Piper PA-28-160 N9770J accident near Eau Claire, Wisconsin

Probable cause

The engine fire that began for undetermined reasons following numerous engine start attempts.

NTSB analysis

The pilot attempted to start the engine six times before the battery died. He recharged the battery and attempted six more engine starts before ceasing further attempts. He said that during each engine start attempt, he applied the engine primer three times and pumped the throttle control two times. The throttle control was positioned about ¼ inch forward during each start attempt. At times during the start attempts, he placed the mixture control into idle cutoff and ran the engine starter.

The pilot and one passenger exited the airplane while one passenger remained inside. The passenger who exited the airplane noticed a small flame inside the engine cowling. The pilot told the passenger inside the airplane to move the mixture control to idle cutoff. The passenger then exited the airplane. The fuel selector was not turned to the off position. A large fire the erupted from the engine compartment, which destroyed the airplane. Fire damage precluded determination of the fuel and ignition sources of the fire.

Text from the NTSB. Open the NTSB docket for CEN23LA099 for the full record.