The Gloster F.9/37, also known as the Gloster G.39, was a British twin-engined design from the

Gloster Aircraft Company The Gloster Aircraft Company was a British aircraft manufacturer from 1917 to 1963. Founded as the Gloucestershire Aircraft Company Limited during the First World War, with the aircraft construction activities of H H Martyn & Co Ltd of Chelte ...

for a cannon-armed

heavy fighter A heavy fighter is a historic category of fighter aircraft produced in the 1930s and 1940s, designed to carry heavier weapons, and/or operate at longer ranges than light fighter aircraft. To achieve performance, most heavy fighters were twin-eng ...

to serve with the

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...

, planned before the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

. The F.9/37 was rejected in favour of other designs. A development of the F.9/37 as a

night fighter A night fighter (also known as all-weather fighter or all-weather interceptor for a period of time after the Second World War) is a fighter aircraft adapted for use at night or in other times of bad visibility. Night fighters began to be used i ...

, for a new Air Ministry Specifications F.29/40 – known unofficially as the Gloster Reaper – was dropped so that Gloster could concentrate on existing work and on the nascent British jet projects.

Design and development

Gloster had designed a twin-engined turret-fighter for specification F.34/35 but the single-engined

Boulton Paul Defiant The Boulton Paul Defiant is a British interceptor aircraft that served with the Royal Air Force (RAF) during World War II. The Defiant was designed and built by Boulton Paul Aircraft as a "turret fighter", without any fixed forward-firing guns ...

for F.9/35 was seen to cover both requirements and the F.34/35 design dropped. Less than two years later, F.9/37 for a "twin-engined single-seat fighter with fixed armament" was issued. The F.9/37 was designed under the direction of George Carter, his first for Gloster, to F.9/37 (hence the name) as a single-seat fighter carrying an armament of four 0.303 in (7.7 mm) Browning machine guns and two 20 mm Hispano cannon in the nose. Intended for dispersed production by semi-skilled labour, the structure broke down into sub-assemblies. A prototype ( military serial ''L7999'') with 1,060 hp

Bristol Taurus The Taurus is a British 14-cylinder two-row radial aircraft engine, produced by the Bristol Engine Company starting in 1936. The Taurus was developed by adding cylinders to the existing single-row Aquila design and transforming it into a twin ...

T-S(a) radial engines flew on 3 April 1939 and demonstrated excellent performance, its maximum speed of being the best recorded by a British fighter at the time. Test flights revealed that the prototype was very manoeuvrable and "a delight to fly". After being badly damaged in a landing accident in July 1939, it was re-engined with 900 hp Taurus T-S(a)-IIIs in 1940, which reduced its performance. A second prototype (''L8002'') with 880 hp

Rolls-Royce Peregrine The Rolls-Royce Peregrine was a , liquid-cooled V-12 aero engine designed and built by the British manufacturer Rolls-Royce in the late 1930s. It was essentially the ultimate development of the company's Kestrel engine, which had seen wides ...

I liquid-cooled, inline engines flew on 22 February 1940; it proved capable of at .

F.18/40 and F.29/40

Specification F.18/40, for a specialist

, with nose- and turret-mounted guns, led to Gloster submitting a design based on the F.9/37, fitted with

Rolls-Royce Merlin The Rolls-Royce Merlin is a British liquid-cooled V-12 piston aero engine of 27-litres (1,650 cu in) capacity. Rolls-Royce designed the engine and first ran it in 1933 as a private venture. Initially known as the PV-12, it was late ...

engines, a dorsal four-gun turret and Airborne Interception (AI)

radar Radar is a detection system that uses radio waves to determine the distance ('' ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, we ...

. This received support from the Air Staff who saw it as superior to the Bristol Beaufighter and the

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of State ...

ordered one of the F.9/37 prototypes to be converted to the new specification as F.29/40. Unofficially known as the Gloster Reaper, it inherited the admirable handling characteristics of the F.9/37 and despite being judged superior to other designs, including turreted variants of the Beaufighter and de Havilland Mosquito, the Reaper was terminated in May 1941, for Gloster to concentrate on other work, especially the Gloster E.28/39 jet aircraft.

Specifications (''L7999'': Taurus engine)

Footnotes

Bibliography

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External links

Gloster F.9/37
– British Aircraft Directory

{{DEFAULTSORT:Gloster F.9 37 F.9 37 1930s British fighter aircraft Cancelled military aircraft projects of the United Kingdom Turret fighters Low-wing aircraft Aircraft first flown in 1939 Twin piston-engined tractor aircraft