What happened
Approximately fifteen minutes into a pleasure flight, the aircraft's engine suffered a partial loss of power. The pilot responded by initiating an emergency descent and landing at a nearby airport. During the landing roll, the aircraft ran off the end of the runway and collided with a bush.
The investigation
A post-accident inspection of the engine revealed that the exhaust valve for the number 4 cylinder had broken. There were no other mechanical failures or malfunctions reported during the examination.
Findings
The primary factor contributing to the incident was the partial loss of power due to the failed component. This mechanical failure necessitated an emergency landing, which resulted in a runway excursion and subsequent collision with vegetation.