History of the Flight
The pilot, holding a National Private Pilot’s Licence, planned a local area navigation flight followed by visual circuits from Leicester Airport. Runway 28, with a dry asphalt surface, was in use. The wind was from 330° at less than 5 kt, visibility was 25 km, and there was scattered cloud at 4,000 ft aal. The air temperature was 27°C and the dew point was 14°C.
After completing a water test of the fuel in the aircraft’s tanks using the underwing fuel drains, the pilot refuelled the tanks to full. He then completed pre-flight checks, started the engine, and taxied to the holding point for Runway 28, where carburettor heat and magneto checks were completed satisfactorily before takeoff.
Following an uneventful full-power takeoff, at approximately 100 ft aal, the engine started to lose power without any signs of misfiring or rough running. The pilot momentarily retarded the throttle to about 60% power before fully opening it. The engine responded and full power was regained. He continued with a slow climbing turn and planned to land on Runway 10 because the wind was calm. Just after rolling out of the turn, the engine lost all power and stopped.
Unable to reach Runway 10, the pilot elected to land straight ahead in a field of wheat short of and to the right of Runway 10. After touchdown, the aircraft rolled approximately 60 ft, during which the main landing gear collapsed. The uninjured pilot selected the fuel selector, magnetos, and radio to off before vacating the aircraft.
Engineering Inspection
Following the accident, the repair agency inspected and tested the aircraft’s engine and fuel system. This work revealed no pre-existing damage and no mechanical reason for the engine failure. The aircraft’s magnetos were subsequently sent to an independent maintenance organisation for testing. Under test, one magneto stopped when it reached operating temperature due to leaking insulation, and the other showed signs of failure before stopping. At the time of the report, some work remained incomplete, including the results of the full engine test on the airframe, which would be completed once the engine was reinstalled.
Discussion
The test results of the aircraft’s engine, fuel system, and magnetos, along with discussion with the repair agency, suggested that the most probable cause of the engine failure was a double magneto failure. Given the high ambient temperature, it is likely that the magnetos achieved a high operating temperature soon after takeoff and then failed in quick succession. The initial power reduction could be attributed to one of the magnetos showing signs of failure as it achieved a high operating temperature, before they both subsequently failed. Carburettor icing was considered unlikely because the engine was at full throttle during the takeoff run, and the pilot had carried out a satisfactory test of the carburettor heat for 30 seconds prior to takeoff.