Aircraft and Flight Details
The aircraft involved was a de Havilland DH82A Tiger Moth, registration G-AHVV, manufactured in 1943. It was powered by a single de Havilland Gipsy Major I piston engine. The flight was a training sortie with two crew members on board; no passengers were carried. The pilot held an Airline Transport Pilot Licence and had accumulated 13,000 flying hours, including 8,200 hours on the Tiger Moth type.
Accident Sequence
On 14 September 2008 at approximately 1320 UTC, the aircraft departed from Runway 23 at Dunkeswell Airfield, Devon. Shortly after takeoff, at an altitude of about 200 ft above ground level, the engine speed dropped to idle. The pilot responded by lowering the aircraft's nose to maintain flying speed and initiated a right turn to land in a suitable field. The aircraft cleared a sturdy barbed wire fence during the approach. However, as the aircraft touched down, a cow ran under the aircraft and struck the left wing, resulting in substantial damage. The cow was apparently uninjured. The aircraft rolled to a stop, and both occupants, who were uninjured, vacated the aircraft normally.
Investigation Findings
An examination of the aircraft by a local engineer revealed the presence of corrosion debris within the carburettor float bowl. This debris appeared to have originated from within the float bowl itself. The fuel tank, fuel lines, and fuel filter were found to be clean. It is likely that the corrosion debris blocked the carburettor jets, leading to the reduction in engine power. The engine ran normally once the debris had been removed, supporting this conclusion.