C.Barnes Bristol Aircraft since 1910 (Putnam)

The Bristol-Coanda Monoplanes

   Henri Coanda, son of Gen. Coanda the Rumanian War Minister, had trained as an engineer in France and was an artist of merit as well. He. Had studied under Eiffel, whose wind-tunnel at Auteuil was the first to be built in Europe. At the Paris Salon of 1910, Coanda exhibited a novel biplane whose engine drove, not an airscrew, but a small-diameter ducted fan. It is uncertain whether this biplane ever flew, as has been claimed, but Coanda deserves due credit for originating this form of propulsion unit. Another of Coanda's projects was a tandem-wing monoplane with a submerged engine driving an airscrew mounted half-way along a streamlined circular-section fuselage.
   Coanda joined the Company's staff in January 1912, and his first product at Filton was an orthodox tandem two-seater monoplane (No. 77), derived from the Prier-Dickson. The wings were structurally Similar to Prier's, having two tubular steel spars filled with wood, on to which the ribs were threaded and located by clips so that they were free to rotate round the spars for warping. In Prier's design the front spars were always longer, than the rear, giving a forward rake to the tip, but this somewhat restricted the range of warping movement available. Coanda's wings had their tips raked the opposite way, with the rear spar longer than the front, which resulted in a longer flexible trailing edge. The wings were braced above and below to steel tube pylons, the control pulleys being enclosed in streamline fairings at the apex of each pylon. The 50 h.p. Gnome engine was surrounded by a circular cowling, which prevented oil from being thrown back to the cockpits. The undercarriage had steel-tube skids of the type originated by Grandseigne, and the cockpits were furnished with wicker seats and had non-inflammable celluloid windows in the fuselage sides. No. 77 was sent to Larkhill on 27 March 1912 and remained there for testing for some weeks. A second monoplane, No. 80, was similar but had side-by-side seats with dual controls. It was built in May 1912 and remained in continuous use as a school machine at Brooklands and Larkhill until crashed by Merriam and Gipps on 26 January 1914. Both these models were offered as suitable for training purposes and eventually five more of the tandem version and six more of the side-by-side version were built, all with 50 h.p. Gnomes, during 1913. Of the tandem version, No. 132 went to Italy and Nos. 185, 186, 188 and 189 to Rumania; and of the side-by-side version, Nos. 110 and 165 went to Italy and Nos. 164, 166 and 176 to Rumania, while the last, No. 177, was retained at Larkhill and was finally converted into the one and only side-by-side Coanda biplane No. 218.
   On 15 May 1912 the War Office announced conditions for the Military Aeroplane Competition, and it was found that the competing aircraft had to be designed and built by 15 July! It was, of course, impossible to produce a new design specially to meet the conditions in only two months, and in any case the prize money, limited to ?5,000 to anyone entrant, hardly justified an all-out effort of this kind. However, Coanda had already made good progress with a new design for a military monoplane and two of these were entered, together with the two G.E.2 biplanes, in the competition. The rules laid great emphasis on suitability for reconnaissance and ease of maintenance and transport. Dual controls were required, together with a good view downwards and good stability, and the pilot was expected to start his engine and operate from unprepared fields without assistance. The aircraft had to be tendered at Larkhill packed in a rail transport crate not longer than 32 ft. and had to be capable of being towed on its own wheels or trolley in an army column. The flying tests were stringent and included duration, speed, altitude and climb minima, together with landing on various surfaces and quick take-off from a harrowed field. At least one flight had to be made in a wind averaging 25m.p.h. Coanda's two competition monoplanes, Nos. 105 and 106, were both equipped with the new 80 h.p. Gnome engine. Great attention had been paid to drag reduction and the usual pyramids of cabane struts were replaced by a pair of vertical steel pylons on the fuselage centre-line carefully faired with wood. The passenger's cockpit was between these pylons and the pilot's just behind, so that from a distance the machine appeared to have a crew of four. The wings were of the same type as on No. 77 and their cables had quick release clips for easy dismantling. The cockpit sides had celluloid windows and the trailing edges were cut back at the wing roots to improve the pilot's view. Like all Coanda monoplanes they had a semicircular fixed tailplane and a one-piece elevator, with a balanced rudder above. Busteed experienced directional instability on No. 105 with the original rudder, and a smaller Prier-type rudder was tried in conjunction with a fixed fin, but this was no better and the trouble was finally cured by a balanced rudder of revised outline. Nos. 105 and 106 (competition numbers 14 and 15) were flown by Busteed and Valentine, respectively. Valentine, attempting the duration test of3 hours in 15 had engine failure while approaching a flock of sheep and struck a fence in attempting to avoid them. The damage was soon repaired, but Valentine withdrew from the trials and Pixton was allowed to take his place.
   Both Busteed and Pixton did well in the ensuring tests and eventually shared third place with the British Deperdussin in the final assessment and were awarded ?500 each. Pixton excelled in the rough weather test, with Capt. Patrick Hamilton, R.F.C., as passenger, when he took-off and remained up for over 15 min. in violent gusts whose recorded speed varied from 17 to 44 m.p.h. Pixton also headed the list in the range test with 420 miles, while Busteed was third in the high speed test with 73 m.p.h., only 2 m.p.h. less than the best. Neither succeeded in taking-off from a harrowed field and Coanda quickly appreciated that the wing-loading was somewhat too high; all subsequent monoplanes of the type had larger wings and the details were carefully redesigned to save weight. These improvements cou1d have been made before the competition began, had more time been available. Both Nos. 105 and 106 were bought by the War Office and received military serials 263 and 262 respectively. Training was begun on them in preparation for the autumn manoeuvres, and on 10 September Edward Hotchkiss, by then a second-Lt. in the Special Reserve, with Lt. C. A. Bettington, R.F.C., as passenger left Larkhill to fly to Hardwick, near Cambndge, on 263. They intended to land at the Port Meadow, Oxford, and while gliding down from 2,000 ft. above Wolvercote Hotchkiss lost control; the descent became a steep dive and the starboard wing fabric tore off, both men being killed instantly. It appeared that the quick-release clip of one of the flying wires had become detached, but, as this was not the first of several similar accidents, the War Office somewhat summarily banned the flying of all monoplanes by pilots of the Military Wing, R.F.C.; no such ban was imposed on Naval pilots by the Admiralty and indeed the War Office ban was lifted five months later, but it ended the Company's hopes of supplying Coanda monoplanes in quantity to the Royal Flying Corps. Foreign interest in the design remained, however, and enquiries were received from Italy and Rumania for the improved model with span increased from 40 ft. to 42 ft. 9 m., which became standardised for production.
   A single experimental variant, which was not a success, emerged in September 1912 alongside the first of the production batch. This was No. 111, nicknamed The Elephant. It was intended to compete with the strongly built Etrich and D.F.W. monoplanes favoured by the German Army and had a welded steel-tube landing gear with a central skid; the shock absorbers were telescopic struts containing coil springs and the half-axles could be moved by a tiller-bar for ground steering. The engine was the 70 h.p. Daimler-Mercedes from the unlucky G.E.2 biplane, and the machine was sent to Larkhill for testing with two sets of wings, one set being of normal profile, while the other had a very pronounced camber based on the aerofoil section known as the 'Phillips Entry'. It was seriously overweight and failed to fly successfully with either set of wings, so was never sent to Deutsche Bristol-Werke as had been intended.
   The first production Coanda military monoplane, No. 118, had extra fuel and oil tanks and an enlarged rudder and was taken to Bucharest in September by Prince Cantacuzene, head of the Rumanian military aviation mission which had come to Larkhill to study' Bristol' methods and products. Pixton demonstrated this monoplane in the Rumanian army manoeuvres with great success. Two others, Nos. 121 and 122, were built for the Italian government, and No. 122 was dispatched to Turin on 13 November, but No. 121 remained at Larkhill and was destined to have a remarkable career. The fourth production monoplane in the batch was No. 123, which was Prince Cantacuzene's personal mount, but he crashed it while taxying, and after being rebuilt as No. 142, it became a static test airframe. The next of the series, No. 131, was specially finished for the Paris Salon of 1912, with a streamlined chassis with filleted strut junctions. It so impressed the Italian authorities that they purchased it in preference to No. 121 and ordered 12 more for urgent delivery. Rumania also ordered ten, and both countries had sent officers to Larkhill for instruction in December. No. 131 was dispatched to Turin on 6 December 1912, together with school monoplane No. 132, as initial equipment for the Italian military aviation school.
   Enthusiasm for the Coanda monoplane increased as experience was gained, and the Company appeared to have overcome the set-back caused by the War Office ban. A new production batch of 12 monoplanes was laid down, numbered 143 to 154 inclusive, the first two being retained at Larkhill for test and demonstration, and No. 145, which had a modified chassis, being sent to Spain on 23 December after a marathon effort to dispatch it before the Christmas holiday. No. 146, the first of four for Rumania, was not ready until February 1913, having been held up while Coanda rechecked the stress calculations and performed static tests with sand-bags on the inverted airframe of No. 142, at the request of Prince Cantacuzene. Satisfied with the results, all was ready for acceptance flight testing to begin as soon as the weather permitted, and on 5 March 1913 Gordon England's younger brother Geoffrey undertook a 1 hour duration test on No. 146 although the wind was still too strong for the altitude test. After flying for 39 min., the machine was struck by a violent gust which caused the port wing to collapse and Geoffrey England was killed. Prior to this accident the Coanda monoplane had been selected for purchase by the Italian National Subscription, which had raised nearly ?800,000 to buy aeroplanes for the army and had ordered 36 more of the type to be built in Italy by Italian labour. The Company had been asked to grant a manufacturing licence to an established firm in Italy, and Caproni & Faccanoni, of Vizzola Ticino, had been recommended as the most reliable of the three or four constructors of that time. A condition for granting the licence was that the first few Italian-built machines should be test-flown by Bristol pilots, and the formal agreement setting up the Societa Italiana Bristol Aeroplani was signed on 31 December 1912 by Henry White Smith, who, with Capt. Dickson, had supervised the Caproni factory arrangements. These included the supply from Filton of a complete skeleton monoplane (No. 154) as a pattern and the loan of a picked party of Filton erectors to teach their Italian colleagues 'Bristol' methods in addition to the normal provision of drawings and data.
   Delivery tests of Nos. 122, 131 and 132 were undertaken by Sidney Sippe, who had just joined the Bristol staff, and in December Pixton went to Turin on his return from Rumania and put No. 131 through its paces, breaking records for climb and speed with full load. He then went to Madrid and during the trials of No. 145 at Cuatros Vientos repeated his Turin performance. He also took up as passengers the Infante of Spain and his uncle, Prince Leopold of Battenburg. Meanwhile Sippe remained in Italy to await assembly of the first two Caproni-built monoplanes. These were generally satisfactory in workmanship, but the warp control was found to be immovable and on examination it was found that the ribs had been bolted to the spars, thus destroying the flexibility of the wing which was an essential feature of the design. In January a new flying school, based on Larkhill practice, was opened at Malpensa and Collyns Pizey went out to begin instruction. He stayed until April when new Italian military aircraft trials were to be held between Turin and Milan, for which two Caproni-Bristols had been entered. The events were ruined by incessant rain, turning the flying ground into a sea ofmud and the Caproni-Bristols proved unequal to the task. As a result the Italian Government cancelled the Bristol contract and after a prolonged dispute which lasted until January 1918 the Caproni-Bristol licence was cancelled.
   After the loss of No. 146, delivery of the remainder of the Rumanian monoplanes was held in abeyance, but a specially finished Coanda monoplane, No. 153, was exhibited at Olympia in February, featuring wheel brakes and armoured glass fuselage windows. Together with Nos. 150 and 151 it was sent to the Deutsche Bristol-Werke in April 1913, but Nos. 151 and 153 were returned to Filton in August. No. 152 was held as a replacement for No. 146 on the Rumanian contract, and the final example, No. 196, was one of the Caproni-Bristols shipped to Filton in August 1913 for conversion into a biplane. The Rumanian monoplanes were fitted with strengthened wings, but this detracted seriously from their performance and eventually a happy compromise was found in the conversion of the whole batch into biplanes, which proved very successful indeed.

SPECIFICATIONS AND DATA
   Type: Coanda Monoplanes
   Manufacturers:
   The British & Colonial Aeroplane Co., Ltd., Filton, Bristol
   Deutsche Bristol-Werke, Halberstadt, Germany
   Caproni & Faccanoni, Vizzola Tieino, Varese, Italy

Model School Side by side Competition Daimler Military
Power plant 50 hp Gnome 50 hp Gnome 80 hp Gnome 70 hp Daimler 80 hp Gnome
Span 40 ft 41 ft 3 in 40 ft 39 ft 4 in 42 ft 9 in
Length 27 ft 27 ft 28 ft 3 in 30 ft 9 in 29 ft 2 in
Height 7 ft 7 ft 7 ft 7 ft 7 ft
Wing Area 275 sq ft 275 sq ft 242 sq ft 260 sq ft 280 sq ft
Empty Weight 770 lb 770 lb 1,000 lb 1,200 lb 1,050 lb
All-up Weight 1,100 lb 1,100 lb 1,710 lb 1,850 lb 1,775 lb
Speed 65 mph 65 mph 73 mph 60 mph 71 mph
Accommodation 2 2 2 2 2
Production 6 7 2 1 21
Sequence Nos. 77 132 80 110 164- 105 106 111 118 121-
   185 186 166 176 177 123 131
   188 189 142-154
   (196+one in
   Italy)

M.Goodall, A.Tagg British Aircraft before the Great War (Schiffer)

P.Lewis British Aircraft 1809-1914 (Putnam)

Bristol Coanda Monoplanes

   Early in 1912 Mons. Henri Coanda, a Roumanian, produced the first of his machines to be built by the British and Colonial Aeroplane Company since he joined the firm as a designer. A monoplane intended for school use, it featured a steel-tubing chassis made in the style of the 1911 Grandseigne Racer.
   Well proportioned and strongly built, it seated two in tandem and was powered by the 50 h.p. Gnome. The strong undercarriage was fitted with an additional small wheel at the forward end of each of the skids. The landing wires were supported at a comparatively shallow angle by short streamlined pylons above the fuselage, the wings possessing a warping movement of 3 ft. at the tips. No fin was installed and the elevator was in one piece. Foot pressure on the rudder-bar operated the band-brakes with which the undercarriage was equipped - an advanced feature at the time. The passenger occupied the front seat, which was placed over the centre of gravity so that the balance was not disturbed when the machine was flown solo. The airframe was fabric-covered, except for the fore-part of the fuselage, which received metal panels.
   Six Coanda School Monoplanes were built with works numbers 77, 132, 185, 186, 188 and 189. A side-by-side variant of number 77 was built as number 80, and was crashed by a pupil while under instruction by F. Warren Merriam in January 1914.
   With the Military Trials in prospect in August, 1912, the company decided to enter a pair of Coanda Monoplanes as well as their two G.E.2 Biplanes, and two military versions were constructed The 80 h.p. Gnome conferred extra power in place of the standard 50 h.p. engine. The span and wing area were reduced slightly, but the overall length was increased.
   The empty weight rose by 230 lb. The machines were built under works numbers 105 (Military Trials 14) and 106 (Military Trials 15), and were flown respectively by Harry Busteed and James Valentine in the competition, gaining third place in the British-built section, although Valentine was unfortunate in crashing his aircraft during the tests on the first day. After repairs it was taken over by C. H. Pixton, as he had abandoned his G.E.2. Number 105 was fitted with a fixed fin in front of a rudder of smaller area which had been moved forward on the fuselage, this arrangement being arrived at after tests with various rudders before the Trials commenced.
   The crash of a Coanda Military Monoplane on 10th September, 1912, at Wolvercote, Oxford, in which Lts. C. A. Bettington and E. Hotchkiss were killed, was responsible for the decision of the War Office to ban the use of all monoplanes in the Military Wing of the R.F.C. after several fatal accidents had occurred also with other types of monoplane. The Admiralty, however, continued to allow the Naval Wing of the R.F.C. to fly monoplanes, and the Coanda was exported to Bulgaria, Germany, Italy and Roumania. The export version for Italy and Roumania was fitted with the Grandseigne type of steel undercarriage skids and was built under works numbers 110, 164, 165, 166, 176 and 177. The production model of the Military Trials Monoplane 105 was revised with the wingspan increased from 40 ft. to 42 ft. 9 ins. and received a larger rudder. It was known as the Improved Coanda Military, of which numbers 118, 121, 122, 123, 131, 142-154 inclusive, and 196 were produced and were sold to Germany, Italy and Roumania. All of the Military Coandas were equipped with 80 h.p. Gnome engines, but a further experimental example, number 111, was built with the 70 h.p. Daimler taken from Gordon England's G.E.2 Biplane 104, which had flown as No. 13 in the Military Trials of 1912. The chassis of number 111 was of welded steel tubing, and its Daimler engine increased the machine's length to 30 ft. 9 ins.
  
SPECIFICATION

   Description: Two-seat tractor training monoplane. Wooden structure, fabric covered.
   Manufacturers: The British and Colonial Aeroplane Co. Ltd., Filton, Bristol.
   Power Plant: 50 h.p. Gnome.
   Dimensions: (Works number 80). Span, 41 ft. 3 ins. Length, 27 ft. Wing area, 275 sq. ft.
   Weights: (Works number 80). Empty, 770 lb.

   Description: Two-seat military monoplane. Wooden structure, fabric covered.
   Manufacturers: The British and Colonial Aeroplane Co. Ltd., Filton, Bristol.
   Power Plant: 80 h.p. Gnome.
   Dimensions: (Works number 118). Span, 42 ft. 9 ins. Length, 29 ft. 2 ins. Wing area, 280 sq. ft.
   Weights: (Works number 118). Empty, 1,050 lb. Loaded, 1,775 lb.
   Performance: (Works number 118). Maximum speed, 71 m.p.h. Endurance, 4 hrs.
   Price: ?1,400.

   Description: Two-seat military monoplane. Wooden structure, fabric covered.
   Manufacturers: The British and Colonial Aeroplane Co. Ltd., Filton, Bristol.
   Power Plant: 80 h.p. Gnome.
   Dimensions: (Works number 105, Military Trials No. 14). Span, 40 ft. Length, 28 ft. 3 ins. Wing area, 242 sq. ft.
   Weights: (Works number 105, Military Trials No. 14). Empty, 1,000 lbs. Loaded, 1,710 lb.
   Performance: (Works number 105, Military Trials No. 14). Maximum speed, 73 m.p.h. Endurance, 7 hrs.

   Description: Two-seat experimental tractor monoplane. Wooden structure, fabric covered.
   Manufacturers: The British and Colonial Aeroplane Co. Ltd., Filton, Bristol.
   Power Plant: 70 h.p. Daimler.
   Dimensions: (Works number 111). Span, 39 ft, 4 ins, Length, 30 ft, 9 ins, Height, 7 ft, 1 in. Wing area, 260 sq. ft.

Jane's All The World Aircraft 1913

BRISTOL. The British & Colonial Aeroplane Co., Ltd., Filton House, Bristol. Founded 1910. Capital (1913), Have very extensive works (area. sq. feet) on the outskirts of Bristol, employing over 300 men, where they manufacture to their own designs practically every type of flying machine. Flying grounds: Salisbury Plain, Brooklands. 105 Royal Aero Club certificates won on Bristol machines during 1912 (of which 86 were officers of His Majesty's Forces).

Military Military Tractor School
mono. mono. biplane mono.
2-seater. 2-seater. 1913 Side by side.
80 h.p. 50 h.p.
1912-13. 1912-13.

Length feet (m.) 28-1/4 8.60 23-2/3 7.20 27-3/4 8.47
Span feet (m.) 42-1/3 12.90 39-1/3 12 34-1/3 10.44
Area sq. feet (m^2.) 221 20.6 226 22 370 34.4
Total weight, machine, lbs. (kgs.) 1719 771 1323 600 1764 800
Total weight, useful lbs. (kgs.) 710 322 551 250 1200 544
Motor h.p. 80 Gnome 50 Gnome 70 Renault 50 Gnome
Speed, max. m.p.h. (km.) 73 118 62 100 70 112
Speed, min. m.p.h. (km.) ... ... ...
Endurance hrs. 4 3-4 ...
Number built during 1912 ... ... ...

Notes.--Monoplane: Box section fuselage convex on bottom side to minimise resistance. Mounted on 2 wheels and 2 skids with smaller wheels attached at the forward end. Bristol tractor. Biplane: Box section fuselage, convex on top and bottom sides. Mounted as monoplane. Bristol tractor. This machine is the latest production of the Bristol Co., and has proved an exceptionally successful flyer. Designed by M. Coanda.

Журнал Flight

Flight, July 27, 1912.

THE MILITARY COMPETITION - THE MACHINES.

THE BRISTOL AEROPLANES.

   OF the four machines entered by the British and Colonial Aeroplane Co., two will be tractor biplanes of the type designed by Mr. E. C. Gordon England, and the remaining two will be monoplanes of the well-known military type. The tractor biplanes will be flown by Messrs. C. H. Pixton and Gordon England, the monoplanes by Messrs. H. Busteed and James Valentine. Truly, with such a display of excellent machines and expert pilots, they should be successful in carrying off some of the more important awards. Next week we hope to publish photographs and complete descriptions of each machine. For the present, however, we must be content to mention their main characteristics : -

Main characteristics:-

Bristol Military Monoplanes.

Motor 7-cyl. 80-h.p. Gnome
Length 28 ft. 4 in.
Span 40 ft. 3 ins.
Area of wings 242 sq. ft.
Weight 792 lbs.
Speed 70 m.p.h.
Propeller diameter 8 ft.
Pilots Messrs. H. Busteed and James Valentine


Flight, August 10, 1912.

THE MILITARY AEROPLANE COMPETITION - THE MACHINES.

THE BRISTOL MONOPLANES.

   THE monoplanes representing the Bristol firm in the Military Trials probably look more warlike than any other machines flying just now on Salisbury Plain. Their disc wheels and the amount of aluminium sheathing used in covering the front part of the machines gives them an armoured appearance, and the two little streamline stay-masts above, like miniature funnels complete the impression. Everything exposed to the relative wind has been shaped to decrease resistance. When flying they both have the appearance of four-seaters, owing to the resemblance, at a distance, of the streamlined stay-masts to passengers' heads.
   The body is of the lattice girder type, flat at the sides but belled out top and bottom with curved formers over which aluminium sheathing is applied. Pilot and passenger sit in tandem and are both provided with controls. In both cases an 80-h.p. Gnome motor of the Grand Prix type is fitted under an aluminium cowl which is designed to reduce the head resistance that the engine, unshielded, would cause. The efficient cooling of the engine is, apparently, not interfered with in the slightest.
   The wings are quite different in shape from those used on the former "Prier" type of Bristol monoplane. In the present machines the rear spar is longer than the front, a system that many constructors have resorted to of late by virtue of the fact that it is thus possible to obtain a more powerful warp. In the case of the Bristol monoplanes this is increased, owing to the flexible construction of the wings. The spars are virtually steel tubes filled with wood, and the ribs, instead of being directly connected to them, are threaded thereon. A new wing camber has also been adopted. The one at present used has a Nieuport type of entering edge, and a slightly turned-up trailing edge. On each side of the pilot's seat a section of the wing to the rear of the back spar has been cut away to allow of a better view being obtained. The warping wires are carried to and operated from a single mast beneath the fuselage. This mast is carefully shaped to avoid resistance, and the warping pulleys are similarly protected. The Bristol firm have, in these monoplanes, departed from their practice of employing a completely movable empennage. They now use a fixed stabilising plane with elevator flaps hinged to its rear edge.
   The landing gear strikes one as being particularly solid and efficient. Four exceedingly strong vertical struts connect the two horizontal skids to the body. At the rear these skids are laminated to form flexible extensions, which may assist the machine in coming to rest after landing. The struts themselves are not rigidly attached to the skids, but are joined thereto by a form of joint which relieves the fuselage of any kind of twisting strain which may result in landing. At the front ends of these straight skids are fitted short tusk-shaped organs, which carry a miniature pair of wheels, Cody fashion.

Main characteristics:-
Overall length 28 ft.
Weight without complement or fuel 792 lbs.
Span 40 ft.
Area 242 sq. ft.
Propeller Bristol
Motor 80-h.p. Gnome


Flight, October 26, 1912.

MILITARY FLYING IN ROUMANIA.

   THE Roumanian Government are going ahead with the equipment of their army with aeroplanes, and their latest purchases are a number of 80-h.p. Bristol monoplanes. On one of them the other day, Lieut. Protopopescu made a flight of upwards of an hour to the south of Bucharest, then returning to his starting point. He had made his first flight on the machine only three days previously. Roumania is a splendid country for aviation as it is dead level and unobstructed by trees. The fields are, however, cut up by small dykes, so that great care has to be taken when landing or rolling and they tend to make the atmosphere disturbed at times. Being of very plucky character and able to keep a cool head in an emergency the Roumanians make splendid flyers, and should they be drawn into the war they will doubtless make full use of the new arm. Apart from the Bristol machines the Roumanian Army, at its school at Bucharest, has several Henry Farman machines, a couple of Bleriots, a Nieuport and a Morane.


Flight, November 2, 1912.

THE PARIS AERO SALON.

Bristol.

   ON this stand is a monoplane similar in almost every particular to the one that carried off L1,000 in prizes at the British Military Aviation Trials at Salisbury Plain. The stand was surrounded with people all day long, and they stand and look as if not being able to credit that a firm of British conductors could turn out such a notably fine example of aeroplane construction. No wonder the Bristol people go to the Paris show when they number amongst their foreign customers such as the Ministers of War of Russia, Germany, Italy, Spain, Turkey, Roumania and Bulgaria.
   The machine has somewhat the lines of a submarine with wings. The blunt metallic snout over the Gnome motor and the funnel-like upper cabanes tend to carry out the impression. Throughout it is well and conscientiously built, in perfect keeping with their usual work.
   The fuselage is of square section and built up on the lattice girder principle. Its sides are flat throughout its entire length, but the top and bottom are bellied out by;the application of aluminium sheeting. An 80-h.p. Gnome motor protrudes from the front, half covered by an aluminium cowl that keeps oil from the pilot and passenger, and that reduces the head resistance of an otherwise unprotected revolving engine. The chassis is at the same time simple, clean and effective, merely two horizontal skids supporting the body by four strong hollow streamlined struts, with a pair of wheels strapped across them by elastic bands. Tusk-like projections extend in front of the skids and carry another pair of wheels, but quite miniature ones, which protect the propeller from damage. The tail is of conventional design. Its disposition may be seen from the little accompanying sketch. Control is arranged in duplicate so that either pilot or passenger, sitting in tandem, may take charge of the machine in flight.
   As was announced last week Italy has ordered a batch of twenty of these excellent machines. The latest news here is that the order is more than likely to be considerably increased.


Flight, February 8, 1913.

WHAT THERE WILL BE TO SEE AT OLYMPIA.

THE MACHINES.

The British and Colonial Aeroplane Co., Ltd.

   On the stand of the enterprising manufacturers of Bristol aeroplanes will be shown two machines, an 80-h.p. two-seater monoplane, fitted with a Gnome engine, and a 70-h.p. Renault-engined tractor biplane. The monoplane will be identical with the machine that flew so well in connection with the British Military Aeroplane Trials of 1912, and which was placed third in order of merit among the 32 entries that were received. Replicas of this monoplane have been bought extensively by foreign governments. The backbone of the monoplane, 28.5 ft. in length, is formed by a girder constructed of four longitudinal members of ash, braced by piano wire, with cross members and struts of spruce. For the reduction of head resistance, the whole is covered in by fabric, and the top and bottom are made convex. The 80-h. p. Gnome motor, supported by carlingues on both sides of the crank-case, is mounted in front and half enclosed by a semispherical cowl that prevents any of the oil thrown off by the motor reaching the pilot or passenger. Regarding the wings, which span 43 ft., their chief features are that they are each built about two spars of heavy gauge wood-filled steel tubing, and that the ribs, cut from wood and covered with fabric to prevent them splitting, are fitted loosely over the spars in order to prevent any fatigue in the construction as a result of continual wing warping. The landing gear is of the wheel and skid type, and it has the peculiarity that the hollow vertical chassis struts are attached to the fuselage and to the skids by pin-joints, so that more flexibility may be given to its structure. A flap hinged to the rear of a semicircular fixed tail-plane controls the elevation. Without passengers or fuel, the monoplane weighs 1,050 lbs., and is capable of carrying a useful load of 726 lbs. at an average flying speed of 72 miles per hour. It is interesting to note that this 80-h.p. Bristol monoplane had the best gliding angle, 1 in 7.2, of all the machines entered for the British Military Aeroplane Trials.
<...>


Flight, February 22, 1913.

SOME MORE AEROPLANES AT OLYMPIA.

THE BRITISH AND COLONIAL AEROPLANE CO., LTD.

   As the manufacturers of Bristol machines have an organization far and away larger than any similar firm in England, or, we might say, with perhaps one or two exceptions, in the whole world, it is only natural to expect that their exhibit is one of the main centres of interest at Olympia. Both their machines - the monoplane which made its debut in the Military Trials, and the biplane, which has just been evolved from their Filton works - are of distinctive design and, as samples of workmanship stand, bracketed with one other machine shown, unrivalled, among all the various aeroplanes exhibited there. They both have been constructed to the designs of M. Henri Coanda, their clever engineer, of Roumanian birth. Since 1908 has M. Coanda been connected with the study and practice of aeronautics. He first began his experiments with the late Capt. Ferber in France.
   It will be remembered that - was it three years ago or four ? - Coanda exhibited at the Paris Show a particularly neatly designed<...>


Flight, May 17, 1913.

THE BRISTOL MONOPLANE,

   THE scale drawing and constructional sketches published this week represent the latest Bristol monoplane as exhibited at the Olympia Show. It is a development of the design by M. Coanda which was entered for the Military Trials, and differs principally from its prototype in respect to a larger wing area, which now spreads 280 sq. ft. The chord is 7 ft. 3 ins., and is notable for the extent of the trailing portion aft of the main spar. The weight of the machine, notwithstanding its larger area, is appreciably less than that of the machine entered in the Military Trials; in consequence, it has an increased flexibility of maneouvring power, is able to ascend more quickly in confined spaces, and in general to respond with greater certainty to the pilot's control when a delicate touch is needed during, say, the course of alighting. The fuselage of the machine is rectangular in section, and is built up of four ash booms with strut cross members of spruce. Diagonal steel wire bracing is employed in the usual way to make a rigid girder of the whole structure.
   In order to prevent the compression stress on the wing spars being taken by the sides of the body of the machine, the spars themselves, which are of tubular steel, are carried through the body and abut against the masts that carry the guy wires from overhead. These masts are very neatly streamlined, and have somewhat the appearance of short funnels, which gives to the machine in flight an appearance that lends an appropriateness to its being described as a sort of torpedo boat of the air.
   The passenger sits immediately behind the forward mast, and the passenger's seat corresponds with the centre of gravity of the machine. His presence or absence does not, therefore, affect the balance. The pilot's seat is situated behind the second mast, and his outlook on either side of the body is facilitated by the cutting away of the wing surfaces. Both seats are of the bucket type, and are independently sprung upon bent malacca cane so as to ease the shock of a rough landing. For the same reason they are upholstered round the edges with leather. A further range of vision is sought by fitting glass windows in the sides and bottom of the fuselage; the glass is of the kind that has wire netting embedded in it to prevent it from flying to pieces when broken. The front edges of the wings are also cut away slightly, it will be noticed, to facilitate the passenger's outlook toward the ground.
   Speaking of balance, an interesting detail is the disposition of the fuel and oil tanks relatively to the centre of gravity. The oil tank is placed at a distance behind the C.G., that is three times as great as the distance of the petrol tank forward of that point. The ratio of the consumption of fuel to oil is three to one in units of weight, so that the two tanks are in balance at the start and at all times during flight so long as this ratio of consumption is maintained.
   Dual control forms a standard fitting on this design, and incorporated therewith is an unlocking device by which the pilot can throw the passenger's control gear out of action at will; the control movements themselves are of the orthodox type. A to and fro motion of the lever operates the elevator, turning the hand wheel on top of the lever actuates the warp through cables, and the pivoted bar under the pilot's seat controls the rudder.
   Particular attention has been paid to the range of the warp, and the wing tips of this machine are capable of moving up and down about 3 feet. On account of the torsion when the wing is warped, the wing does not tend automatically to return to its neutral position. The wing spars are, as has been mentioned, steel tubes; they are cored with wood to give them greater resistance to indentation. The wooden ribs are a free fit on the spars, and kept in position along the span by the special construction of the leading and trailing edges to which they are fastened. The trailing edges of the wings consist of three-ply wood, which is very neatly arranged and gives a well-finished edge. The general staying of the wings is very much the same as at the time of the Military Trials, the upper wires being carried over the two masts and the lower wires of the forward spars being carried forwards to the undercarriage. The lower wires of the rear spar are of course carried to the warping gear on the lower extremity of the rear mast. The innermost of the lower forward stay wires is attached to a steel strap passing under the body.
   The two outer lower wires, which are attached to the forward spar and to the undercarriage, have a rake of about 45 degrees in side elevation, and their purpose is to take the drift as well as the lift. The angle is such that under all normal conditions the forward component of the lift due to the obliquity of the wires would exceed the direct drift force against the wing. The difference between the actual drift force at any moment and the resolved component of the lift is taken by the internal wing bracing, which is of an interesting and unusual character. Adjacent to the collars on the two spars to which the lift wires are attached, steel clips are fitted for the attachment of the internal wires. These clips embrace the tubes that are not rigidly fixed thereto. In turn, these clips are embraced by the master ribs of the wing structure. The arrangement of the clips is such that their proximity to the fixed collars on the wing spar gives them a point of abutment that otherwise would of course be lacking.
   The undercarriage design of the Bristol monoplane is a striking feature of its construction, principally on account of the very interesting and very massive looking streamline main struts by which it is attached to the body. These struts, which measure some four inches fore and aft, are hollow, and at each end are semi-circular, so that they form a knuckle joint with the piece against which they abut. The joint is completed by a plate and a pin through the centre from which the semi-circle is described. The joint is constructed as a rigid member, but its object is to facilitate a certain amount of give in the right place so as to avoid breakage in the event of very severe shock. The general design is also such as to facilitate the replacement of these struts.
   Ordinarily, the weight of the machine is carried on two wheels, which are attached by their axle to the chassis skids by means of elastic straps. Two smaller guard wheels are carried on extensions of the chassis construction, and serve to take the shock of a pique landing or of any obstruction. While rolling, this portion of the chassis projects forward of the propeller, and to that extent tends to preserve it from damage.
   The tail unit of the machine consists of a segmental fixed member that is non-lifting and an undivided extension thereto, which forms an elevator flap. The rudder is mounted entirely above the fail, and is pivoted so as to be approximately in balance about its swiveling axis.


Flight, October 22, 1915.

CONSTRUCTIONAL DETAILS.-VII.

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   Yet another form of undercarriage having double skids is shown in the sketch of the Coanda-Bristol biplane. Here the two skids are carried in the usual way on four struts coming down from the body, and a single axle carries the two main alighting wheels. There is, however, another pair of smaller wheels mounted on an axle slung by rubber bands from a forward projection of the skids. The purpose of these front wheels is, of course, to prevent the machine from turning up on its nose when landing on rough ground.
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