On July 1, 1988, a Piper J3 (registration N42684) operated by Donald G. Henderson was involved in an aviation accident near Bedford, IN. Investigators recorded the probable cause as: Failure of the magneto timing gear and its four attaching bolts, which resulted in total loss of engine power. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A Cessna 172R experienced total engine failure during cruise flight at 1000 feet AGL after a backfire. The pilot executed a forced landing in rugged terrain, resulting in gear shearing off.
The aircraft was operating in cruise flight at an altitude of 1000 feet above ground level when the pilot heard a backfire from the engine. This was followed by immediate and total loss of power. The pilot attempted to make a forced landing in rugged, rocky terrain. During rollout, the landing gear sheared off.
The investigation revealed failure of magneto timing gear, and its four attaching bolts.
Failure of the magneto timing gear and its four attaching bolts, which resulted in total loss of engine power.