On February 4, 1983, a Maule M-5-220C (registration N51599) operated by Thomas L. Jordan was involved in an aviation accident near Near Asotin, WA. Investigators recorded the probable cause as: The #5 piston pin (PN 17658) failed, leading to failure of the aft piston pin boss, which allowed the free end of the connecting rod to damage the #5 cylinder and crankcase near the #5 and #6 crankshaft throws. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An aircraft lost engine power while flying near the Snake River. During an emergency landing attempt on a road, it struck a power line and crashed. Investigation identified a failed piston pin and subsequent engine damage.
Incident Details
While flying in the vicinity of the Snake River, the engine lost power. With limited emergency landing areas available, the pilot elected to land on a road near the river. During a right turn to align with the road, the aircraft collided with a single power line, then crashed.
Investigation Findings
An investigation revealed that the #5 piston pin, part number 17658, had failed. The failure of the aft piston pin boss permitted the free end of the connecting rod to damage the #5 cylinder and the crankcase in the vicinity of the #5 and #6 crankshaft throws. The total flight time of the engine at the time of the incident was 699.5 hours.
Probable cause
The #5 piston pin (PN 17658) failed, leading to failure of the aft piston pin boss, which allowed the free end of the connecting rod to damage the #5 cylinder and crankcase near the #5 and #6 crankshaft throws.