Accident Details
On 23 November 1997 at 1145 UTC, a Piper PA-28-161 (registration G-BJBY) sustained damage during a takeoff accident at Old Sarum Airfield, Wiltshire. The aircraft, manufactured in 1981, was powered by a Lycoming O-320-D3G piston engine. The private flight, planned for about one hour in the local area, had one pilot and two passengers on board. The pilot, aged 54, held a Private Pilot's Licence with 1,126 hours total flying experience, including one hour on type. His recent flying totaled 6 hours in the last 90 days and 1 hour in the last 28 days.
Flight History
Before the flight, the pilot calculated takeoff performance using 25° of flap for the soft grass runway. The calculations, which included appropriate factors for wet grass, indicated sufficient takeoff distance. The aircraft was refuelled with 20 US gallons, and two passengers were boarded. After satisfactory power checks, the pilot lined up on Runway 06 and selected 25° of flap. He observed a similar aircraft carrying four people successfully take off from the same runway ahead of him.
During the takeoff run, the pilot noted slow acceleration, which he attributed to the ground conditions. However, acceleration through 50 kt was described as 'sluggish'. He rotated the aircraft at 52 kt, expecting to clear a fence and mound at the end of the runway. The aircraft took a long time to become airborne, and the rate of climb appeared minimal. The pilot considered there was insufficient distance to stop safely and continued the takeoff, hoping to clear the obstacles. The aircraft clipped the fence and the top of the mound before coming to rest abruptly on waste ground beyond. The pilot switched off the electrical system and fuel, checked on his passengers, and helpers quickly arrived to assist with evacuation. Both the pilot and passengers sustained minor injuries.
Examination Findings
Subsequent examination of the aircraft revealed that the flaps had been set to 40° instead of the intended 25°. Evidence of the 40° setting was found in distortion of the detent in the flap quadrant. The 40° flap setting would have accounted for the aircraft's poor acceleration and inability to climb sufficiently. The aircraft sustained crushing to the engine bay, destruction of the landing gear, and damage to both wings and the tail area.