What happened
While the aircraft was engaged in a cruise climb phase of flight, the engine began to emit unusual metallic noises accompanied by a noticeable loss of power. Recognizing the mechanical failure, the pilot initiated an emergency procedure. Despite the off-airport nature of the landing site, the pilot successfully executed a controlled emergency landing without further incident.
The investigation
Following the event, the engine was removed and disassembled for detailed examination. Technical inspectors discovered that the connecting rod bearing on the number two cylinder had shifted within its journal race. This displacement resulted in a severe oil starvation event, leading to thermal distress of the internal components. The root cause of why the bearing shifted could not be determined through the available evidence.
Findings
The primary factor contributing to the incident was the mechanical failure of the number two cylinder connecting rod bearing. This failure led directly to oil starvation and subsequent thermal damage within the engine assembly. While the specific reason for the bearing shift remains unknown, the resulting loss of lubrication was sufficient to cause catastrophic engine failure during flight.
Safety message
Regular inspection of engine components, particularly bearings and lubrication systems, is critical for detecting early signs of wear or displacement before they lead to in-flight failures. Pilots should remain vigilant for unusual engine noises or performance changes during climb phases.