The Bristol Type 107 Bullpup was a British fighter aircraft built in the 1920s. It was not selected for squadron service and only the single

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and software programming. A prototype is generally used to ...

was built

Background

The design of the Bullpup was an outcome of a series of design studies for a fighter undertaken by

Frank Barnwell Captain Frank Sowter Barnwell OBE AFC FRAeS BSc (23 November 1880 – 2 August 1938) was a Scottish aeronautical engineer. With his elder brother Harold, he built the first successful powered aircraft made in Scotland and later went on to a c ...

during the 1920s. In 1924 Barnwell had started work on a fighter powered by the Rolls-Royce Falcon to meet the requirements of specification F.17/24. This project was shelved since Bristol preferred to use their own engine designs, but was revived in 1926 when Barnwell started work on a design, designated the Bristol 102, to meet either F.9/26 for a day-and-night fighter or N.21/26 for a shipborne fighter. A subsequent proposal, designated Type 105 was for another aircraft to meet F.9/26, powered by the Mercury engine then under development at Bristol. These proposals were sufficient for a pair of mockups to be constructed for inspection by the Air Ministry in February 1927. The two aircraft were similar in design, the interceptor to specification F.17/24 design being slightly smaller and lighter and not equipped with radio. As a result, Bristol was asked to revise the design so that it met a later interceptor specification, F.20/27. Subsequently, a prototype was ordered for evaluation, but the other design did not gain official backing. Nevertheless, Bristol considered it promising enough to build a prototype to be entered for the F.9/26 trials as a private venture, powered by a

Bristol Jupiter The Bristol Jupiter was a British nine-cylinder single-row piston radial engine built by the Bristol Aeroplane Company. Originally designed late in World War I and known as the Cosmos Jupiter, a lengthy series of upgrades and developments turn ...

because the supply of Mercurys was expected to be limited. This became the

Bristol Bulldog The Bristol Bulldog is a British Royal Air Force single-seat biplane fighter designed during the 1920s by the Bristol Aeroplane Company. More than 400 Bulldogs were produced for the RAF and overseas customers, and it was one of the most fam ...

Design and development

The Type 107 was an unequal span single bay biplane powered by a 480 hp (360 kW)

Bristol Mercury The Bristol Mercury is a British nine-cylinder, air-cooled, single-row, piston radial engine. Designed by Roy Fedden of the Bristol Aeroplane Company it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from ...

air-cooled radial engine driving a two-bladed propeller. The structure was all-metal with a fabric covering, using members built up from rolled high-tensile steel strips riveted together. In order to optimise the pilot's field of view there was large semi-circular cutout in the trailing edge of the upper wing and the inboard section of the lower wing was of reduced chord.

Frise aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

s were fitted to the top wing only. It was armed with a pair of 0.303 in (7.7 mm) Lewis guns mounted on either side of the cockpit. The prototype first flew on 28 April 1928, powered by a

engine since a flight-ready Mercury was not yet available, and the aircraft was not delivered to Martlesham Heath for evaluation until March 1929. The Bullpup prototype was subsequently fitted with a Jupiter F type head with twin compensator rods for the penthouse heads. Trials with this engine were carried out at Martlesham in 1929."Bristol Bullpup."
''The Transport Archive''. Retrieved: 1 August 2008.

Operational history

Performance at the F.20/27 competition held in 1929 was respectable but in the event none of the competitors was to enter service, the requirement eventually being met by the

Hawker Fury The Hawker Fury is a British biplane fighter aircraft used by the Royal Air Force in the 1930s. It was a fast, agile aircraft, and the first interceptor in RAF service capable of speed higher than 200 mph (321 kmh). It was the fighter co ...

, a

Rolls-Royce Kestrel The Kestrel or type F is a 21 litre (1,300 in³) 700 horsepower (520 kW) class V-12 aircraft engine from Rolls-Royce, their first cast-block engine and the pattern for most of their future piston-engine designs. Used during the interwar ...

-engined development of the Hawker F.20/27 contender. The prototype was used as an engine test aircraft until it was scrapped in 1935 at the end of the

Bristol Aquila The Aquila was a nine-cylinder single-row radial aircraft engine designed by the Bristol Engine Company starting in 1934. A sleeve valve engine, its basic design was developed from the Bristol Perseus. The Aquila was never used in production, ...

development programme.

Specifications

References

Notes

Bibliography

* Barnes, C.H. ''Bristol Aircraft Since 1910''. London: Putnam, 1964. . * Barnes, C.H. ''Bristol Aircraft since 1910''. London: Putnam, 1988. . * Green, William and Gordon Swanborough. ''The Complete Book of Fighters''. Godalming, UK: Salamander, 2001. . {{Bristol aircraft Biplanes Single-engined tractor aircraft 1920s British fighter aircraft

Bullpup A bullpup firearm is one with its firing grip located in front of the breech of the weapon, instead of behind it. This creates a weapon with a shorter overall length for a given barrel length, and one that is often lighter, more compact, conce ...