The Beaufighter had dual Bristol Hercules Engines[N 1] capable of propelling the aircraft at speeds of up to 514 km/h. The Beaufighter also had a crew of two men and armament that consisted of four Hispano 20mm autocannons, six 7.7mm machine guns,[N 2] combined with one 964 kg torpedo or two 113 kg bombs or eight 90 lb rockets.
The Beaufighter began in Autumn, 1938, as a private venture by Leslie Frise, Chief Designer of Bristol Aircraft, who was aware of the delays to the Westland Whirlwind, intended to fulfill a requirement for a long range fighter equipped with four 20mm autocannons. As it would have taken too long to develop an all new type, Frise submitted a proposal for a heavy fighter based on the Beaufort torpedo bomber,[N 3] to take advantage of the Beaufort's strong wings which, when mated to more powerful engines, would be eminently suitable.
Early estimates for the type quoted a speed of 370 mph, based on the use of Bristol Hercules engines. The main objective was to combine as many Beaufort components as possible, such as wings, tail unit, centre fuselage and undercarriage, with a new, smaller, forward fuselage.
In order to avoid the delays from a competitive tender and a separate prototype stage, Bristol intended to convert a partially completed Beaufort into a prototype for the new aircraft,[N 4] while manufacturing production aircraft ordered off the drawing board. Following the firm's promise that an immediate order would result in production starting in early 1940, an order for 300 examples was agreed on 24 February 1939 by the Air Council Committee on Supply, who appreciated Bristol's experience in producing interim fighters by converting Blenheim bombers, the use of common Beaufort parts, and Bristol's capability in fulfilling the production programme.
After the mock up was examined on April 17, 1939, draft specification F.17/39 was finally approved in July, describing the Beaufighter as an interim type to precede the Whirlwind. Speed at 15,000 ft was to be not less than 350 mph, with speed at 5,000 ft expected to be 330 mph, thanks to the two speed superchargers. Full load service ceiling was expected to be 30,000 ft, with time to reach 20,000 ft expected to be about 10 mins. The aircraft would carry two crew, and a fixed armament of four 20mm cannon. The Wright Cyclone and Rolls Royce Griffon were briefly considered as alternative engines, with R3177 eventually testing a pair of Griffon IIBs with four bladed propellers.
A pair of converted Beaufort were ordered, although these were considered non standard, together with a pair of new build airframes. The first pair were fitted with De Havilland constant speed propellers in April 1939, because their first batch Hercules engines had no provision to accommodate fully feathering units. Although construction of the converted Beauforts was started immediately, with the expectation that the Beaufort fuselage could easily be converted, the smooth progress was soon interrupted, as the layout of the cannon fighter was so different that the entire fuselage had to be redesigned
On 3 July 1939, a production contract for 300 examples was placed to Specification F.17/39, with the first prototype, R2052, making it's initial flight with Captain Uwins at the controls, exactly two weeks later. Powered by a pair of two speed supercharged Hercules engines, R2052 was delivered to the RAF for official trials on 2 April 1940. Flying at an all up weight of 16,000 lb, R2052 soon reached 335 mph at 16,800 ft. By the end of April, second prototype R2053 had also been delivered. This aircraft was fitted with full equipment, resulting in all up weight increasing to 18,531 lb.
- Australia: Received a number of aircraft of various marks built in Britain, with serial prefix A19, and 364 Mk 21s built in Australia, with serial prefix A8. The first flight by a Mk 21 took place on 26 May 1944, with the final new build example being delivered in October 1945. These remained in RAAF service until 1960.
- Canada: At least one unit of the Royal Canadian Air Force operated the Beaufighter TF Mk X as part of the RAF.
- United States of America: The USAAF received sufficient examples of the Mk VIF fighter, taken from RAF stocks, to equip four squadrons of the 12th Air Force in the Mediterranean during 1942-43. These units - the 414th, 415th, 416th and 417th - retained the Beaufighter until the arrival of the P-61 Black Widow in the Med, shortly before VE-Day.
- The exceptions was the Mk II, which used a pair of Rolls Royce Merlins, the two Mk V test aircraft converted from Mk II airframes, and one off examples fitted with Rolls Royce Griffons or Wright GR-2600 Cyclones. The nacelle for the Merlin installation were later used to convert the twin engined Avro Manchester into the four engined Avro Lancaster.
- The machine guns were not fitted to the first 50 examples.
- This suggested two armament schemes. The main scheme featured a turret containing a pair of 20mm Hispano autocannon. The alternative scheme, which was eventually selected by Assistant Chief of the Air Staff Shalto Douglas, featured four fixed Hispanos.
- Known during early development as the Bristol Cannon Fighter
- Aeroplane Monthly June 2005 edition Page 54
- Gunston, Bill. Illustrated Directory of Fighting Aircraft of World War II. Salamander Books. 1988. ISBN 0-86101-390-5 Page 26
- Green, William and Gordon Swanborough. Complete Book of Fighters. Salamander Books. 2001. ISBN 1-84065-269-1 Page 100
- Aeroplane Magazine Database section August 2003. Page 61
- Aeroplane Magazine - August 2003. Page 62
- Green, William. Famous Fighters of the Second World War. Purnell Book Services. 1975. Page 51
- World Aircraft Information Files Aviation Partwork. Midsummer Books Ltd. File 51 Sheet 5: Bristol Beaufighter - Briefing
- Gunston, Bill - Fighting Aircraft. Page 29
- World Aircraft Information File 51 Sheet 2: Bristol Beaufighter - 'Coastal' variants Cite error: Invalid
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