Background
On 16 April 2000, the aircraft, a Piper PA-38-112 registered G-BKAR, had been forced to land in a field southeast of Teesside Airport due to engine power loss. The forced landing was successful. A maintenance engineer examined the aircraft and found contamination in the carburettor fuel bowl, attributed to a microbiological process. The fuel system was cleaned and checked, and a fuel flow check and high power engine runs were completed satisfactorily.
Attempted Recovery
On 18 April 2000, the pilot planned to recover the aircraft by flying it out from an adjacent field back to Teesside Airport. The field was flat with short damp grass. The pilot considered the surface hard, while opinions differed on its firmness. Two instructors paced the field length at approximately 360 metres. A section of hedgerow between this field and an adjacent field had been removed by the farmer, providing an overrun area into the next field with short crop. The takeoff run was planned diagonally across the field toward this gap.
Takeoff and Incident
Before takeoff, basic checks were completed, and the aircraft was taxied to the far end of the field for power checks. Teesside Air Traffic Control provided weather conditions: dry with good visibility, wind 190°/11 kt (headwind component approximately 9 kt), temperature +6°C, dew point +2°C, scattered cloud at 2,500 feet. The pilot selected first stage of flap and applied full power against the brakes. After accelerating an estimated 250 metres, the aircraft became airborne at about 53 kt, then touched down and became airborne again. The pilot then became aware of a reduction in engine power. With insufficient remaining distance to land in the takeoff field, he attempted to land in the overrun field but found the aircraft difficult to control at low airspeed. The left wing dropped and struck a post in the hedge at the left side of the cleared gap, causing the aircraft to crash land in the field. The pilot was not injured.
Post-Accident Examination
The maintenance engineer examined the carburettor again and found no further evidence of contamination. The temperature and dew point values indicated a high probability of carburettor icing at any power.
Takeoff Distance Assessment
The pilot handbook for the aircraft model indicated a ground roll of approximately 177 metres on a dry level paved surface at sea level with an all up weight of 1,670 lbs, a 9 kt headwind, +6°C, first stage flap, and full power before brake release. For a hard level grass surface, a factor of 1.3 increases the ground roll to 230 metres. If the surface is soft, an additional factor of 1.25 increases it to 288 metres. Equivalent distances to clear a 50-foot obstacle are approximately 480 metres and 540 metres. These factors are considered minimum values.