Dunsfold declared inactive in 1946 but was used again in 1948 and 1949 as part of the Berlin Airlift. In 1950 The Hawker Aircraft Company acquired the lease of the site. In October 1960 the then Hawker Siddeley flight tested its Hawker P.1127 prototype, the development aircraft that led to the Hawker Siddeley Harrier, the first VTOL jet fighter bomber. Final assembly of the Harrier and the Hawk trainer aircraft was at Dunsfold. Hawker Siddeley became part of British Aerospace in 1977. On 2 July 1986 British Aerospace's deputy chief test pilot Jim Hawkins was killed at Dunsfold when his developmental
Hawker Siddeley Harrier the P.1154 was cancelled, as the Royal Navy had already begun procurement of the McDonnell Douglas Phantom II and the RAF placed a greater importance on the BAC TSR-2's ongoing development. Work continued on elements of the project, such as a supersonic PCB-equipped Pegasus engine, with the intention of developing a future Harrier variant for the decades following cancellation. Following the collapse of the P.1154's development the RAF began considering a simple upgrade of the existing subsonic Kestrel and issued Requirement ASR 384 for a V/STOL ground attack jet. Hawker Siddeley received an order for six pre-production aircraft in 1965,