What happened
The pilot reported experiencing a partial loss of engine power during the takeoff phase. While attempting to activate the fuel boost pump, the pilot became distracted. During this interval, the aircraft drifted to the left and collided with a berm located adjacent to the runway. The pilot noted that the engine subsequently surged and began developing full power only after the collision had occurred.
The investigation
A subsequent examination of the engine revealed that one magneto condenser had malfunctioned. This mechanical failure resulted in an inconsistent spark, which caused the engine to sputter and contributed to the partial loss of power experienced during takeoff.
Findings
The incident was attributed to two primary factors. First, a magneto condenser malfunction led to erratic engine performance. Second, the pilot's attention was diverted while operating the fuel boost pump, which allowed the aircraft to drift off the intended flight path and strike the berm.