On June 14, 2001, a Commander 114-B (registration N114BW) operated by Gary A. Gallo was involved in an aviation accident near Okmulgee, OK. Investigators recorded the probable cause as: the failure of the #6 cylinder's connecting rod, which resulted in a complete loss of engine power. A contributing factor to the accident was the lack of suitable terrain for the forced landing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot executed a forced landing after a loud bang and total engine power loss. The aircraft struck 4-foot dirt mounds and came to rest upright. Examination revealed a hole in the crankcase and a separated connecting rod.
Accident
The flight had been airborne for three hours when the pilot heard a "loud bang" and the engine lost total power. He executed a forced landing to a field. During the landing, the airplane contacted dirt mounds that were 4 feet high before it came to a stop upright.
Postaccident Examination
Postaccident examination of the airplane revealed that fresh engine oil was adhering to the left side of the fuselage from the engine cowling extending back to the empennage. The oil dipstick was removed and indicated only 2 quarts (8 quart capacity). The oil was black and smelled as though it had been exposed to heat. The engine crankcase displayed a 2.5-inch diameter hole between the #5 and #6 cylinders.
Engine Disassembly
The engine was disassembled and it was noted that the connecting rod for the #6 cylinder had separated from its piston and the crankshaft. The #6 connecting rod journal displayed evidence of thermal damage and metal transfer. Metallurgical examination of the #6 connecting rod end cap and bolt revealed fractures indicative of overstress at extreme temperatures. Additionally, the rod end cap bearing surface displayed fretting and metal transfer. No other anomalies with the engine were noted.