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Geoffrey de Havilland
He died on the evening of 27 September 1946 whilst carrying-out high speed tests in the de Havilland DH.108 TG306 which broke-up over the Thames estuary, the remains of the aircraft being discovered the following day in the mud of Egypt Bay, Gravesend, Kent.
Found on the mud flats at Whitstable, his parachute pull ring untouched, the body of Captain de Havilland was found to have suffered a broken neck, the result of the aircraft having undergone severe and violent longitudinal oscillations prior to break-up, which resulted in de Havilland's head striking the cockpit canopy with great force.
A pilot who flew another DH.108, Capt. Eric "Winkle" Brown suggests that a factor in de Havilland's death was due to his height, Brown suffering similar oscillations during a test flight, which due to his shorter stature, did not result in his head contacting the cockpit hood.
The David Lean film The Sound Barrier is based upon this event.
Two of de Havilland's cousins were the actresses Olivia de Havilland and Joan Fontaine.