The de Havilland Vampire is a British jet fighter which was developed and manufactured by the de Havilland Aircraft Company. It was the second jet fighter to be operated by the RAF, after the Gloster Meteor, and the first to be powered by a single jet engine.
Development of the Vampire as an experimental aircraft began in 1941 during the Second World War, to exploit the revolutionary innovation of jet propulsion. From the company's design studies, it was decided to use a single-engine, twin-boom aircraft, powered by the Halford H.1 turbojet (later produced as the Goblin). Aside from its propulsion system and twin-boom configuration, it was a relatively conventional aircraft. In May 1944, it was decided to produce the aircraft as an interceptor for the Royal Air Force (RAF). In 1946, the Vampire entered operational service with the RAF, only months after the war had ended.
The Vampire quickly proved to be effective and was adopted as a replacement of wartime piston-engined fighter aircraft. During its early service it accomplished several aviation firsts and achieved various records, such as being the first jet aircraft to cross the Atlantic Ocean. The Vampire remained in front-line RAF service until 1953 when its transfer began to secondary roles such as ground attack and pilot training, for which specialist variants were produced. The RAF retired the Vampire in 1966 when its final role of advanced trainer was filled by the Folland Gnat. The Royal Navy had also adapted the type as the Sea Vampire, a navalised variant suitable for operations from aircraft carriers. It was the service's first jet fighter.
The Vampire was exported to many nations and was operated worldwide in numerous theatres and climates. Several countries used the type in combat including the Suez Crisis, the Malayan Emergency and the Rhodesian Bush War. By the end of production, almost 3,300 Vampires had been manufactured, a quarter of these having been manufactured under licence abroad. de Havilland pursued the further development of the type; major derivatives produced include the DH.115, a specialised dual-seat trainer and the more advanced DH.112 Venom, a refined variant for ground attack and night-fighter operations.
Development
Origins
In January 1941, Sir Henry Tizard made an informal approach to the de Havilland Aircraft Company, suggesting that the company proceed to design a fighter aircraft that would use the revolutionary new jet propulsion technology then under development, along with an appropriate engine to go with it. Although no official specification had been issued, de Havilland proceeded to design a single-engined aircraft that had air-intakes set into the wing roots to feed a centrally mounted engine, which used a centrifugal compressor.
The aero-engine designer Major Frank Halford had been given access to Frank Whittle's pioneering work on gas turbines, which, for the projected jet-powered fighter, Halford decided to proceed with the design of a "straight through" centrifugal engine capable of generating 3,000 lb of thrust, which was considered to be high at the time. Halford's engine emerged as the Halford H.1. By April 1941, design work on the engine had been completed and a prototype H.1 engine performed its first test run one year later.
The low power output of the early jet engines had meant that only twin-engined aircraft designs were considered to be practical; as more powerful jet engines were quickly developed, particularly Halford's H.1 (later known as the de Havilland Goblin), the practicalities of single-engined jet fighter were soon realised. de Havilland was approached to produce an airframe for the H.1 as insurance against Germany using jet bombers against Britain; this was considered more important than de Havilland's suggestion of a high-speed jet bomber. Its first design, the DH.99, was set out in a brochure dated 6 June 1941; it was an all-metal, twin-boom, tricycle undercarriage aircraft armed with four cannon. The use of a twin boom enabled the jet pipe to be kept relatively short, which avoided the power loss that would have occurred if a long pipe was used, as would have been necessary in a conventional fuselage. It also put the tailplane clear of interference from the exhaust. Performance was estimated at at sea level and initial climb of on 2,700 lb thrust. The Ministry of Aircraft Production (MAP) representative expressed doubts regarding the lack of detail, estimations for the aircraft's performance and optimistic structure weight; the project received permission to proceed in July 1941.