Incident Overview
During routine maintenance, an engine was run up to full power while the airplane's tow bar remained attached. As the nose strut compressed under the load, the propeller struck the tow bar. A subsequent service bulletin addresses this issue, stating that the engine should be disassembled and inspected for damage after such an event.
Maintenance Facility Actions
The maintenance facility did not inform the owner of the full extent of the damage caused by the propeller strike. As a result of the strike, the crankshaft main bearings rotated in their saddles and failed mechanically. This rotation led to the blockage of oil passages within the engine.
Engine Failure and Forced Landing
The blockage of oil passages caused the subsequent failure of the number two cylinder connecting rod cap bolts, culminating in a total engine failure. The pilot was forced to land, but suitable terrain for a forced landing was not available. The aircraft impacted in soft cultivated terrain.
Conclusion
The incident highlights the mechanical consequences of a propeller strike during ground operations and the importance of proper communication regarding damage assessment.