The Bristol Scout E and F were a

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

single-seat biplane fighters built in 1916 to use newer and more powerful engines. It was initially powered by the Sunbeam Arab, but the third prototype was used as a testbed for the Cosmos Mercury, marking the start of

Roy Fedden Sir Alfred Hubert Roy Fedden MBE, FRAeS (6 June 1885 – 21 November 1973) was an engineer who designed most of Bristol Engine Company's successful piston aircraft engine designs. Early life Fedden was born in the Bristol area to fairly weal ...

's association with the Bristol Aeroplane Company. The

Armistice An armistice is a formal agreement of warring parties to stop fighting. It is not necessarily the end of a war, as it may constitute only a cessation of hostilities while an attempt is made to negotiate a lasting peace. It is derived from the ...

ended hopes of production.

Development

By the end of 1916 there was a shortage of suitably powerful engines for single-seat fighters needed for air superiority. One of the few available was the Hispano-Suiza 8, but it was unreliable and production was being absorbed by the need to power the Royal Aircraft Factory S.E.5A that was entering service.

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 ...

of the Bristol Aeroplane Company designed a single-seat biplane, called the Scout E, around a proposed ten-cylinder water-cooled radial engine designed by Harry Ricardo and

Frank Halford Major Frank Bernard Halford CBE FRAeS (7 March 1894 – 16 April 1955) was an English aircraft engine designer. He is best known for the series of de Havilland Gipsy engines, widely used by light aircraft in the 1920s and 30s. Career Educat ...

, but this failed to materialise and another powerplant was sought. The Company gained an

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 ...

contract for six aircraft and was promised some Hispano-Suiza V8s, but by June 1917 these had been replaced by Sunbeam Arab radials. With the Arab engine the design was redesignated the Scout F. The Scout F was a

single-bay A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a ...

biplane with staggered unequal-span wings with straight edges and rounded tips. Ailerons were carried only on the upper planes and there were smooth cutouts in both to improve the view from the open cockpit, placed just behind the trailing edge. The tail was conventional, with unbalanced control surfaces. The Scout F had a fuselage-mounted single-axle main undercarriage forward of the lower wing, plus a tailskid. The water-cooled V-8 Arab engine allowed a smooth and quite short installation, ending in a two-blade propeller and conical spinner. There was a small bulge on top of the cowling for the coolant header tank and the radiator was placed in a tunnel fairing between the undercarriage legs, with a pair of shutters for coolant temperature control. Persistent vibrations dogged the Arab and a decision was made to use it only in the first two Scout Fs, the first of which first flew in March 1918. It was fast, achieving 138 mph (222 km/h) at sea level, and could climb to 10,000 ft (3,050 m) in 9.5 min. The second was flown by experienced pilots at the

Central Flying School The Central Flying School (CFS) is the Royal Air Force's primary institution for the training of military flying instructors. Established in 1912 at the Upavon Aerodrome, it is the longest existing flying training school. The school was based at ...

, amongst them Oliver Stuart who judged it a better aerobatic airplane than the SE5a. Bristol Scout F (Mercury)

At this point Barnwell was approached by Roy Fedden of the

Cosmos Engineering company Cosmos Engineering was a company that manufactured aero-engines in a factory in Fishponds, Bristol during World War I. Sir Roy Fedden, the company's principal designer, developed the 14-cylinder radial Mercury engine during this period. The com ...

based in the Bristol suburb of

Fishponds Fishponds is a large suburb in the north-east of the English city of Bristol, about from the city centre. It has two large Victorian-era parks: Eastville Park and Vassall's Park (once the Vassall Family estate, also known as Oldbury Court). ...

. Fedden wanted to find a suitable airframe to test the Cosmos Mercury radial engine which he was developing, and it was decided to fit the third machine with this engine. It was installed inside a low-drag cowling with exposed cylinder heads, making the aircraft shorter than the Arab-powered machines. The weight went up by . In this form it was known as the Scout F.1 and it was first flown on 6 September 1918. The greater power produced a slightly higher top speed and a much better rate of climb. The third Scout F was the last to fly, although a fourth aircraft was built as a spare airframe. The

brought an end to the Mercury contract, the cancellation of the two outstanding Scout Fs, and the abandonment of hopes of its production.

Specifications (Mercury-powered Bristol Scout F)

References

Notes

Bibliography

* {{Bristol aircraft 1910s British fighter aircraft Scout F Biplanes Aircraft first flown in 1918