Origins In 1946, the
de Havilland Aircraft Company conducted discussions with the
British Admiralty on its requirements for a future
jet-powered all-weather,
radar-equipped
fighter. The design of the DH.110 used the
twin-boom-tail design layout of the
de Havilland Vampire and
de Havilland Venom. It had an all-metal structure, 45-degree swept wings, and an armament of four 30 mm
ADEN cannons. By early 1949 the DH.110 design was expected to fulfil four requirements: F4/48, F5/49 (a long range RAF fighter), N.40/46 (naval night fighter) and N.8/49 (naval strike aircraft). Three prototypes were needed for F.4/48, four for common RAF and RN development, and two each for the other three roles and by July the authorities were ready to order the 13 prototypes In 1949 the Royal Navy decided to procure the
de Havilland Sea Venom which, as a development of an existing aircraft, was cheaper, and would be available sooner to meet its immediate needs for a jet-powered night fighter to replace its fleet of piston-engined
de Havilland Sea Hornets and
Vought F4U Corsairs. The RAF decided to cut its order to two prototypes. On 26 September 1951, an initial prototype was completed and conducted its
maiden flight from the
Hatfield Aerodrome, flown by the test pilot
John Cunningham. Early flight tests of the prototype demonstrated that the aircraft's performance exceeded expectations. By the following year, the prototype was regularly flying in excess of the
speed of sound. Following a demonstration of its ability to break the sound barrier during a low level flight
the aircraft disintegrated and debris landed in the midst of spectators, killing 31 people including the crew of two, the test pilot
John Derry and his flight-test observer, Tony Richards. Subsequent investigation of the accident traced the failure to faulty design of the wing leading edge section ahead of the
main spar. The design had been satisfactory for the earlier Vampire and Venom but not for the higher stresses induced by the rolling pull-out manoeuvre at flown by the DH.110 prototype at Farnborough. The leading edge skin, without the extra reinforcing structure that would be added later, buckled, which resulted in the outer portions of the swept-back wings being torn off (similar display routines had been flown on preceding days by the other prototype DH.110 which had an
aerodynamic fence providing external stiffening for the skin over the area where the buckling originated.). The subsequent shift in the DH.110's
centre of pressure caused the aircraft to pitch up, the cockpit and tail sections breaking away and the engines being torn from the airframe by the
g loading. One of the engines hit an area crowded with spectators at the end of the runway, causing the majority of the deaths. Sixty other spectators were injured by debris from the cockpit landing close to the main spectator enclosures along the runway. This incident led to new safety regulations for
air shows in the UK, and no member of the public died as a result of a British airshow flight for more than 62 years, until the crash of a
Hawker Hunter warbird killed 11 people during the
Shoreham Air Show on 22 August 2015. As a result of these changes the DH.110 was no longer able to exceed the speed of sound, only reaching Mach 0.95 in a steep dive where its controls were immovable until passing . By this time, the Royal Air Force announced the abandonment of its interest in the DH.110, after deciding to buy the Gloster Javelin instead. The Fleet Air Arm had decided that it would adopt the aircraft as a replacement for its interim fleet of Sea Venoms. In February 1955, an order was placed for 110 naval aircraft, which received the name
Sea Vixen. In June 1955, a semi-navalised prototype,
XF828, was completed for conducting carrier flight deck suitability trials. On 20 June 1955, this aircraft made its first flight from de Havilland's facility at
Christchurch Airfield in
Dorset. The following year, XF828 performed its first arrested deck landing on the Royal Navy's aircraft carrier . In April 1956, the finalised production drawings were formally issued. On 2 July 1959, the first Sea Vixen-equipped squadron was formed. Production Sea Vixens were manufactured at first by de Havilland at its former
Second World War Airspeed Ltd. "
shadow factory" at
Christchurch near
Bournemouth, starting in March 1957. The changes in aerodynamics meant that the 1,000 lb bomb could no longer be carried. Visually the FAW.1 and FAW.2 could be distinguished by the tail booms which extended forward over the wing leading edges of the FAW.2. In 1962, the Sea Vixen FAW.2 conducted its maiden flight; the type entered service with frontline squadrons in 1964. A total of 29 FAW.2s were newly built along with a further 67 FAW.1s that were rebuilt to FAW.2 standard. In 1966, the original FAW.1 begun to be phased out and in 1972, the career of the Sea Vixen FAW.2 came to an end. missiles. The Sea Vixen FAW2 could be armed with up to four Red Top infrared-homing missiles. The Red Top could home on to heat sources generated by kinetic heating of a fast-approaching supersonic target such as the
Tupolev Tu-22 bomber. The Red Top system was integrated into the AI 18R (R for Red Top) radar. From 1969 the Sea Vixen FAW2 practised intercepts of a supersonic target against the
Concorde SST in flight tests over the Irish Sea. The Admiralty had planned to replace the Sea Vixen with the
McDonnell Douglas Phantom FG.1. The aircraft carriers HMS
Ark Royal and were both planned to be refitted to properly carry and fly the new fighters. Due to defence cuts, and following the decommissioning of HMS
Eagle, only HMS
Ark Royal underwent the conversion to fly the new Phantom FG.1. A small number of Sea Vixens subsequently saw service as
drones, as the
Sea Vixen D.3. Only four aircraft were converted to the D.3 standard, though three more were dispatched to Farnborough to undergo conversion, but ultimately went unconverted. The last remaining airworthy Sea Vixen (XP924) was a D3 conversion. A number of other Sea Vixens became target tugs as the
Sea Vixen TT.2. ==Design==