The 1952 Farnborough Airshow DH.110 crash was an air show accident involving a de Havilland DH.110 which killed 29 spectators as well as pilot John Derry and onboard flight test observer Anthony Richards. The DH.110, a prototype, was being demonstrated at the Farnborough Airshow when during a manoeuvre, the aircraft broke up. The cause was a faulty wing leading edge design. The DH.110 was grounded and strict safety procedures were subsequently enacted. After modifications to the design the DH.110 entered service with the Royal Navy as the de Havilland Sea Vixen.
The event was the last British air show in which spectators were killed until the 2015 Shoreham Airshow crash in which 11 people died, three of whom were reported to have been observing the event from the A27 rather than the designated spectators' area within the airfield. In addition, five people were killed while on a helicopter experience at the Biggin Hill Air Show in 1977.
The planned demonstration of the DH.110 on that day was nearly cancelled when the aircraft at Farnborough, an all-black night fighter prototype, became unserviceable. It was De Havilland's second DH.110 prototype, and had been taken supersonic over the show on the opening day. Derry and Richards left Farnborough to collect WG 236, the first prototype, and flew it from Hatfield to Farnborough with just enough time to start their slot.
Following a low-level supersonic flypast and during a left bank at about 450 knots (830 km/h) toward the air show's 120,000 spectators, the pilot started a climb. The outer starboard wing and, immediately afterward, the outer port wing broke off the aircraft, followed by both engines and the cockpit—the latter injuring several spectators. One engine broke into two sections and "ploughed into ... Observation Hill", injuring and killing numerous other spectators.
One eyewitness was Richard Gardner, then five years old. He recalled in adulthood:
I'll never forget, it looked like confetti, looked like silver confetti. The remaining airframe floated down right in front of us. It just came down like a leaf. And then the two engines, like two missiles, shot out of the airframe and hurtled in the direction of the airshow. There was a sort of silence, then people, one or two people screamed but mostly it was just a sort of shock. You could hear some people sort of whimpering which was quite shocking.
Sixty-three years later, speaking on the BBC Today program in the wake of the Shoreham air disaster, author Moyra Bremner recalled her own traumatic experience. A huge bang silenced the crowd and was followed by "My God, look out" from the commentator. Bremner, standing on the roof of her parents' car, realized that an engine was heading straight towards her. It passed a few feet over her head, a "massive shining cylinder", and then plunged into the crowd on the hill behind.
Following the accident the air display programme continued once the debris was cleared from the runway, with Neville Duke exhibiting the prototype Hawker Hunter and taking it supersonic over the show later that day.
Both The Queen and Duncan Sandys, the Minister of Supply, sent messages of condolence, and jets at air shows were obliged to keep at least 230 m (750 ft) from crowds if flying straight and 450 m (1,480 ft) when performing manoeuvres and always at an altitude of at least 150 m (490 ft). The coroner's jury recorded the deaths of Derry and Richards as "died accidentally in the normal course of their duty."
The jury recorded that "the deaths [of the spectators] were accidental", adding that "no blame is attached to Mr. John Derry". The accident report of 8 April 1953 stated the manoeuvring had caused an airframe instability because of a faulty D-nose leading edge arrangement (which had successfully been used in the lighter subsonic de Havilland Vampire). The redesigned DH.110 resumed flights in June 1953 and was eventually developed into the de Havilland Sea Vixen naval fighter.