Beech V35 N5655D accident near Trussville, Alabama

Probable cause

The failure of the No. 2 connecting rod due to oil starvation, which resulted in a total loss of engine power.

NTSB analysis

The pilot reported that, during approach, he heard a "loud pop" and that the engine then lost total power. The airplane was too far away to glide to the destination airport, so the pilot chose to perform a forced landing to a field, which resulted in substantial damage to the fuselage.

Subsequent teardown examination of the engine revealed evidence of oil starvation at the No. 2 connecting rod, which resulted in its separation from the crankshaft and its subsequent puncturing of a hole in the crankcase. The oil tube from the main bearing to the No. 2 connecting rod was found clear and unrestricted. At some point during the life of the engine, the interior of the rocker covers had been coated with an unapproved material. The coating material had been flaking off during operation and had been cleaned from two of six of the rocker covers. The four remaining covers still contained the coating material, but it could not be determined if the material caused the oil restriction because none of the material was found in any of the oil or oil passages. However, it is possible that any restricting material dislodged and escaped during the engine failure.

Text from the NTSB. Open the NTSB docket for ERA14LA052 for the full record.