One of Britain's top aerobatics pilots who was killed when his plane crashed during a display was suffering from an undiagnosed heart condition, accident investigators have said.
David Jenkins, 61, was flying his Edge 360 plane during a media event to launch the Old Buckenham airshow in Norfolk on April 22 last year when he experienced problems.
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A report by the Air Accidents Investigation Branch (AAIB) found that he crashed after losing control during an "advanced aerobatic tumbling manoeuvre".
The aircraft entered a spin "at relatively low height" and hit the ground "without any apparent attempt at recovery", the investigators stated.
The AAIB said Mr Jenkins was found to have a "serious and previously undiagnosed heart condition" which "may have affected his judgment".
It is possible he became "incapacitated at a critical stage of the flight", the report added.
The moment the aircraft began to lose control was caught on camera by a local television crew.
Witnesses first thought the manoeuvre was part of the daredevil display until smoke began billowing from the ground.
Mr Jenkins was a two-time British advanced aerobatics champion.
He was a member of the Wildcat Aerobatic Team based at Old Buckenham Airfield, near Attleborough, where the event was taking place.
At the time of the crash he was described by friends as "one of the best" and "highly skilled".