What happened
On 4 August 2000, a Piper PA-32-300, registration G-MCAR, was involved in an incident at RAF Henlow, Bedfordshire, during a private flight preparation. The pilot had intended to fly to the Channel Islands and had taxied the aircraft to the refuelling area. To facilitate the movement of another aircraft, a Cessna, the pilot had pushed the G-MCAR approximately 40 feet away from the refuelling point.
Once the area was clear, the pilot attempted to start the engine. Following an initial failure, a hot start procedure was initiated. Upon the second attempt, the engine ignited, but the aircraft immediately accelerated forward at a high power setting. The pilot applied the toe brakes, but the aircraft continued to move, leaving skid marks on the damp ground for the final 15 feet of its path. The aircraft eventually struck a concrete bund surrounding the refuelling area, which caused the starboard undercarriage to be torn off and the wing spar to sustain damage. The impact also broke a fuel drain, leading to a fuel spillage that floated on rainwater within the bund, creating a fire risk until airfield fire services arrived to apply foam.
The investigation
Investigators examined the aircraft and the circumstances surrounding the engine start. The investigation established that the engine had been shock loaded and the propeller sustained damage during the event. Evidence from the site, including photographs of skid marks on the damp earth, indicated that the aircraft's uncontrolled movement began shortly after the engine ignited. The pilot confirmed that the parking brake had not been re-engaged after the aircraft was pushed back to clear the way for the other aircraft.