Accident
Shortly after takeoff, the private pilot reported that the engine coughed, sputtered, and then quit. An emergency landing was attempted on a farm field. The aircraft sustained substantial damage. The passenger was seriously injured, and the pilot received minor injuries.
Investigation
Post-accident investigation revealed a failure of the right magneto drive gears. A manufacturer's service bulletin specifying replacement of the nylon drive gear with a sintered iron gear at 2,000 hours or at the first overhaul had not been complied with. Engine runup tests conducted after the accident showed that the engine would not run on the right magneto or when both magnetos were selected.
Findings
The investigation determined that the engine failure was caused by a failure of the right magneto drive gears, which resulted from the operator not complying with the manufacturer's service bulletin. The emergency landing resulted in substantial damage to the aircraft and injuries to the occupants.