The accident was notified to the Air Accidents Investigation Branch (AAIB) at 1417 hrs on 21 August 2004 and the investigation began the same day. The AAIB Investigation team consisted of:
Mr D Miller (Investigator-in-Charge)
Mr N Dann (Operations)
Mr B McDermid (Engineering)
Mr P Wivell (Flight Recorders)
The Pegasus Quik microlight, with an instructor and passenger on board, departed Rochester Airfield for a trial lesson. Thirty five minutes into the flight, as it was flying at 500 ft along the north coast of the Isle of Sheppey, it pitched up steeply to the near vertical and entered a series of tumbling manoeuvres. As the microlight tumbled the trike unit, containing the two occupants, separated from the wing and descended vertically to the ground. Neither the pilot nor his passenger survived the impact. The initiation of the pitching moment and subsequent entry into the tumbling sequence was brought about by the failure of the right upright upper fitting, which caused full nose-up trim to be suddenly applied.
Some time previously the microlight’s uprights upper fittings had been modified to comply with Service Bulletin 116 requiring the fitting of additional rivets. The additional rivets were not only fitted incorrectly, and without reference to the Service Bulletin, but two of them did not match the specification of those rivets supplied by the manufacturer in the modification kit. Additionally, no duplicate independent inspection was carried out on the correct embodiment of the modification.
The investigation identified the following causal factors:
(i). Failure of the right upright upper fitting caused the microlight to enter a tumble manoeuvre from which it was not possible to recover.
(ii). Service Bulletin 116, which introduced additional rivets in the upper fitting, was not correctly embodied.
Eleven safety recommendations have been made as a result of the investigation.
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G-STYX 2-2005.pdf (953.12 kb)