What happened
The pilot reported that the engine quit during flight. With no other options available, he selected the only accessible field for an emergency landing. The terrain was characterized by soft and wet conditions, which likely impacted the effectiveness of braking and directional control. During the ground roll after touchdown, the aircraft nosed over.
The investigation
A subsequent examination of the engine revealed significant mechanical damage. Inspectors found a hole in the engine case located near the number 5 cylinder skirt. Further disassembly of the engine disclosed that the master rod had failed, which is consistent with the catastrophic nature of the event and the resulting structural damage.
Findings
The failure of the master rod was the primary mechanical issue leading to the loss of power. The soft and wet conditions of the landing site contributed to the nosing over incident during the ground roll.