Piper PA-36-285 N57719 accident near Galena, Kansas

Probable cause

The loss of engine power due to improper maintenance by an unknown individual that led to the degradation and deterioration of the No. 2 piston, which was undetected because of overdue maintenance.

NTSB analysis

Shortly after takeoff, the pilot noticed a decrease in the engine's oil pressure. The engine then sustained a total loss of power, and the airplane collided with terrain during the forced landing. An examination of the engine revealed that the No. 2 piston had failed. In addition, each of the spark plugs had two washers installed, instead of one, and the oil filter contained many metal particles. The two washers likely altered the detonation characteristics of the pistons, causing them to overheat. As the No. 2 piston degraded, metal particles collected in the oil filter. Maintenance records indicate that the engine was overdue for a recommended oil change; the deteriorating piston would likely have been detected during an oil change. The mechanic who performed the last annual inspection was not aware that additional spark plug washers had been installed on the engine.

Text from the NTSB. Open the NTSB docket for CEN13LA280 for the full record.