On October 7, 1993, a Cessna 180K (registration N61946) operated by Chapman, Wallace J. was involved in an aviation accident near Garfield, WA. Investigators recorded the probable cause as: Fatigue fracture of one of the connecting rod bolts, which led to the breaking of the number three connecting rod. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During cruise at 500 feet AGL, the engine began to vibrate. The pilot shut it down and initiated a forced landing. On ground roll, the airplane collided with rough terrain and ground looped. Investigation found the number three connecting rod broken due to fatigue fracture of a rod bolt.
Accident Overview
While the airplane was in cruise flight at 500 feet above ground level, the engine began to vibrate and shake. In response, the pilot shut down the engine and initiated a forced landing to an open area. During the ground roll, the airplane collided with rough terrain and subsequently ground looped.
Investigation Findings
Post-crash investigation revealed that the number three connecting rod was broken. Metallurgical examination determined that the breaking and damage of the number three connecting rod was the result of fatigue fracture of one of the connecting rod bolts.
Probable cause
Fatigue fracture of one of the connecting rod bolts, which led to the breaking of the number three connecting rod.