AAIB investigation to Grumman AA-5 Traveller, G-BEZF
Collided with a parked aircraft during taxi, Turweston Aerodrome, 2 September 2018.
Summary:
The pilot planned to fly from Turweston Aerodrome to Coventry Airport and was accompanied by another pilot, who occupied the right seat. Following a walk-round inspection and pushback, he completed the pre-start checklist and started the engine. Upon receipt of taxi clearance, the pilot released the brakes and opened the throttle to commence taxi, but the aircraft veered sharply to the left. He initially applied full pressure to the right brake pedal but when the aircraft did not respond, applied full pressure to both brake pedals. The pilot judged that the aircraft was going to strike a parked aircraft so he closed the throttle, while the accompanying pilot selected the mixture to off. Although the engine had stopped, the propeller was still rotating when G-BEZF struck the parked aircraft. Both occupants were uninjured and exited the aircraft without assistance.
The pilot reported that the collision had resulted from a brake failure, which prevented him from steering or stopping the aircraft. He commented that checking the brake pressure prior to engine start may have identified the fault prior to commencing taxi. Following the accident, another syndicate member tried the brakes with the aircraft stationary and the engine off and noted that the left side brake pedals felt very soft, while those on the right side felt normal. The syndicate member subsequently reported that the aircraft maintainer found no faults when he checked the brakes and assessed that the ‘feel’ of the brake pedals was within normal experience.
Bulletin correction:
A correction was issued concerning this report prior to publication. Full details of the correction can be found below and in the May 2019 Bulletin.
Download amended report: