What happened
On 6 May 2008, an Avid Speedwing, registration G-BTMS, was performing a private flight from a 300-metre grass strip located at Burtenshaw Farm, East Sussex. The pilot had conducted a lengthy engine ground run on the preceding day following the replacement of the engine spark plugs.
During the takeoff roll, the pilot noticed a change in engine noise and a gradual decrease in RPM at approximately 150 ft agl. In response to the loss of engine power, the pilot turned the aircraft back toward the departure runway to perform a downwind landing.
Upon approaching the threshold, the pilot was aware of a high groundspeed due to a strong tailwind. Although the wheel brakes were applied after touchdown, the aircraft struck a bump mid-way down the runway. This impact caused the aircraft to become airborne again for approximately 30 metres. Ultimately, the pilot was unable to bring the aircraft to a halt, resulting in a collision with a parked car. There were no injuries to the pilot, and damage to both the aircraft and the car was minor.
The investigation
The investigation focused on the mechanical state of the Rotax 582 piston engine and the circumstances of the landing. Investigators reviewed the pilot's recent maintenance activities, noting the recent installation of new spark plugs. An engineer subsequently examined the engine to identify any mechanical failures or defects that could have caused the power reduction.