AAIB investigation to Snowbird Mk IV, G-MVOJ
Wing distortion caused loss of control after unintended takeoff, Bedlands Gate, Newby, Cumbria, 22 June 2019.
Summary:
Following a period of maintenance during which the aircraft fabric covering had been replaced, the pilot was carrying out a ground run and taxi test. During taxi the pilot heard a rattle and decided to try to identify its source and so taxied the aircraft at higher speed. To his surprise, the aircraft became airborne but right wing low. Despite his attempts, he could not prevent the aircraft from flying a continuous turn to the right. The aircraft hit a tree and then struck the ground, still right wing low, before ‘pole vaulting’ over a dry‑stone wall. The aircraft came to rest approximately where it had started the taxi. The pilot suffered serious injuries but has since recovered. The tendency for the aircraft to continuously roll right was probably caused by a slight change in the angle of attack of the outer section of the left wing due to a pair of flying wires being overly tight. The lift created by this condition was greater than the left roll control spoiler could counteract.
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