Luscombe 8 N45725 accident near Lincoln, California

Probable cause

The passenger's accidental fall while turning the propeller by hand to start the engine.

NTSB analysis

According to the pilot, the passenger was turning the propeller by hand to start the engine (hand-propping) when the engine “kicked back.” The passenger lost his balance, slipped, and fell to the pavement, striking his head. The pilot stated that after the fall the passenger said that he felt fine and that, en route to their destination, the passenger talked as he normally did. The pilot learned that, two days after the passenger suffered the fall, his wife had him admitted to the local hospital and that, the following day, the passenger had succumbed to what the local medical examiner described as a subdural hematoma as a result of an accidental fall.

Text from the NTSB. Open the NTSB docket for WPR11LA416 for the full record.