A.Jackson Blackburn Aircraft since 1909 (Putnam)

The Second Blackburn Monoplane

   Although Robert Blackburn's second aeroplane bore a marked resemblance to M. Levavasseur's Antoinette monoplane which he had seen in France, so many detailed improvements were incorporated that the resemblance was purely superficial. It was a single-seat, fabric-covered, wooden monoplane with a square-ended, constant-chord mainplane wire-braced to a central kingpost at a considerable dihedral angle, and the fuselage was of triangular cross-section tapering rearwards from the pilot's seat.
   The 'triple steering column' was used again but the little all-moving tail was abandoned in favour of the Antoinette's long dorsal fin and its diminutive triangular rudders above and below the elevator. Blackburn also fitted an untried British engine of advanced design then being developed by R. J. Isaacson, a skilled engineer employed by the Hunslet Engine Co of Leeds. The Isaacson engine was a seven-cylinder air-cooled radial of 40 hp arranged so that valves and other working parts were readily accessible for maintenance, and its many novel features (for those days) included pushrod-operated overhead valves and a 2 to 1 reduction gear within the airscrew hub. Being a stationary unit there were none of the gyroscopic problems with which the rotary engine continually plagued designers and pilots alike.
   The development of such an engine inevitably took a long time, so that although Blackburn and Goodyear took the monoplane to the Blackpool Flying Meeting of 28 July - 20 August 1910, it could not participate because the engine was unfinished even though installed in the airframe. This was perhaps fortunate, for the undercarriage was so weak that the wing tips had to be supported with timber when in the hangar.
   In its original form the undercarriage consisted merely of a downward extension of the wooden kingpost which terminated in a socket carrying a tubular-steel cross-member. Two ash skids, with pneumatic-tyred wire wheels in forks at the rear ends, pivoted about this steel cross member, all landing shocks being taken by a powerful coil spring at the apex of a triangle of struts under the engine. However, after Blackpool, and while he was awaiting the completion of the engine, Blackburn added a stout pair of main undercarriage struts and refitted the wheels on an overlength axle to give a measure of sideways movement under the control of coiled springs. He then took the monoplane to a new stretch of sands on the Yorkshire coast at Filey, but the undercarriage was still unsatisfactory. The front struts with their central coiled spring were removed almost immediately and replaced by four skeins of bungee rubber connecting the ends of each skid via cables to the longerons of the fuselage.
   Not long after reaching Filey, the machine attracted the attention of B. C. Hucks who thereupon joined forces with Blackburn to try out the machine and, on Tuesday, 8 March 1911, taxied it for a distance of three miles along the sands before making the initial take-off. He then headed for Filey Brigg at a height of 30 ft and at an estimated speed of 50 mph, but in attempting a turn, always a hazardous manoeuvre when there is negligible difference between maximum speed and stalling speed, he sideslipped into the ground.
   After repairs the Second Monoplane flew well and saw a great deal of service as an instructional aircraft at Filey and established Robert Blackburn as one of the foremost British designers of the day.

SPECIFICATION AND DATA
   Construction: By R. Blackburn and H. Goodyear at Benson Street, Leeds, Yorks.
   Power Plant: One 40 hp Isaacson
   Dimensions: Span 30 ft 0 in Length 32 ft 0 in
   Weights: All-up weight 1,000 lb
   Performance: Maximum speed 60 mph
   Production: One aircraft only, completed July 1910, first flown at Filey 8 March 1911.


Blackburn Mercury

   The Mercury, Robert Blackburn's next aeroplane, was a larger, two-seat development of his Second Monoplane powered by a new 50 hp version of the Isaacson radial. It was built with the assistance of Harry Goodyear, Mark Swann and George Watson in large premises which Blackburn acquired in Balm Road, Leeds. Whereas the earlier machine (with which the Mercury is still frequently confused) had a two-wheeled undercarriage, the Mercury had four wheels mounted in pairs on short, bungee-sprung axles astride two long ash skids attached to the fuselage by a substantial wire-braced, 12-strut, multiple A frame calculated to resist the efforts of the most inexpert pupil. Steel springs projecting sideways under the axle were intended to counteract the effects of landing with drift.
   To make wire bracing unnecessary, the triangular-section lattice-work fuselage, also of English ash, was precision-built with vertical and diagonal struts butting accurately on the longerons. The forward part accommodated pilot and passenger in tandem and was planked with polished, veneered wood, but the tapering rear fuselage was fabric-covered.
   Constant-chord, shoulder-mounted mainplanes were built up from closely spaced ribs supported on two I-section ash main spars and two subsidiary spars. To reduce the stresses associated with wing warping the mainplane was pivoted about the rear spar and wire-braced to a kingpost built into the fuselage in line with the front spar. The patent 'triple steering column' was used again and the tail surfaces were similar to those of the second Blackburn monoplane, with the long dorsal fin, the 10 ft bird-like tailplane, and the one-piece semi-octagonal elevator moving between two small triangular rudders.
   The first Mercury (which for convenience will be referred to hereinafter as the Mercury I) was exhibited at the Olympia Aero Show during the last two weeks of March 1911 and then went to Filey to join the Blackburn Second Monoplane at the newly established Blackburn Flying School, where a new airscrew with wider blades was fitted. On 17 May B. C. Hucks flew it to Scarborough and back in 19 min, averaging 50 mph and reaching a height of 1,200 ft, the highest flight made in North England up to that time. Next day he flew the handling and height tests for his Aviator's Certificate, but differences of opinion between the Aero Club observers about the validity of doing both tests in the course of one flight led Hucks to make a second takeoff. Minutes later the airscrew sleeve overheated, seized up and broke, allowing the airscrew to fly off. Hucks received slight injuries when he sideslipped into the ground but nevertheless was granted Certificate No. 91, no mean achievement for a pilot who was entirely self-taught.
   In the repaired machine Hucks (by then the Filey School instructor) made several remarkable flights, notably a cross-country to Scarborough and back on 7 July and a 40 mile moonlight trip over the same route on 10 July. Leaving Filey at 10.10 pm he circled Bridlington, reached Scarborough without difficulty, nursed a failing engine which picked up when he was about to make a forced landing in a cornfield, and landed on the beach by the light of bonfires 45 min after take-off.
   Hubert Oxley who succeeded Hucks as the Filey School's instructor, flew Mercury I for the first time on 3 September 1911, and to give new pupils (one of whom was engine designer R. J. Isaacson) an opportunity of watching his control movements, the front passenger seat was turned round to face aft. The aircraft was also used for joyriding, as on 11 October when a local resident, Miss Cook, became the first lady passenger in Yorkshire.
   Robert Blackburn was now calling himself 'The Blackburn Aeroplane Co' and advertised the Mercury at ?825 with 50 hp Isaacson; ?925 with 50 hp Gnome; ?730 with 35 hp Green; and ?1,275 with 100 hp Isaacson. None was in fact ever fitted with the Green or the big Isaacson, the first of a production run of eight aircraft which appeared at intervals during the next couple of years being two single-seaters (referred to in this book as Mercury IIs), built for the Daily Mail ?10,000 Circuit of Britain contest, powered by 50 hp Gnome rotaries. They had reduced span and shorter fuselages, the space normally occupied by the front seat was faired over with fabric, and fuel and oil tanks were lowered partially into the fuselage and covered by a curved metal fairing to reduce drag.
   Both were entered for the contest by Stuart A. Hirst of the Yorkshire Aeroplane Club - racing No. 22 to be flown by F. Conway Jenkins and No. 27 by B. C. Hucks - and each made its maiden flight at Filey early in July 1911. During the first flight of No. 22 on 7 July, Hucks made a return flight to Scarborough, 15 miles in 15.1 minutes, and reached 3,000 ft, but on the 14th, while attempting to win Hirst's ?50 prize for a flight to Leeds in a Yorkshire-built aeroplane, he damaged it extensively in avoiding grazing cattle and carried away the undercarriage on a barbed-wire fence during a forced landing at East Heslerton Grange. By a prodigious effort it was repaired on site by Robert Blackburn's working party in time for it to be on the line at Brooklands on 22 July, but although Hucks reached Hendon successfully, he retired the next morning after a forced landing with engine trouble at Barton-in-the-Clay, near Luton. Conway Jenkins' machine turned over and was wrecked while taxying out at Brooklands, but there are conflicting reports on the cause, one blaming a strong cross-wind, another crossed warping controls.
   Mark Swann and Harry Goodyear once again repaired No. 27 on site and Hucks flew it back to Hendon. It was then converted to two-seater, dismantled and sent by train from Paddington to Taunton where Hucks began a West Country tour in aid of charity, taking with him a portable hangar, Harry Goodyear as mechanic and C. E. Manton Day as manager. After two opening flights before 10,000 people at Taunton Fete on Bank Holiday Monday, 7 August, the aircraft was sent by train to Burnham-on-Sea, but, late on 17 August, because of a railway strike, Hucks flew the next 25 miles across to Minehead in 22 minutes, outflying the telegram which was to have announced his arrival. The next port of call was Locking Road aviation ground, Weston-super-Mare, where considerable publicity attended his 5.10 am take-off on 1 September for a nonstop flight to Cardiff, Whitchurch, Llandaff and back. Attired in a cork life-jacket, he reached 2,250 ft, dropped handbills over Cardiff and landed at Weston 40 minutes later, having made the first double crossing of the Bristol Channel by air. The Weston visit over, Hucks made another early start on 11 September, flew 16 miles to Cardiff in 16 1/2 minutes and landed at Whitchurch polo ground at 6.01 am. Static exhibition for two days at the Westgate Road skating rink was a prelude to daily flying from Cardiff's Ely Racecourse and, while flying at 85 mph at a height of 700 ft on 23 September, Hucks made further history by receiving wireless telegraphy signals transmitted by H. Grindell Matthews.
   The tour continued with a 6.16 am take-off for Newport, Mon., on 27 September and on to Cheltenham on 1 October where the aircraft was put on show at the Drill Hall, North Street. Flying took place from Whaddon Farm, Cemetery Road, from 4 October until his departure for Gloucester on 16 October where, two days later, he caused a sensation by flying higher than the cathedral tower, although an attempt to better his personal record of 3,500 ft failed. Eventually, on 21 October, a gale lifted the travel-stained aircraft and its hangar completely clear of the ground, but quick repairs enabled the last three flights of the tour to be completed the same afternoon.
   In three months, weather had prevented flying on only two of the 30 advertised flying days and an estimated 1,000 miles had been covered in 90 flights, impressive figures for those days particularly when it is remembered that all take-offs and landings were from unprepared surfaces. The wings, originally white but now black with signatures, were replaced while the aircraft was at Cheltenham. Apart from this, the only other major replacement was the result of a forced landing at Cheltenham during which Hucks ploughed up yards of cabbages with his skids until eventually a wheel came off and rolled forward, breaking the airscrew.
   From 7 to 10 January 1912 the aircraft flew at Holroyd's Farm, Moortown Leeds, and was then sent to Shoreham, Sussex, by rail on loan to Lt W. Lawrence of the 7th Essex Regiment pending the delivery of a special steel-framed monoplane he had ordered from Blackburn for service in India. His immediate objective was a cross-Channel flight with society hostess Mrs Leeming as passenger. Taxying practices, begun on 25 January under the watchful eye of Hucks, led to first solos on 29 January and on 26 February to a half hour, 28-mile flight to Eastbourne where he landed down wind on the beach with engine trouble. F. B. Fowler of the Eastbourne Aviation Co gave the Gnome a complete overhaul and fitted a hand pump to overcome fuel starvation in the climb, but test flights on 30 March ended in a bad landing which put the machine on its back with sufficient damage to end Lawrence's cross-Channel aspirations. While under repair in Leeds, the opportunity was taken to modify it for school work and it emerged a month or so later as a single-seater with wing span increased to 36 ft, the wing roots cut away to improve the pilot's downward view, the undercarriage simplified, and the engine cowling extended rearward to form a scuttle over the instrument panel and afford some protection for the pilot. In this form it was historically important as the first Blackburn aircraft to exhibit a designation, each rudder bearing the inscription 'Blackburn Monoplane Type B'. One of the first pupils to fly it at the Filey School in April 1912 was M. G. Christie, DSc, for whom a special Blackburn aircraft was built in the following year.
   With the possibility of military contracts looming ahead, it was considered expedient to bring the Blackburn monoplanes more closely to the notice of the War Office. The School therefore moved to Hendon in September that year under a new instructor, Harold Blackburn (no relation of Robert). There the 'brevet' machine, as it was called, was allotted racing No. 33 for the frequent weekend competitions and also bore the maker's name in large capitals on the fuselage. In this guise it was flown by Harold Blackburn on 28 September at the Hendon Naval and Military Aviation Day and on 22 February 1913 in the Aero Show Trophy Race in which he came third.
   The soundness of the Mercury design, well-proven by the Hucks tour, prompted the construction of a third variant inscribed 'Mercury Passenger Type' with 60 hp Renault vee-8 air-cooled engine, now usually known as the Mercury III. This was a three-seater structurally similar to the earlier marks but with mainspars of wood-filled tubular-steel around which the cottonwood ribs were free to swivel and thus reduce twisting strains during wing warping. Other refinements included a foot accelerator which could override the hand throttle, and aluminium panels covering the engine bay. Although ready for flying at Filey on 29 October 1911, bad weather prevented Hubert Oxley from making the first flight until 9 November when the machine took off in 30 yards with one passenger and fuel for four hours. It proved very manoeuvrable and had a top speed around 70 mph.
   Oxley, who began a series of passenger flights over the sands in bright moonlight at 1 am on 27 November, was the only pilot to fly this machine. On 6 December, with Robert Weiss in the passenger seat, he passed low over Filey bent on his favourite trick of diving steeply over the edge of the 300 ft cliff and then suddenly flattening out to land. This occasion was the last, for on pulling out of a particularly steep dive at a speed estimated at 150 mph, the fabric stripped from the wings which immediately broke up, leaving the wingless fuselage to plummet into the sands with fatal results for both occupants.
   At first this machine had a constant-chord mainplane, but at some point during its brief six-week existence it was fitted with new wings having a root chord of 9 ft and tapering to 7 ft at the tip. Despite statements to the contrary made in the Press at the time, this was the only Blackburn Mercury fitted with a tapered wing.
   A second Mercury III, with 50 hp Isaacson and faired tanks as on Mercury II, was then built for Oxley's successor Jack Brereton who attempted the Filey-Leeds flight on 29 May 1912. This machine further differed from the Isaacson-powered Mercury I in having the top rudder raised above the fin, removable inspection panels behind the engine, and no wing tip skids. After a 6 am take-off, Brereton forced landed 22 miles away at Malton with engine trouble, and the flight ended in a second forced landing at Welham Park later in the day. The machine went back to Filey by rail and after this episode R. J. Isaacson modified the engine and fitted ball bearings to the connecting rods and crankshaft. It was flying again on 9 June and went to Hendon with the Type B in the following September.
   The third Mercury III, built for naval flying pioneer Lt Spenser Grey, RN, had polished aluminium side panels as far aft as the cockpit and for this reason has been continually misrepresented as one of the all-steel monoplanes which Blackburn built in 1912. Redesign of the front fuselage, which began when the tanks on the Mercury IIs and the second Mercury III were lowered and covered, reached finality in Spenser Grey's machine. This had a curved decking over the tanks which continued the line of the circular cowling over the 50 hp Gnome back as far as the cockpit where it formed a 'scuttle-dash' to deflect some of the slipstream from the pilot. This modification was embodied in the Hucks tour machine when it was rebuilt as Type B in 1912. Grey's Mercury III was delivered by rail to Brooklands where Hucks made the first engine runs on 16 December 1911, and the owner flew it for the first time on 25 December. A few days later he made a cross-country flight to Lodmoor, near Weymouth, where he had had a hangar built and on 7 January 1912 crossed Weymouth Bay to Portland and circled over the Home Fleet. Unfortunately, after exhibition flights on 10 January, he returned to find his landing ground full of sightseers and the machine was damaged in the ensuing avoiding action. After repairs at Leeds the redoubtable Harry Goodyear took the machine to Eastchurch by train and re-erected it. Spenser Grey then made the first of many flights there on 21 February. The aircraft was eventually repurchased by Blackburns, fitted with the simplified Type B undercarriage, and put to work as a school machine at Hendon where it took part in the Naval and Military Aviation Day on 28 September 1912.
   The fourth Mercury III, identified by a combination of cut-away wing roots and six-strut undercarriage, was built for the Blackburn School and flew at Filey in March 1912. Yet another is said to have had a 50 hp Anzani radial. For the summer season that year, a special single-seat machine with partially cowled 50 hp Gnome, similar to the Type B and with 'Blackburn' in bold lettering under each wing, was built to enable Jack Brereton to give demonstrations similar to those of B. C. Hucks the year before. Although it had the cut-away wing roots of Mercury III No. 4, its undercarriage differed from those of all other Mercury monoplanes. Basically of the simplified type fitted to the Type B, it had a tubular-steel spreader bar between the front struts and laminated skids with turned-down rear ends. It was first flown at Filey on 7 June 1912, and initial engagements were at Bridlington on 15 July and the Lincolnshire Agricultural Show, Skegness, two days later.
   Despite the oft repeated assertion that nine Mercury Ills were built, careful research has failed to identify more than six, so that in the absence of further information it can only be assumed that the total of nine included the Mercury I and the two Mercury IIs. The company's Flying School activities seem to have been maintained throughout by four aircraft. At Filey they appear to have been Blackburn's second monoplane, the Mercury I and Isaacson- and Gnome-powered Mercury IIIs, but at Hendon the veteran second monoplane and the old Mercury I were replaced by the Type B and the modified ex-Spenser Grey two-seater. They remained in service until the School closed in the spring of 1913 and were flown by a select band of pupil pilots, only three of whom actually gained Royal Aero Club Aviators' Certificates on the Blackburn types on which they had learned, viz:
   No. 91 B.C.Hucks Filey 30 May 1911
   No. 409 H.A.Buss Hendon 4 February 1913
   No. 410 M.F.Glew Hendon 4 February 1913

SPECIFICATION AND DATA
   Constructors: The Blackburn Aeroplane Co (the Aeroplane Dept of Robert Blackburn and Co, Engineers), Balm Road, Leeds, Yorks.
   Power Plants:
   (Mercury I) One 50 hp Isaacson
   (Mercury II) One 50 hp Gnome
   (Mercury III)
   One 60 hp Renault
   One 50 hp Isaacson
   One 50 hp Gnome
   One 50 hp Anzani

Dimensions, Weights and Performances:
   Mercury I Mercury II Mercury III
Span 38 ft 4 in 32 ft 0 in* 32 ft 0 in
Length 33 ft 0 in 31 ft 0 in 31 ft 0 in
Height 6 ft 9 in 8 ft 6 in 8 ft 6 in
Wing area 288 sq ft 200 sq ft* 195 sq ft
All-up weight 1,000 lb** 700 lb 800 lb
Maximum speed 60 mph 70 mph 75 mph***
   * Second aircraft later rebuilt with 36 ft span, 220 sq ft mainplane
** With Isaacson engine
*** With Renault engine

Production:
   (a) Mercury I
   One aircraft only, 50 hp Isaacson, shown at Olympia March 1911 and used by the Blackburn Flying School, Filey, until 1912.
   (b) Mercury II
   Two aircraft only, both with 50 hp Gnome engines:
   1. Racing No. 22, first flown at Filey in July 1911, wrecked at Brooklands 22 July 1911.
   2. Racing No. 27,first flown at Filey 7 July 1911, converted to two-seater August 1911, crashed at Eastbourne 23 March 1912, rebuilt as a single-seat school machine for the Filey School April 1912, to the Hendon School September 1912 as racing No. 33, withdrawn from use when the school closed June 1913.
   (c) Mercury III
   Six aircraft as follows (in approximate production order):
   1. 60 hp Renault First flown 9 November 1911, crashed at Filey 6 December 1911.
   2. 50 hp Isaacson First flown May 1912, identified by raised top rudder, used by the Blackburn Flying School, Hendon, until June 1913.
   3. 50 hp Gnome First flown 25 December 1911, built for Lt Spenser Grey, RN, damaged at Weymouth 10 January 1912, first flown at Eastchurch after repair 21 February 1912, to the Blackburn Flying School, Hendon, by September 1912.
   4. 50 hp Gnome School machine, cut-away wing roots, first flown at Filey March 1912.
   5. 50 hp Anzani No details.
   6. 50 hp Gnome Exhibition machine first flown 7 June 1912.

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

P.Lewis British Aircraft 1809-1914 (Putnam)

Blackburn Mercury Monoplanes

   Although his first essay at designing an aircraft was not an all-round success, Robert Blackburn was undeterred and set about achieving flight by a different approach. New premises were acquired in Balm Road in Leeds, and the construction of a lighter type of monoplane than the first was commenced in 1910. The Demoiselle lay-out utilized in the Heavy Type machine was abandoned. In appearance the Mercury was reminiscent of the successful Antoinette type, and also incorporated a fuselage of triangular section, a feature of all subsequent Blackburn monoplanes up to the 1914 L Biplane.
   Acquaintance with R. J. Isaacson, designer of the Manning Wardle Engine Company of Leeds, resulted in the decision to use the 40 h.p. Isaacson radial engine, a very unusual and original design in that it was of a stationary type at a time when the rotary form used by the Gnome was most popular. The Isaacson engine also employed pushrod-operated overhead valves and incorporated a 2 : 1 reduction gear drive to the propeller.
   It was hoped that the machine would fly at the August, 1910, meeting at Blackpool to which it was taken. However, difficulties with the engine prevented the Mercury from taking part, and it was not until March, 1911, that B. C. Hucks managed to take it into the air at Filey Sands. After reaching a height of 30 ft., and a speed of 30 m.p.h., the aircraft caught one wing-tip in the ground while turning and damaged the undercarriage. Following repair, Hucks used it subsequently to gain his Royal Aero Club Aviator's Certificate No. 91 at the same place on the following 30th May.
   As soon as the single-seat Mercury had proved itself, a two-seat version was constructed early in 1911 for use by Hucks at the Blackburn Flying School at Filey. It was on display at the 1911 Olympia Aero Show and was seen to have a wing of tapered form compared with the parallel chord used on the first Mercury. To avoid straining the wing structure through the warping control, the wings were pivoted about the rear spar. The controls for the flying surfaces consisted of handwheels, leaving the feet free for operating (he engine acceleration by a foot pedal, although a hand lever was used also for speed control of the 50 h.p. Isaacson radial. Ash was employed for most of the lattice girder framework, the forepart of the fuselage being wood covered. The strong undercarriage was made up from ash struts and incorporated rubber shock absorbers and steel springs on the axle.
   Two improved Mercurys were designed to compete in the Daily Mail Circuit of Britain race of July, 1911. One was for B. C. Hucks and the other for Conway Jenkins. Each was fitted with a 50 h.p. Gnome in a circular metal cowling. Neither achieved any success in the contest: Hucks damaged his machine on reaching Luton and had to retire, while Jenkins crashed at the starting-point at Brooklands. However, in August, 1911, Hucks took his Mercury on a very successful tour of the West of England, making two crossings of the Bristol Channel and demonstrating wireless telephony in September at Cardiff at 50 m.p.h. from 700 ft. in conjunction with H. Grindell Matthews on the ground. Early in 1912, Hucks's Mercury was at Shoreham in the hands of Lt. Walter Lawrence, 7th Essex Regiment, who intended to make a cross-Channel flight with the society hostess, Mrs. Leeming. On 23rd March, 1912, on its way to Dover, the machine was badly damaged when Lawrence overturned it at Eastbourne. The projected flight was abandoned and the Mercury was rebuilt for instruction and exhibition use at the Blackburn Flying School at its new home at Hendon, where it carried the number 33. Among the minor alterations made during reconstruction was the addition of a scuttle dash for greater comfort of the crew. Unified wheel control was fitted for the rudder, elevators and wing warping. The entire fuselage bracing was carried out with wood, to the exclusion of tie-wires, and the fore-part was aluminium covered. In April, 1913, Harold Blackburn flew No. 33 into third place in the Aero Show Trophy race at Hendon.
   Among other variants of the Mercury were at least two fitted with 60 h.p. Renault engines, one of which was ready at Filey in November, 1911, and was expected to lift three passengers. The machine took off fully-loaded in 30 yds., had an endurance of 4 hrs. and was flown in the moonlight at 1 a.m. by Hubert Oxley in December, 1911. On 6th December, Oxley and his passenger R. Weiss were killed at Filey when the machine crashed from 50 ft. before landing. The total of approximately eleven Mercury light monoplanes is believed to have included a version powered by a 50 h.p. Anzani engine.

SPECIFICATION

   Description: Single- and two-seat high-wing tractor monoplane. Wooden structure, fabric covered.
   Manufacturers: Blackburn Aeroplane Co., Balm Road, Leeds, Yorkshire.
   Power Plant: 40 h.p. Isaacson, 50 h.p. Isaacson, 50 h.p. Gnome, 60 h.p. Renault.
   Dimensions
   (50 h.p. Isaacson two-seater): Span, 38 ft. 4 in. Length, 33 ft. Wing area, 290 sq. ft.
   (50 h.p. Gnome single- and two-seater): Span, 36 ft. Length, 32 ft. Wing area, 220 sq. ft.
   Weights: Empty, about 800 lb.
   Price (40 h.p. Isaacson single-seater): ?550.

Журнал Flight

Flight, March 11, 1911

BRITISH NOTES OF THE WEEK.

The Blackburn Monoplane at Filey.

ALTHOUGH the machine was somewhat damaged in the end, very fair success was attained on Tuesday during some trials over Filey Sands with the Blackburn monoplane. With Mr. Hucks in the pilot's seat, the machine was run for a distance of three miles along the sand, just to see that everything was in order. Then, on the elevator-lever being moved, the monoplane took the air, and rising to a height of about 30 ft. headed for Filey Brigg, the speed being about 30 m.p.h. Unfortunately, in making a turn, the machine swooped, and one wing caught the ground, bringing the machine down, damaging the chassis.


Flight, March 25, 1911

AEROPLANES.

   Blackburn Aeroplane Co. - Blackburn monoplane "Mercury," passenger type. In general design, the machine is composed of a body, to which are attached the two sustaining planes and where also is the pilot's seat. At the front is the motor and tractor screw and at the rear the tail for stability, at the extremity of which are hinged the controlling planes for direction and altitude.
   The whole is supported by a landing chassis.
   The following are the characteristics of the "Mercury" :-
   Body. - The body is triangular in section and tapers backwards from that point where is fixed the pilot's seat, which occupies a position behind the passenger's seat, to the rear.
   The construction, which is throughout of specially selected English ash, is in the form of a lattice girder, the members of which are butted up to the three main beams in such a manner as to ensure, as much as possible, their working in compression. This method of construction gives great strength and elasticity.
   The front portion of the fuselage is covered with highly polished veneered wood, and the latter part with fabric, in order to reduce head resistance.
   Planes. - The main planes are trapezoidal in form.
   The two main spars on which the sections are built are of solid ash, grooved out along the neutral axis to form a channel section. In addition to these, lattice girder work, which is very strong, and, at the same time, light, runs the whole length of the planes, giving increased strength to counteract the upward and backward thrusts imparted to the planes whilst travelling through the air.
   The sections are cut out to their true form and built up with wooden cords, forming the ribs to which is attached the fabric. The inner ends of the main spars form the attachment to the fuselage, the rear attachment being pivoted in a manner which will permit of the warping of the planes without causing the slightest strain.
   Landing Chassis. - The fuselage is supported on a very strong chassis which is composed of two long skids connected to the body by ash struts and strongly braced up with high-tension steel wire.
   Each skid is borne by a pair of wheels, the axle of which is held down by strong elastic shock-absorbers.
   On the axle of the wheels are fitted steel springs which take any side thrust caused by the rough nature of the ground or a sideward landing. The whole arrangement allows for a deviation from the straight course.
   Tail. - The rear portion of the body carries the tail, formed of a horizontal and vertical plane.
   These are supported by vertical and horizontal ash beams, to which are also hinged the elevator and rudders. The whole is supported on a skid attached to the bottom of the vertical beam and carried up to the under portion of the fuselage.
   Control. - The "Blackburn" patented triple control has been designed with the object of effecting all the necessary movements with one control. The three movements can be operated independently or simultaneously by the hand-wheel, leaving the feet free for the control of the engine.
   The engine speed is controlled by a throttle lever, placed at the side of the pilot's seat, and also by a foot accelerator pedal operating in conjunction with but independent of the hand lever. By this means the throttle-lever can be set for a minimum or any desired engine speed, and thus, by depressing the foot-pedal the engine is instantly accelerated. When it is required to retard the speed of the engine, the accelerator pedal is released, but without any fear of stopping the engine, as it cannot retard below the setting of the throttle-lever.
   Motor. - This machine is fitted with a 50-h.p. 7-cyl., radial, "Isaacson" engine. Bore 90 mm. Stroke, 115 mm. Number of revolutions, 1,600 per min.
   Propeller. - The "Blackburn" propeller.
   Weight. - 800 lbs. approx.


Flight, May 27, 1911.

FROM THE BRITISH FLYING GROUNDS.

Filey School (Blackburn Aeroplane Co.)

ON Thursday last week, Mr. Hucks, after completing his flight to Scarborough, spent over two hours in the air, repeating over and over again the necessary tests required for the Royal Aero Club's certificate. In one of his flights he executed a pretty vol plane from a height of 1,300 ft., and landed perfectly without the slightest jar.
On this day arrangements had been made with the Aero Club officials to witness the official flights for the pilot's certificate. He accomplished the distance flights with the greatest ease, as he had repeatedly done the required tests day by day previously.
He rose at 12.22 1/2 p.m. and completed the first figure of eight at 12.24, the second at 12.25 1/2, the third at 12.27, the fourth at 12.28 1/2, the fifth and last to count at 12.29 1/2, the sixth being finished at 12.30 1/2. He did one or two extra turns, but the official figures given show how he decreased his time each round. During this time the machine, which answered perfectly to his every demand, attained a height of over 300 ft., from which he came gracefully down to the exact starting point.
It was then thought that Mr. Hucks had completed everything for his certificate, when a doubt arose as to whether two distinct flights were necessary, and therefore to make assurance doubly sure on this point, Mr. Hucks decided to go up again. He set off and completed the first circuit, and was in the act of turning in the second circuit when the propeller flew clean off the engine and continued spinning round till it touched the ground. Had the machine been making a straight course there is no doubt but that Mr. Hucks would have been able to plane down with safety, but owing to the severe angle he was turning at the moment, the machine came to the ground and was badly damaged. Fortunately, Mr. Hucks escaped without any severe injury. The cause of this accident was due to the breaking of the sleeve of the propeller, which was due to it seizing and getting overheated. It is expected that Mr. Hucks will soon be ready to fly again.
Throughout the week Mr. Weiss has been practising by making trial straight runs to enable him to steer the machine in a straight course. He has now practically mastered this, and will shortly make attempts at short flights.


Flight, August 5, 1911.

THE BLACKBURN MONOPLANE.

   AMONG the British firms early in the aeroplane industry, the Blackburn Co., of Leeds, is now achieving a success that is the reward of steady perseverance. Their machines have been flying particularly well lately over the Filey sands, and it is interesting, therefore, to publish at this moment the accompanying illustrations showing their general lines and constructive detail.
   Broadly speaking, the Blackburn monoplane must be classified as belonging to the Antoinette type, its dihedral double-surfaced wings, boat-like covered body, and general arrangements of the tail members being superficially similar to this prototype. In detail, however, the apparent similarity disappears to give place to marked originality of constructive work. A mere glance at the accompanying full page drawing is sufficient to indicate at least one decided departure from Antoinette practice in the use of an under-carriage of altogether different design. The Blackburn monoplane is supported on a Farman type wheel and skid combination, but the skids have a narrow track of only five feet and the body is supported above them by a very substantial multiple "A" frame, which gives great rigidity and strength to the fore part of the machine.
   The skids, it will be observed, are carried sufficiently far forward to protect the propeller, which is of unusually large diameter owing to the use of an Isaacson stationary radial engine, one of the features of which is, as our readers are aware, the combination of the engine with a half-speed reduction-gear for the propeller-drive. From the point of view of protecting the propeller, the utility of the strong "A" frame becomes still more apparent, for it will be noticed how little overhang there is to the toe of each skid.
   The body of the machine is triangular in section and tapers towards the tail aft of the pilot's seat. It is built throughout of ash in the form of an openwork lattice girder, the vertical and diagonal struts being carefully butted against the longitudinal booms so as to make a thoroughly sound job without the use of wire. When finished, the body is surfaced with fabric on the after part and with veneered wood in front.
   Ash spars are also used in the wings, and these are grooved to an I section so as to combine lightness with strength. The ribs are very carefully built about the spars, and a certain amount of lattice girder work is also introduced into the construction of the wing so as to increase its rigidity. The front main spars are rigidly fixed to the body, but those behind are hinged in order to facilitate wing warping.
   The control of the Blackburn monoplane is one of the special features of its design, a universal mechanism being employed which differs, however, from the usual types. Immediately in front of the pilot, who occupies a seat in line with the trailing edges of the wings, is a steering-wheel placed in a vertical plane on a longitudinal shaft. This shaft terminates in a universal-joint, the forward portion of which is itself mounted in bearings on a bracket that is attached to a hollow transverse-shaft carried in supports projecting above the body of the machine. This transverse-shaft is divided at the centre in order to accommodate the aforementioned bracket, which is itself cut away so as to give room for a small winding-drum that is attached to the forward extremities of the universally-jointed shaft.
   When the hand wheel is rotated, this winding drum operates a cord passing through the hollow transverse-shaft over pulleys to a lever that controls a longitudinal rock-shaft situated immediately under the body of the machine. From the forward end of this underneath rock-shaft other cords pass to the rear spars of the wings, for the purpose of warping. Turning the wheel is, therefore, employed for the purpose of balancing the machine by wing-warping.
   Between the hand-wheel and the universal-joint, the first-mentioned shaft carries a fixed collar from which radiate four wires. Two pass over pulleys mounted on the tops of the brackets that support the transverse rock-shaft. The other two are connected in such a way that an up and down movement of the wheel causes the transverse-shaft already mentioned to rock. On the transverse-shaft is a lever from the extremities of which wires pass to the elevator. Raising and lowering the hand-wheel is thus employed for controlling the attitude of the machine in flight by means of the elevator, which consists of a hinged extension to the fixed horizontal tail plane.
   When the hand-wheel is moved bodily sideways, the other wires, already described, operate the rudder, which consists of two triangular planes situated above and below the elevator. The special shape of these rudder planes is, of course, to enable the elevator to move up and down to the required extent.
   The tail portion of the machine is supported above the ground by a simple skid that is trussed by the rudder post. Similar skids may also be observed on the extremities of the main wings, where they act as fenders should the machine accidentally heel over while running along the ground.
   By no means the least interesting point in connection with the development of the Blackburn aeroplane is the fact that this Company have from the first been firm supporters of the Isaacson radial stationary engine. As our readers are already familiar with the features of this motor, it is, however, unnecessary to do more than merely refer to its three outstanding peculiarities, the first of which is that although radial the engine does not revolve; the second being that while stationary the engine is, nevertheless, air cooled, while the third feature is that, while the propeller is mounted concentrically about the crank-shaft it is, nevertheless, driven at half engine speed.


Flight, October 14, 1911.

THE BLACKBURN WARPING DEVICE.

   A CLEVER method of effecting wing warping is employed on the Blackburn monoplane, and is illustrated herewith. Whereas it is customary to carry merely one wire to the wing-tip for the purpose of flexion, while the middle portion of the rear-boom is left more or less to look after itself, Mr. Blackburn designs his warping mechanism so that the whole of the rear boom swings positively about its pivoted attachment to the main body. Three clips are arranged approximately equidistant along the rear wing spar, and from these clips stranded cables are led over pulleys fixed on the back of the landing skids and attached by means of steel plates and split-pins to different radii set off on a small pressed-steel rocker, illustrated in Fig. 1.
   The cable from the wing-tip, where there is naturally the greatest amount of flexion, is attached to the end of the rocker at a, and the cables from the two other clips are connected to points b and c on the rocker in such a way that the requisite amount of pull is given to each.
   The method of dealing with those wires that support the rear wing boom when the machine is stationary is also a departure from usual practice. It will be recalled that these wires are generally passed over pulleys or through tubes at the apex of the cabane. This, of course, introduces friction, and to eliminate this Mr. Blackburn utilises the device illustrated in Fig. 2. The wires from the rear spar are passed through and securely brazed to a ribbon steel pendulum, which swings about a bolt at the top of the stout ash mast. They are connected so that the wire that undergoes the most movement passes through that part of the pendulum where the amplitude of swing is greatest, i.e., the end, and vice versa.


BRITISH NOTES OF THE WEEK.

Mr. B. C. Hucks Demonstrates at Cheltenham

   AFTER his exhibition flights at Cardiff, Mr. Hucks' next point was Cheltenham, where he terminated his recent aviation tour in the west. Some excellent flights were made on the 5 th and 7 th inst., a special exhibition being given on the Gnome-engined Blackburn monoplane for the benefit of the Cheltenham collegians, who showed the greatest enthusiasm for the treat afforded them. On Saturday, whilst flying at a height of somewhere near 1,000 ft., Mr. Hucks' petrol gave out, but this in no way disconcerted him, as he made a graceful vol plane landing without damage in a neighbouring field to the Whaddon Farm, where his hangar was erected.


Flight, February 24, 1912.

AIR EDDIES.

   The next aspirant for cross-Channel honours is Lieut. Walter Lawrence, of the 7th Essex Regiment, who is at the Shoreham Aerodrome awaiting an .opportunity to effect the crossing on his Blackburn monoplane, taking with him Mrs. Leeming, a well known Society hostess, as passenger. The machine on which he intends to accomplish the flight is the identical monoplane with which Bentfield Hucks carried out his "missionary" work in the West Country at the close of last season. Lieut. Lawrence is, by the way, the first Territorial officer to master the intricacies of both monoplane and biplane.


Flight, March 2, 1912.

AIR EDDIES.

   Talking with Mr. R. Blackburn the other day, I learnt that, of the new Blackburn Military monoplanes now in the process of construction at his Leeds works, there is not a single component part that is not capable, under actual test, to withstand a stress of at least ten times that which it is likely to be called upon to bear under normal flying conditions. The Blackburn is still doing good work with Lieut. Spencer Grey at Eastchurch, and Lieut. Laurence at Shoreham. During last week the latter flew over to Eastbourne to pay a visit to Mr. F. B. Fowler, of the Eastbourne Aviation Co., completing a flight of 28 miles within the half hour, in spite of a head wind.
   On Thursday last he had intentions of flying on to Dover, and it is more than likely that his projected Channel crossing may be a fait accompli by the time these lines appear in print.


Flight, November 16, 1912.

THE BLACKBURN SCHOOL MONOPLANE.

   FOR a long time the Blackburn Aeroplane Co. has been working steadily and scientifically up at Leeds and Filey, where they have produced the machines with which they have from time to time made so many excellent flights. It is only comparatively recently, however, that they have established a London centre at the Hendon Aerodrome, and although this may seem to make the Blackburn monoplane somewhat more in evidence than hitherto it has been to Londoners, it will not necessarily bring it more to the fore with readers of FLIGHT who have the advantage of being equally in touch with all centres of aviation. It is a British-built machine of British origin and as such has particular claim on the attention of most of our readers, some of the points of design being of special merit.
   And, as a complete aeroplane it is well worthy of study, the more so, perhaps, because it is exceedingly simple, and at a first glance represents all that one expects to see as characteristic of monoplane construction. As the eye looks longer at its slim lines, however, the position of the engine well out in front of the wings strikes one as a departure from the conventional, and as one goes closer little points in the chassis construction attract the attention, and notably the method of supporting the wings from a mast, which rises from the floor of the body and which is strutted then by diagonal members of ash to the main chassis skid. It only needs a glance at the elevation of the machine, which is the subject of one of our full page illustrations, to see very clearly that the designer is seeking to overcome the inherent difficulty of providing external drift wires in monoplane construction. By balancing his machine with the engine well forward he has been able to arrange a point of attachment of the wing wires to the chassis skid, which is well forward of the position that ordinarily would be occupied by the engine, and therefore within the zone of interference by the propeller.
   It is unnecessary and also to small purpose to go through the construction of the Blackburn monoplane piece by piece; much of what is interesting therein, but not all that is deserving of notice, forms the subject of our detail sketches which convey to the eye at a glance far more than can be communicated to the brain through a column of print. It is only of importance to draw attention to one or two matters that might otherwise escape notice, as for instance that the triangular section lattice girder backbone is trussed entirely with ash, no wire being used in its construction. The forward part of the fuselage, forming the body, is surfaced with aluminium and the after part with fabric. Tubular steel main spars filled with timber are now used as the principal wing members, and the details of their attachment to the body are well shown in the sketches. The rear spar is hinged, and when the wings are warped the ribs swivel around it so as to impose no twisting strain. The ribs are made of cotton wood and are prevented from sliding along the spars by the intervention of ash distance pieces. The wing surfacing consists of Irish linen treated with Emaillite. The control is a very interesting feature of Blackburn design, but being one with which all readers of FLIGHT ought to be very well familiar by now, we need only draw attention to the sketch in which this detail is illustrated. A single wheel serves for steering the rudder, while the elevator is operated by a vertical movement of the inclined steering column; moving the same sideways, warps the wings. On the school machine, from which these illustrations were made, the power plant consists of a 50 h.p. Gnome engine driving a Blackburn propeller.