On November 14, 2007, a Beech A36 (registration N435M) was involved in an aviation accident near EL Centro, CA. Investigators recorded the probable cause as: The failure of maintenance personnel to properly secure the #2 cylinder through bolts. A contributing factor was the lack of suitable terrain for landing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During initial climb through 5,500 feet, the engine experienced a total loss of power. The pilot executed a forced landing in an alfalfa field; the nose gear collapsed and both wings sustained substantial damage. Postaccident examination revealed loose #2 through bolts and deck studs led to bearing failure.
Accident Description
During the initial climb phase at an altitude of 5,500 feet, the engine suddenly and completely lost power. The pilot performed an emergency landing in an alfalfa field. Upon touchdown, the nose landing gear collapsed, and both wings incurred substantial damage.
Examination Findings
A thorough postaccident inspection of the engine identified that the #2 through bolts and deck studs were not properly torqued and had become loose. This condition permitted the #2 bearing half to move out of position, covering the oil transfer tubes located on the bearing support. Consequently, oil flow to the #2 main bearing was restricted, leading to oil starvation. The #2 main bearing failed due to the lack of lubrication, and the #2 connecting rod subsequently separated. The loss of the connecting rod resulted in the total loss of engine power. It was noted that the airplane's #2 cylinder had been replaced 24 hours prior to the engine power loss.