Agricultural Aircraft Engine Failure During Return Flight (N23069)

Incident Overview

An agricultural pilot was returning from an aerial application when the engine quit approximately six miles from the destination airport. The pilot attempted to land on a road, but the aircraft struck the edge of a pit, spun across the road, and came to rest facing 180 degrees from the original heading.

Engine Examination Findings

Post-incident examination of the engine disclosed damage to the supercharger impeller consistent with foreign object ingestion. Five of the nine cylinders exhibited low compression and metal particles on the piston and valve surfaces. The left magneto contained brass, copper, and aluminum particles throughout its interior and failed to produce a spark when rotated. The right magneto did produce a spark when rotated; however, three of the nine spark plugs served by this magneto were metal-fouled at the electrodes.