith machine was delivered without a radiator and could not be flown for some time after its arrival at Grain.
  The Sopwith bomber was accompanied by its performance figures which, established at Martlesham Heath with a large load of bombs, were highly creditable. So good were the performance figures, in fact, that they gave rise to a good deal of conjecture as to why the aeroplane was not used for its designed purpose.
  The task of modifying the B.1 as required proved to be no easy matter. Its fuselage was comparatively slender and was not wide enough to accommodate the wireless installation, and the position of the outer interplane struts was such that they would foul the tailplane if the wings were folded. The Port Victoria design staff reported that it would be quicker and more satisfactory to design and build a new machine based on the Sopwith than to attempt to modify the original and produce a hybrid of doubtful value.
  Permission was granted for work on the new design, but the modification of the original machine was carried out at the same time.
  The modified aircraft was N.50. The pilot’s cockpit remained in its original position under the centresection, and a second cockpit for the observer was provided just behind the rear centre-section struts. The original narrow centre-section, borne on vertical struts, was retained; but the wing span had to be slightly reduced to enable the outer pair of interplane struts to clear the tailplane with the wings folded. The ailerons of N.50 were narrower than those of the original Sopwith B.1, and were hinged to an auxiliary spar some inches behind the rear spar. The engine was a 200 h.p. Hispano-Suiza; and a large hydrovane was fitted to the undercarriage forward of the wheels.
  These modifications were severely detrimental to the machine’s performance, and the ailerons proved to be virtually ineffective as control surfaces.
  By this time, design work was well advanced on the redesigned machine, which had been christened Griffin: six prototypes had been ordered. From the drawings for the new wings a set of mainplanes were made and fitted to the original fuselage. It is uncertain whether these wings included the wider centresection fitted to the Griffins proper, but the disposition of the bracing bays had been changed in such a way that the outer interplane struts cleared the tailplane when the wings were folded. The span was not reduced, however.
  The original universally-jointed control column was replaced by one with wheel control for the ailerons, and on test it was found that the machine had regained much of its lost performance.
  The true Griffins (that is, the machines built throughout to the revised design) had a wider fuselage and a considerably wider centre-section; consequently the span of the Griffin was 3 feet greater than that of the Sopwith B.1. In end elevation the centre-section struts were raked outwards, and the lower centre-section was braced by struts to the upper longerons of the fuselage.
  The first Griffin was N.100. This machine was powered by the 200 h.p. Sunbeam Arab, and had no hydrovane on the undercarriage. At first, plain ailerons were fitted, and were full-width surfaces hinged to the rear spar. Lateral control was still unsatisfactory, however, and horn-balanced ailerons were substituted: these cured the trouble. The engine installation also underwent detail modification at about this time.
  The original Sopwith-designed rudder was fitted to N.50 and, at first, to N.100. A horn-balanced surface of increased area was later introduced. The second true Griffin, N.101, was fitted with the 230 h.p. Bentley B.R.2 rotary engine in place of the Arab: the use of the alternative engine may have been prompted by trouble with the Arab.
  The Griffins were flown a good deal, but none saw operational service and the type was abandoned late in 1918. It was the last aeroplane to be produced by the Experimental Construction Depot.


SPECIFICATION
  Manufacturers: R.N.A.S. Experimental Construction Depot, Port Victoria, Isle of Grain.
  Power: N.50: 200 h.p. Hispano-Suiza. Grain Griffin: 200 h.p. Sunbeam Arab; 230 h.p. Bentley B.R.2.
  Dimensions: Span: 42 ft 6 in. Length: Arab, 27 ft 3 in.; B.R.2, 27 ft 6 in. Height: Arab, 10 ft 6 in.; B.R.2, 10 ft. Chord: 6 ft 3 in.
  Areas: Wings: 506 sq ft.
  Tankage: Petrol: 50 gallons. Oil: 5 gallons.
  Armament: One Lewis machine-gun on movable mounting behind rear cockpit.
  Serial Numbers: N.50; N.100-N.106.

  Weights (lb) and Performance:
Engine Arab B.R.2
No. of Trial Report N.M. 195 M.209
Date of Trial Report June 29th, 1918 June, 1918
Type of airscrew used on trial A.B.8212 Lang 4040
Weight empty 1,911 1,675
Military load 178 346
Grew 360 360
Fuel and oil 409 477
Weight loaded 2,858 2,858
Maximum speed (m.p.h.) at
5,000 ft 115 -
6,500 ft 113 112-5
10,000 ft 108-5 108
15,000 ft 101 99
m. s. m. s.
Climb to
6,500 ft 7 05 9 00
10,000 ft 12 00 15 55
15,000 ft 23 30 33 40
Service ceiling (feet) 19,000 16,500
Endurance (hours) 3 5 1/2

Porte Baby

  WHILE the experiments with the Curtiss America hulls were proceeding, Squadron Commander Porte used the experience gained from them to design a large three-engined flying boat. Construction was begun before the F.1 was tested, so the design of the large machine was based only on the results obtained from the four predecessors of the F.1. The new aircraft, No. 9800, was at once ironically dubbed Baby or H.M.S. Baby, on account of its great size.
  The precise origin of the Porte Baby is rendered somewhat obscure by the aircraft’s obvious relationship to another large three-engined boat which was described as a Curtiss in the 1917 edition of Jane’s All the World’s Aircraft. The so-called Curtiss had three pusher engines, and illustrations in the 1917 Jane’s were reproduced from photographs which appeared to have been made at Felixstowe. The big three-pusher flying boat and the Baby had so many common features that it is impossible to overlook the possibility that the “Curtiss” may in fact have been the Baby in its original form.
  However that may be, the Baby has always been depicted with its two outboard engines driving tractor airscrews whilst the central power unit alone was a pusher. The engines were three of the big Rolls-Royce vee-twelves of the type which was to become known as the Eagle, and delivered 250 h.p. each. The Baby’s plywood-covered hull was 56 feet 10 inches long, and incorporated an enclosed cabin for the pilots; there was one step under the centre of gravity. The wings were of unequal span, and were similarly disposed to those of the Curtiss America, with long extensions on the upper wing. All bracing was by stranded cables.
  On trial, it was found that the Porte Baby wallowed rather badly in a following sea, but this defect was overcome by lengthening the bows by three feet; the water performance was thereafter much improved. The machine was underpowered for its size, but the maximum speed of 78 m.p.h. was by no means bad in the circumstances.
  By this time, however, the results obtained from the Porte I hull had become available and had been utilised to produce the Porte II or F.2 flying boat, which was clearly so much superior to the Porte Baby that development of the three-engined machine was not pursued. Twenty production Babies were ordered from the Aircraft Manufacturing Company, however, construction being undertaken by that firm’s subsidiary company, May, Harden & May of Southampton Water. Only ten, numbered 9801-9810, were completed, but it seems that some at least of the other ten hulls were built.
  These production machines differed slightly from the prototype. No. 9800 had originally had a diamond-shaped structure of four struts at the rear of the outboard engines, but was later modified to have an improved engine installation in which a normal straight interplane strut was fitted between the rear spars of the upper and lower mainplanes in line with the engines. All production Babies incorporated this modification. Although it has been customary to regard the standard power plant of the Porte Baby as consisting of three Rolls-Royce engines, some at least (e.g., 9801) had a 260 h.p. Green as the central engine. Like the Rolls-Royce, the big Green was a water-cooled vee-twelve.
  The performance of the later production Babies benefited from the installation of three Rolls-Royce Eagles of later marks: at least one had three Eagle VIIIs. By the time No. 9810 appeared neater radiators, similar to those of the later F-boats, were fitted; and on this Baby the outboard engines drove two-bladed left-hand airscrews, whereas the corresponding power units on other machines drove opposite-handed four-bladed airscrews. The nose of No. 9810 was lengthened, and a bow cockpit was provided.
  The Porte Baby flying boats were used operationally from Felixstowe and Killingholme, and two were still on charge with the R.A.F. at the end of October, 1918. These big boats were vulnerable because of their low speed and lack of manoeuvrability. One of them was attacked by two enemy seaplanes and a landplane near the North Hinder Light Vessel shortly after 4 p.m. on October 1st, 1917, and a running fight was carried on for some twenty minutes. Normally, the operational crew of a Baby was five men, but on this occasion there were six on board; the pilots were Flight Commander N. Sholto Douglas and Flight-Lieutenant B. D. Hobbs. When the Baby was attacked, Hobbs was at the controls, and he skilfully avoided many of the enemy attacks. Ultimately the boat was forced down with its centre and port engines shot about, and while on the water it was machine-gunned by the enemy seaplanes.
  When the enemy machines had gone, the crew of the Baby managed to repair the damaged engines sufficiently to enable the boat to be taxied slowly towards the English coast, and by 1.30 a.m. on October and it reached Sizewell Gap, north of Orfordness. It was towed back to Felixstowe that morning. This experience led to the decision that the Porte Baby flying boats should not be used in areas where they might be attacked unless an escort of Curtiss H.12 or F.2A flying boats could be provided.
  The prototype Baby, No. 9800, was experimentally armed with a six-pounder Davis non-recoil gun, presumably for anti-submarine work, but there is no record that it was ever in action. A Baby (again almost certainly No. 9800) was also used in torpedo-carrying experiments: in April, 1916, it flew with two 14-inch torpedoes, one under each lower wing.
  In the history of the Bristol Scout it has already been related how, on May 17th, 1916, an aeroplane of that type was mounted on the upper wing of a Porte Baby, taken into the air by the flying boat, and launched at a height of 1,000 feet over Harwich. At that early date the Baby could only have been the prototype.


SPECIFICATION
  Manufacturers: Seaplane Experimental Station, Felixstowe.
  Contractors: The Aircraft Manufacturing Co., Ltd., Hendon, construction by May, Harden & May, Southampton Water.
  Power: Prototype: three 250 h.p. Rolls-Royce. Production: some had two 250 h.p. Rolls-Royce and one 260 h.p. Green; ultimately three 325 h.p. Rolls-Royce Eagle VIIs or 360 h.p. Eagle VIIIs were fitted.
  Dimensions: Span: 124 ft. Length: 63 ft. Length of hull only: 56 ft 10 in. Height: 25 ft. Beam at step: 14 ft.
  Areas: Wings: 2,364 sq ft.
  Weights: Production machine: Empty: 14,700 lb. Military load: 298 lb. Crew: 1,120 lb. Fuel and oil: 2,482 lb. Weight loaded: 18,600 lb.
  Performance: Prototype: maximum speed: 78 m.p.h. Climb to 3,000 ft: 20 min. Production - Eagle VIII engines (from Trial Report No. N.M.129, dated March 12th, 1918): maximum speed at sea level: 92 m.p.h.; at 2,000 ft: 87-5 m.p.h.; at 6,500 ft: 72 m.p.h. Climb to 2,000 ft: 5 min 20 sec; to 6,500 ft: 25 min 05 sec. Service ceiling: 8,000 ft.
  Armament: Machine-guns were carried, presumably on mountings in the hatchway immediately behind the pilots’ cockpit, and probably behind the wings. The prototype had a six-pounder Davis gun mounted on the bows, and was also used in torpedo-carrying experiments.
  Service Use: R.N.A.S. Stations at Felixstowe and Killingholme.
  Production and Allocation: The prototype and ten production Babies were built; some additional hulls may also have been made. Two Babies were still on charge with the R.A.F. on October 31st, 1918.
  Serial Numbers: 9800-9820. Only 9800-9810 were delivered complete.
  Notes on Individual Machines: 9800: officially accepted at Felixstowe, November 2nd, 1916. 9801: officially accepted on March 27th, 1917; written off at Killingholme January 9th, 1918. 9802: officially accepted at Felixstowe on July 16th, 1917. 9805-9809 were officially accepted at Killingholme. 9806 was in store on September 12th, 1918; 9807 was at a Fleet Base on October 14th, 1918. 9808 and 9809 were in store in September, 1918.

B.E.1

  IN January, 1911, the first aeroplane designed throughout at the Balloon Factory was built by ostensibly reconstructing a crashed Bleriot monoplane: the result of the “reconstruction” was the S.E.1. It was only by recourse to such devices that the staff at Farnborough could construct aeroplanes of their own design, for the Factory had neither funds nor authority for the construction of aircraft.
  A similar opportunity presented itself in April, 1911, when a Voisin pusher biplane with a 60 h.p. Wolseley engine was sent to Farnborough for repair: it had originally been presented to the War Office by the Duke of Westminster. The opportunity was taken to build a two-seat tractor biplane to the designs of F. M. Green and Geoffrey de Havilland.
  The aircraft which emerged was the first to fall into the B.E. category and was consequently named B.E.1. At first the B.E.1 had the same Wolseley engine which had been installed in the Voisin. A rather sketchy cowling was fitted to the engine, and a large rectangular radiator was mounted between the forward centre-section struts. Soon, however, the Wolseley was replaced by a 60 h.p. Renault, and the last link with the Voisin machine was severed. These vee-eight engines were so quiet in comparison with the contemporary rotaries that the B.E.1 was known as the Silent Aeroplane.
  The B.E.1 showed much advanced aerodynamic and structural thinking. The fuselage was a cross-braced wooden box-girder, fabric covered and with a rounded top-decking behind the long undivided cockpit. The ear-shaped rudder was mounted on the extended sternpost; there was no fin. The wings were of unequal span, and warping was used for lateral control. Fuel was carried in a gravity tank slung under the centre-section.
  For three years the B.E.1 gave valuable and varied service, and participated in many experiments. In the course of these it suffered many mishaps and underwent many repairs. Its undercarriage bore the brunt of most of the crashes and had to be replaced frequently.
  Apart from the testing of several experimental devices, the B.E.1 was the vehicle used for testing one of the earliest installations of wireless equipment in an aeroplane. Captain H. P. T. Lefroy, R.E., who in October, 1909, had been given charge of all experimental work in wireless telegraphy for the Army, devoted a good deal of time in the summer of 1911 to collaborating with R. Widdington in the design of a transmitter for use in aeroplanes. When completed, the transmitter was installed in the B.E.1 and tested in the air by Captain Lefroy; Geoffrey de Havilland flew the aircraft on this occasion.
  In March, 1912, the B.E.1 was handed over to the Air Battalion and was assigned to Captain C. J. Burke. When the Royal Flying Corps was formed a few weeks later the machine was part of the equipment of No. 2 Squadron of which Major Burke became the Commanding Officer. The B.E.1 later received the official serial number 201, and was well-known to the officers of the infant R.F.C., officers whose names were to become part of the tradition of the new service: Brancker, Brooke-Popham, Longcroft, Sykes, Ashmore.
  A distinction which can be claimed for the B.E.1 is that it was the first British aeroplane in respect of which a document roughly equivalent to a certificate of airworthiness was issued. This was dated March 14th, 1912.
  In May, 1912, Captain Lefroy installed a generator in the B.E.1; it was driven from the engine crankshaft by a length of bicycle-chain running on sprockets.
  The B.E.1 continued to be used at Farnborough and Netheravon until it was finally written off in a crash in January, 1915. Its epitaph was written several years later by Sir Walter Raleigh in Vol. I of The War in the Air: “The first machine of its type, it outlived generations of its successors, and before it yielded to fate had become the revered grandfather of the whole brood of Factory aeroplanes”.


SPECIFICATION
  Manufacturers: The Royal Aircraft Factory, Farnborough, Hants.
  Power: 60 h.p. Wolseley; 60 h.p. Renault.
  Performance: Maximum speed: 59 m.p.h. Climb to 600 ft: 3 min 54 sec.
  Service Use: Flown by the Air Battalion, R.E., and later by No. 2 Squadron, R.F.C., at Farnborough; later flown at Netheravon.
  Serial Number: 201.

B.E.2, 2a and 2b

  THE first B.E.2 appeared early in 1912. There was little to distinguish it from the B.E.1, for the differences lay in details only. Indeed, it is possible that the designation signified that the particular aircraft was the second aeroplane in the B.E. category rather than that it was a distinct and separate type from the B.E.1. Similar considerations probably applied in the cases of the aeroplanes which became known as the B.E.3, 4, 5, 6 and 7, and what may have been merely sequence numbers came to be used as type numbers. However that may be, the design of B.E. No. 2 became standardised as the B.E.2, and the type was produced in small numbers.
  The B.E.2 was powered by the more powerful 70 h.p. Renault engine, but the basic airframe was similar to that of the B.E.1. The fuselage was unchanged, but the top-decking behind the cockpit was shortened by one bay and the fairleads for the rudder cables were brought forward a corresponding distance.
  The tailplane and elevators of the B.E.2 were of greater area, and the mainplanes were rigged with a small dihedral angle; the upper wing was of slightly greater span than the lower. The undercarriage was again of the twin-skid type, but the skids were shorter and radius rods were fitted to prevent longitudinal movement of the axle.
  Some of the earliest B.E.2s were produced by “rebuilding” other crashed aeroplanes, and at first there was no real standardisation. The 70 h.p. Renault was the engine normally fitted, but B.E.2 No. 205 had a 60 h.p. E.N.V. at one time. The later B.E.2s had wings of equal span, and separate cockpits were provided for the crew by the addition of a short length of decking between the seats. A gravity fuel tank was mounted under the centre-section. The observer, who occupied the front seat, was almost completely exposed, for there was no cowling or decking behind the engine.
  The usual wooden construction was used throughout, apart from the outlines of the elevators and the complete rudder, which were made of steel tubing.
  In May, 1912, King George V visited Farnborough and inspected the Military Wing of the R.F.C.: on this occasion B.E. machines were flown before the King. On August 12th of that year, Geoffrey de Havilland broke the British altitude record by flying a B.E.2 to 10,560 feet with Major F. H. Sykes as passenger. The B.E. reached that height in about 45 minutes.
  This flight alone was convincing evidence of the machine’s quality, but a few days later it was put through some of the official tests which constituted the 1912 Military Trials. The Trials were intended to select the aeroplane best suited to the requirements of the R.F.C., and were on competitive lines. They were flown off at Salisbury Plain.
  The B.E.2 was flown hors contours by Geoffrey de Havilland: having been built at the Royal Aircraft Factory it was not eligible to compete in the Trials. Its performance in these trials showed that it was the best all-round machine there; better in all important respects than the Cody biplane which was declared the winner of the competition, but which owed its success to its 120 h.p. Austro-Daimler engine and not to any excellence of design.
  The B.E.2 was built in some numbers for the equipment of the R.F.C. Only a handful were made at the Royal Aircraft Factory itself, and the majority were made by Handley Page, Ltd., Hewlett and Blondeau, Ltd., and Vickers, Ltd.
  Late in 1912 the B.E.2a appeared. This variant had a revised fuel system, and decking was fitted behind the engine: it enclosed the tank which was installed there and gave the observer some protection from the elements and the regurgitations of the Renault. There