Cessna 172M N391R accident near Canadensis, Pennsylvania

Probable cause

The pilot’s failure to attain a proper glidepath.

NTSB analysis

The pilot performed a preflight inspection of the airplane and an engine run-up with no discrepancies reported before departing. He departed with an adequate supply of fuel and proceeded toward his destination airport. During cruise flight, with the fuel-to-air ratio leaned, the pilot heard an engine sound that he said was similar to a cylinder not firing; the engine then experienced significant vibration and a partial loss of power. Attempts to restore engine power were unsuccessful. The flight was vectored by an air traffic controller to the Cherry Ridge Airport (N30), and on the first approach to the 2,405-foot-long grass downsloping runway designated 20, the flight was high and fast resulting in a bounced landing necessitating a go-around. He executed a 180 degree turn to land on runway 2, and while on final approach, the airplane was allowed to descend below the elevation of the runway resulting in undershoot followed by a nose-over. While the postaccident inspection of the engine revealed a discrepancy with one magneto and very low compression from the No. 4 cylinder, the pilot stated that his in-flight check of each magneto revealed satisfactory results.

Text from the NTSB. Open the NTSB docket for ERA12LA539 for the full record.