In 1919 Frank Barnwell took the flying surfaces from a Badger – a proposed development of the F2B fighter – and made up a cheap slab-sided fuselage for experimental work. The whole thing cost £250 to build and was known as the Badger X, (and unofficially as Barnwell’s weekender).
It became the first aircraft to appear on the UK civil register as G-EABU on 30 May, by which time Barnwell had turned it over on the golf course adjacent to the Filton airfield. He was left unharmed but angry, hanging from the straps, and he got even angrier when someone released his straps before getting hold of him, and he landed on his head!
In 1911, George Challenger and Archibald Low designed the single seat Bristol Monoplane, powered by a 50 hp Gnôme rotary engine. Two of these machines (No. 35 and No. 36) were built, and exhibited at the Olympia Aero Show in February and in St. Petersburg in March. The monoplane tried at Larkhill, where it was damaged during taxi tests. It was not rebuilt, due to the more promising Bristol-Prier monoplane then under construction.
The last of the ‘Bristol’ aircraft was the purely research aeroplane, the Type 221. With the B.188, they furnished valuable information on the structural and aerodynamic problems associated with supersonic flight. The Type 221, first flown was on May 1, 1964, was a modified version of the record breaking Fairey Delta 2 and used to investigate the handling and control characteristics of the slender ogival wing, which was again to feature in the Concorde.
Engine: 1 x 5000kg Wingspan: 7.62 m / 25 ft 0 in Length: 17.55 m / 57 ft 7 in Height: 3.96 m / 12 ft 12 in Wing area: 46.82 sq.m / 503.97 sq ft Max. speed: 1707 km/h / 1061 mph Crew: 1
In the mid 1950s Bristol Aircraft Ltd began work on a turbine-powered helicopter using a B.171 Syvamore Mk 3 with an increased fin area. Under the name Bristol 203 it was to be an 11-seat machine and parts from the incomplete 179th and 180th Sycamore airframes were used in the prototype machine. This project was abandoned when the company was taken over by Westland, although some of its finer points were later incorporated in the Lynx.
Captain Frank Barnwell designed the MF as an all-metal parasol-wing monoplane that could be flown as the MFA single-seat fighter or MFB two-seat reconnaissance plane. The latter had an extra fuselage section behind the cockpit for the gunner’s position and, below this on a short cabane arrangement, a cantilever second wing. In April 1921 the Air Ministry ordered three prototypes with wooden wings. Bristol proposed the name Pegasus, but this did not conform with current British practise and the two MFAs became Bullfinch Mk Is while the sole MFB became the two-seat Bullfinch Mk II. By March 1922, when the name Bullfinch was officially adopted, the decision had been taken to complete two of the prototypes as single-seaters, these being delivered in April 1923. Armed with two 7.7mm Vickers machine guns, the Bullfinch single-seaters were flown experimentally by the RAF and were found to offer a relatively good performance on the 425hp of a Bristol Jupiter III radial, but no production order was forthcoming. The Mk II was first flown on 15 February 1924 and delivered in March 1924. The Bullfinch II differed from the single-seat model primarily in having a 91.4cm section housing a self-contained gunner’s cockpit inserted in the fuselage immediately aft of the pilot’s cockpit and beneath which was attached a cantilever lower wing, the resultant shift of the centre of pressure compensating for the change in the CG. The only other change consisted of the repositioning of the main undercarriage members farther aft. The rear cockpit was fitted with a Scarff-mounted 7.7mm Lewis gun, and structural weight was increased by 145kg. The 425hp Jupiter III engine was insufficiently powerful to cater for the additional 400kg of the two-seater in fully loaded condition and the performance of the Bullfinch II suffered. Both variants were fully evaluated, but no orders followed.
Bullfinch II
Principal versions – Bullfinch Mk I (single-seat fighter prototype) and Bullfinch Mk II (two-seat reconnaissance prototype).
Bullfinch Mk.I Engine: one 450-hp (336-kW) Bristol Jupiter III radial Maximum speed 135 mph (217 km/h) at 15,000 ft (4,570 m) Srvice ceiling 22,000 ft (6,705 m) Endurance 4 hours 0 minutes. Empty weight 2,175 lb (987 kg) Maximum take-off weight 3.205 lb (1,454 kg). Wing span 38 ft 5 in (11.71 m) Length 24 ft 5 in (7.44 m) Height 10 ft 9 in (3.27 m) Wing area 267.0 sq ft (24.80 sq.m). Armament: two 0.303-in (7.7-mm) fixed machine guns.
Bullfinch Mk.II Engine: 425hp Jupiter III Take-off weight: 1854 kg / 4087 lb Empty weight: 1132 kg / 2496 lb Wingspan: 11.71 m / 38 ft 5 in Length: 8.38 m / 27 ft 6 in Height: 3.28 m / 10 ft 9 in Wing area: 36.32 sq.m / 390.94 sq ft Max. speed: 193 km/h / 120 mph
A helicopter department was set up in 1945 as part of the aircraft division at Filton, and Austrian-born Raoul Hafner, who had devoted himself to rotary wing research in the thirties, moved to England before the Second World War and took charge in 1944. Design studies, under Raoul Hafner, were started in June 1944 and, since no suitable British engine was available at that time, the two Mk.1 prototypes (VL958 and VL963) were built with 450hp Pratt & Whitney 11-985 Wasp Junior radial engines. These were 2-seaters, conforming to Ministry of Supply specification E.20/45. The design featured a light alloy cabin section and a stressed-skin tailboom attached to a central engine and gearbox mounting, the rotor head being fitted with three wooden monocoque blades. The crankshaft lay horizontally, with power transmitted to the vertical driveshaft through a gearbox. The three rotor blades were made of wood with leading edges in hardwood. After component testing, ground running of the completed airframe began on 9 May 1947, the first flight (VL958) was made by H. A. Marsh on 27 July 1947.
The second aircraft (VL963) joined the test programme in February 1948 and on 25 April 1949, to facilitate its flight to the Paris Salon, it became the first British helicopter to be granted a civil certificate of airworthiness. The third airframe appeared in the static park at the 1948 SBAC exhibition at Famborough. This was followed by the first flight on 3 September 1949 of the one and only Mk.2, built as a 4-seater to specification E.34/46 and powered by a 550hp Alvis Leonides 71 LE 21 HM piston engine in a horizontal position with the crankshaft running vertically. This eliminated the lower gearbox which not only saved weight but made the engine more accessible for checking and repairs, and increased the seating from two to five. It was of metal construction with a three-blade main rotor and was designed as an air taxi (four-five seats) and for military tasks such as air observation and casualty evacuation. This aircraft formed the basis for the first production series, although numerous detail modifications were made to individual machines in these batches, some becoming standard on later production aircraft. Seating was increased to six. A second take-off attempt ended abruptly when the rotor disintegrated. With a strengthened rotor, development flying was resumed while work continued on the assembly of 15 production Mk 3s with a smaller Alvis Leonides 73 engine. Airframe changes included a shortened nose and an 0.20m increase in cabin width to accommodate three passengers on the rear seat; in order to maintain essential systems in the event of engine failure, and the accessory drive was transferred from the engine to rotor gearbox. The Sycamore had a simple auto-throttle which the pilot could override.
The Type 171 was manufactured at Filton and Weston-super-Mare.
Two Mk 3A were bought by British European Airways. They had a slightly superior performance to the Mk3 and greater baggage capacity, with a freight hold behind the engine bay. BEA began an experimental service with these helicopters between Eastleigh and Heathrow airport in 1954, which lasted for about two years.
The first two production batches, totalling twenty-five aircraft, included one HC Mk.10 ambulance for evaluation by the Army Air Corps; four HC Mk.11’s for Army communications work; four HR Mk.12’s for RAF search and rescue duties, evaluated by Coastal Command; and two winch-equipped HR Mk.13’s for similar trials with Fighter Command. These were collectively to Mk.3 production standard, with 520hp Leonides 73 engines. Two Mk.3A’s with improved performance, a shorter nose and extra baggage space behind the engine bay, were completed for British European Airways. Of the remaining dozen machines, five were to Mk.4 standard, also with Leonides 173 engines and having four cabin doors; these were built for the Royal Australian Navy (three HR Mk.50), Royal Australian Air Force (one) and RAF (one HR Mk.14). All of these were completed to Mk.3 standard with a Leonides 173 engine. The remaining seven aircraft were a mixture of Mk.3 and Mk.4 reserved for military trials or civil demonstration.
The 1950 Mk.4 with four access doors, a longer-stroke landing gear, a bigger baggage compartment and an hydraulic winch and the pilot’s position moved from port to starboard. This was primarily intended for search and rescue and air ambulance duties, and was supplied to the RAF (two HR.13s and 80+ HR.14), Belgian Air Force (three Mk.14B), Royal Australian Navy (three HR.50 & seven HC.51, equipped with winches for air-sea rescue duties, initially with No. 275 Squadron) and West German Government (50 Mk.52). No. 275 Squadron, RAF. received its first helicopter on 13 April 1953. Sycamores also operated in the light assault and reconnaissance roles in Malaya, Cyprus and Borneo, joining No.194 Squadron in Malaya in 1954 and No.284 in Cyprus late in 1956. In August 1955 a 171 took part in the first British air-to-ground television transmission involving the use of a helicopter. The Bristol Type 171 Sycamore Mk.4 was the final production version of this machine. 178 examples of which had been completed when the last was delivered in 1959. Of these 50 were built in 1957-1959 for the Federal Germany as the Sycamore Mk.52, most serving with the Luftwaffe but 4 being delivered to the Navy, joined later by a further four from the Luftwaffe stocks. The German Sycamore Mk.52 helicopters were withdrawn from service in 1972-1973. In the mid 1950s Bristol Aircraft Ltd began work on a turbine-powered helicopter using a Mk 3 with an increased fin area. Under the name Bristol 203 it was to be an 11-seat machine and parts from the incomplete 179th and 180th Sycamore airframes were used in the prototype machine. This project was abandoned when the company was taken over by Westland, although some of its finer points were later incorporated in the Lynx.
Mk.2 Engine: 550hp Alvis Leonides 71 LE 21 HM Main rotor: three-blade seats: 4-5.
Mk.3 Engine: 520hp Leonides 73 Length: 46.161 ft / 14.07 m Rotor diameter: 48 ft 6.75 in / 14.81 m Max take off weight: 5600.7 lb / 2540.0 kg Max. speed: 93 kt / 173 km/h Range: 232 nm / 430 km Crew: 2+3
Mk.3A Engine: 520hp Leonides 73
Mk.4 Engine: Leonides 73, 520 hp Cabin doors: 4 Fuselage length: 46 ft. 2in. Loaded weight: 5,400 lb. Max. speed: 141 m.p.h. Ceiling: 15,500 ft. Typical range: 268 miles at 92 m.p.h. Seats: 4-5
HR.13 Engine: 1 x Alvis Leonides 73 radial, 410kW Rotors: 3-blade main; 3-blade tail. Rotor diameter: 48 ft. 6.75 in. Fuselage length: 46 ft. 2in. Loaded weight: 5,400 lb. Max. speed: 141 m.p.h. Ceiling: 15,500 ft. Typical range: 268 miles at 92 m.p.h. Seats: 4-5
HR.14 Engine: 1 x Alvis Leonides 73 radial, 410kW Main rotor diameter: 14.81m Rotors: 3-blade main; 3-blade tail. Length with rotor blades folded: 14.07m Height: 3.71m Max take-off weight: 2540kg Empty weight: 1728kg Loaded weight: 5,400 lb. Max speed: 204km/h Cruising speed: 169km/h Ceiling: 15,500 ft. Endurance: 3h Typical range: 268 miles at 92 m.p.h. Seats: 4-5
Bristol Sycamore HR 50/51 (RAAF) Ordered: 1952 Number purchased: 13 First delivered: 1953 Last delivered: 1961 Engine: One 520 hp Alvis Leonides Mk72 7 cylinder radial Rotor diameter: 48 ft 6.75 in Rotors: 3-blade main; 3-blade tail. Loaded Weight 5,600 lb Fuselage length: 46 ft. 2in. Height: 12 ft 2 in Initial Rate of Climb: 1,300 ft/min Ceiling: 4,000 ft Speed: 127 mph (max sea level), 91 mph (cruising) Range: 238 miles Armament: Nil Seats: 4-5 Crew: 2
Experience: Hal Jowers Back in 1968, I was hired by Associated Helicopters in Bankstown, NSW to ferry their one flyable, of 5-hulls & a hanger-full of spare parts they had bought surplus at the time, up to Port Keats Mission (about 200nm S.W. of Darwin) and work a mineral exploration contract.
The ole Sycamore was a more-than-interesting bird – to say the least! With that short-arm collective (+/- 15-inches fulcrum to end) / rt. angle throttle and direct NO hydrolic-assist linkage to the swash-plate: it was like physically lifting the bird WITH ONE ARM!!! … Add to that; a fully-castering nose gear and a 40-gal. liquid ballast system that had to be transferred during lift-off, so extra collective friction was necessary to hold it while reaching for the transfer-pump handle – otherwise; you were instantly back on the ground with a much bigger, LIFE-FULL OF GROUND RESONANCE problem to handle!!! … Albeit; once you had her in the air, all you had to be concerned with was the sporadic – no plausible answer why – 0.5 – 1.5 second engine STOPS that gave your heart its EXTRA exercise for the day.
Having acquired some 85-hours flt.time in the course of that experience; upon return to Sydney I was fortunate to be in conversation with some old RAN Sycamore drivers who expressed no small amount of chagrin that I had been so successful, as to still be alive to enjoy that moment with them. I allowed as how My Holy Spirit keeper obviously had other things for Me to do, before He punches My “ticket”. … All of that was at +/- 2,200, of the final 13,420 flt.hrs. He has blessed Me with. … God Speed!!!
Embodying the lessons learned from the Type 133, the Type 146 was a single-seat eight-gun all-metal fighter of monocoque construction with stressed duralumin skinning. Intended to meet the requirements of Specification F.5/34, the Type 146 was designed for a fully supercharged Bristol Perseus radial of 835hp, but the sole prototype completed was fitted with an 840hp Mercury IX owing to the non-availability of the intended power plant. Armament comprised four 7.7mm Browning machine guns in each wing. Delayed in completion through its low development priority, the Type 146 was finally flown on 11 February 1938, but was already out-dated by the Merlin-engined Hurricane and Spitfire. After trials at Martlesham Heath, it was returned to the manufacturer to participate in a local RAF display, where it collided with a display set-piece while landing and was scrapped forthwith.
Engine: Bristol Perseus, 835hp/622kW. Take-off weight: 2086 kg / 4599 lb Empty weight: 1489 kg / 3283 lb Wingspan: 11.89 m / 39 ft 0 in Length: 8.23 m / 27 ft 0 in Height: 3.15 m / 10 ft 4 in Wing area: 20.44 sq.m / 220.01 sq ft Max. speed: 462 km/h / 287 mph
In the 1920s and 30s Bristol was closely associated with attempts on the world altitude record. During the ten years spanning 1928 1938 the record changed hands nine times and on six of these occasions the aircraft was powered by Bristol engines.
The Air Ministry ordered the Type 138 as a high altitude research aircraft to specification 2/34, calling for an aircraft capable of reaching 50,000ft.
Twice, in 1936 and 1937, the special Bristol Type 138 high altitude monoplane captured the record for Britain with heights of 49,967ft (15,230m) and 53,937ft (16,640m) (June 1937). It didn’t last as 18 months later this was broken by a Caproni 161bis which reached 56,000ft.
The 138A, powered by a 372.6kW Bristol Pegasus P.E.6S radial engine and flown by Sqn Ldr F. R. D. Swain, achieved a height record of 15.223m on 28 September 1936. On 30 June 1937 it raised the record to 16.440m/52,937 ft at the hands of Flt Lt M. J. Adam. The flight lasting 2 hr 15 min.
Flt.Lt. M.J. Adams after the 53,937 ft altitude record
Bristol 138A Engine: 1 x 500hp Bristol Pegasus P.E.6S Take-off weight: 2411 kg / 5315 lb Empty weight: 1994 kg / 4396 lb Wingspan: 20.12 m / 66 ft 0 in Length: 13.41 m / 43 ft 12 in Height: 3.12 m / 10 ft 3 in Wing area: 52.77 sq.m / 568.01 sq ft Max. speed: 198 km/h / 123 mph Ceiling: 16459 m / 54000 ft
Another private venture design for the F.7/30 competition, the Type 133 single-seat fighter featured a forward fuselage of girder-type construction, a monocoque rear fuselage and Alclad stressed skinning. Powered by a Bristol Mercury VIS.2 rated at 620hp for take-off and carrying an armament of two synchronised 7.7mm Vickers guns in the fuselage and a Lewis gun of similar calibre mounted above each mainwheel housing, the Type 133 flew for the first time on 8 June 1934. After completing a considerable amount of flying, on 8 March 1935 the prototype got into a flat spin and the engine stopped, the pilot baling out and the aircraft being destroyed. No further development was undertaken.
Engine: Bristol Mercury VIS.2, 620hp Take-off weight: 2149 kg / 4738 lb Empty weight: 1053 kg / 2321 lb Wingspan: 11.89 m / 39 ft 0 in Length: 8.53 m / 27 ft 12 in Height: 2.97 m / 9 ft 9 in Wing area: 22.95 sq.m / 247.03 sq ft Max. speed: 418 km/h / 260 mph Armament: 2 x 7.7mm Vickers guns, 1 x Lewis gun
The Type 123 was built as a private venture to meet the requirements of Specification F.7/30, a 695hp Rolls- Royce Goshawk III steam-cooled engine being provided by the Air Ministry. Of high-tensile steel construction with fabric-covered wings, rear fuselage and tail assembly, the Type 123 carried an armament of four fuselage-mounted 7.7mm Vickers machine guns, and was first flown on 12 June 1934, having been delayed by difficulties with the engine cooling system. Subsequently the Type 123 was found to suffer from lateral instability at high speed and further development was abandoned.
Engine: 695hp Rolls- Royce Goshawk III steam-cooled Take-off weight: 2149 kg / 4738 lb Empty weight: 1497 kg / 3300 lb Wingspan: 9.02 m / 29 ft 7 in Length: 7.67 m / 25 ft 2 in Height: 2.89 m / 9 ft 6 in Wing area: 23.04 sq.m / 248.00 sq ft Max. speed: 378 km/h / 235 mph
