Bristol Beaufort

During 1935 Specifications M.15/35 and G.24/35 were drawn up by the Air Ministry. Specification M.15/35 called for a torpedo bomber and G.24/35 for a general reconnaissance/bomber aircraft to replace the Avro Anson. For the latter specification the Canadian built Bristol Bolingbroke was earmarked, so Bristol began work on the torpedo bomber. Known as the Type 150 the idea for this aircraft was sent to the Air Ministry in November 1935. This would see a modified Bristol Blenheim design so the fuselage would be able to take more powerful engines and a torpedo.

With the Type 150 idea now submitted the design team at Bristol decided that it was able to design an aircraft that could meet not only Specification M.15/35 but also Specification G.24/35. Known as the Type 152 this would also use the Blenheim as the base and would have a lengthened fuselage which would hold a crew of three, which would consist of pilot, navigator and gunner/camera/wireless operator. The longer fuselage would also allow for the torpedo to be fitted, although not fully enclosed, in the fuselage. The Air Ministry showed an interest in the new design, however, they wanted the aircraft to hold a crew of four, requiring Bristol to redesign the aircraft, with Specification 10/36 issued for production of the Beaufort.

It became clear early on that due to the Beaufort being almost 25% heavier than the Blenheim that the intended Bristol Perseus engines would have to be replaced, otherwise the performance of the aircraft would suffer. The decision was taken to use a new engine designed by the company, the Taurus, this was a bit of a gamble as the Taurus hadn't been cleared for production yet. However, a number of problems had to be overcome before the prototype could make its maiden flight. One of the hurdles Bristol had to overcome occurred due to the Taurus engines overheating. Finally, on the 15th October 1938, 26 months after the order was placed, the prototype Bristol Beaufort flew for the first time.

With the prototype undergoing the usual tests for new aircraft, a number of changes would be made as a result. These included the addition of another machine-gun to the dorsal turret and doors added to the main landing gear so that when retracted it was enclosed. This meant it would be a further 13 months before the Beaufort entered service. This would be with No. 22 Squadron in November 1939, replacing their Vickers Vildebeest. The Beaufort's operational service with the Royal Air Force began on the 15th April 1940 when No. 22 Squadron used the type for minelaying. Further engine problems though, would see all operational aircraft grounded in May 1940. Modifications to the engines solved the problems and with these issues now sorted the Beaufort would enter service in larger numbers, although this would take time. In fact by the following summer No. 22 and No. 42 Squadrons were still the only two equipped with the type with a further seven equipped later on. Bringing the total to nine squadrons, six home squadrons and three in the Middle East.

Shortly after the first prototype flight the Australian government were looking to the Beaufort for its own needs and after a British Air Mission visited the country in 1939 it was decided production of the type could be done in Australia. With the go ahead now given, Melbourne and Sydney would be the locations for the two assembly plants with production backing from a number of railway workshops. A number of airframe parts as well as the eighth production Beaufort would be sent to Australia.

Whilst British built Beaufort Mk Is were powered by Bristol Taurus engines, Australia had decided to use the 1,200-hp Twin Wasp which they would build under licence from Pratt & Whitney. This would result in the fin area being increased to help improve stability. The Department of Aircraft Production or DAP Beaufort, as Australian built examples would be known as, were to be made for the RAF for use in the Far East and 180 were ordered. Production of the type would begin in May 1940 and these aircraft would be designated Beaufort Mk V. The following May would see the first Australian assembled Beaufort make its maiden flight before being followed three months later by the first Australian built example. With the entry of Japan into the Second World War (1939 - 1945) in December 1941 it was decided that the Royal Australian Air Force would take delivery of the Beaufort Mk Vs instead and these began to enter service in the summer of 1942.

The difference between the Beauforts that followed was mainly the engine and propeller used. The Mk VI was fitted with Curtiss propellers and the Mk VII with Hamilton propellers. Both aircraft were powered by imported S1C3-G Twin Wasp engines due to a lack of license built examples. The Mk VIII which followed was to be the most produced Australian example with 520 being built and these would revert back to being powered by license built engines, in this case the S3C4-G Twin Wasp. Other changes included Loran navigation and an increased fuel capacity. The final Australian variant would be the Mk IX. These were a number of different variants which had their dorsal turret and other armament removed and would be used as transport aircraft. In total 700 of the type were built in Australia by the time production ended in August 1944. These would remain in service until the end of the Second World War serving in the Pacific theatre of war.

With the use of the Pratt & Whitney Twin Wasp engine by the Royal Australian Air Force on their Beauforts the Air Ministry requested that the engine be used for the next British built Beaufort. This was to be the Mk II, and in November 1940 the prototype aircraft flew for the first time. Followed the following September when the first production Mk II flew. In the end only 164 would be manufactured as the UK suffered a shortage of the Twin Wasp engine. Production therefore switched back to the Beaufort Mk I which featured a number of changes, including a strengthened structure and upgraded Bristol Taurus XII engines. The Mk II would be put back into production again, although this time as a trainer, under the designation T.Mk II.

It was intended for the Beaufort Mk III to be powered by a pair of Rolls-Royce Merlin XX engines, however this would never reach the prototype stage, and the final variant, the Mk IV, saw a sole prototype example built with power supplied by the 1,250-hp Taurus XX engine.

The Bristol Beaufort would spend three years (1940 - 1943) as Coastal Command's standard torpedo bomber and was in constant service, taking part in the early battles against the German surface fleet. This included raids againts the battle cruisers Gneisenau and Scharnhorst and the heavy cruiser Prinz Eugen.

By the time production ended on the 25th November 1944 a total of 2,130 Beauforts had been built.