On October 20, 1997, a Piper PA-32RT-300 (registration N2200J) operated by Blue Ridge Air was involved in an aviation accident near Scottsville, VA. Investigators recorded the probable cause as: Fatigue failure of the number 2 connecting rod, with evidence of gauling on connecting rod bolt holes. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot performed a forced landing after experiencing engine vibration and oil leakage. During the ground roll, the airplane struck a 2-foot-high berm. Examination revealed fatigue failure of the number 2 connecting rod.
Event
The pilot leveled off at the cruise altitude of 6,500 feet when the engine began to vibrate and oil was observed leaking from the engine cowling. The vibration and oil flow increased in intensity, prompting the pilot to shut off the engine and execute a forced landing to a field. During the ground roll, the airplane struck a berm approximately 2 feet high.
Examination
Post-accident examination of the engine revealed that the number 2 connecting rod had failed between the wrist pin hole and the crankshaft yoke. A metallurgical examination of the fracture surface identified fatigue as the failure mechanism. Additionally, evidence of gauling was found in the area of the connecting rod bolt holes. Gauling was also observed on the number 6 connecting rod bolt holes.
Background
According to the engine manufacturer, gauling could occur from high loading, such as that produced during overspeed or excessive manifold pressure operation. The operator reported that the airplane was flown by company pilots on charter flights and was also available for rental.
Probable cause
Fatigue failure of the number 2 connecting rod, with evidence of gauling on connecting rod bolt holes.