Incident Overview
During cruise flight, the pilot reported hearing a ticking sound emanating from the engine. Shortly thereafter, the engine ceased operation. In the ensuing emergency landing, the airplane nosed over.
Engine Examination
Post-incident examination of the engine disclosed that teeth from both the crankshaft and camshaft gears were present in the oil sump. A detailed component examination further revealed that the teeth from the camshaft gear had failed due to fatigue. The tachometer indicated that the engine had accumulated 89 hours of operation since its last overhaul in 1981.
Conclusion
The failure of the camshaft gear teeth in fatigue led to the engine failure and subsequent forced landing.