Probable cause: An in-flight collision with a bird.
Pilot hits ditch after refueling
Probable cause: The pilot’s failure to use taxiways shown on the airport diagrams and his subsequent failure to avoid a ditch.
Universal joint fails in flight
Probable cause: The failure of the universal joint in the pilot-side flight control yoke due to the fatigue fracture of a rivet within the universal joint. Contributing to the universal joint failure was the universal joint design, which was prone to galling wear and seizure.
C-172 hits power lines during low recon flight
Probable cause: The pilot’s failure to see and avoid power lines while maneuvering at a low altitude.
Improper glide path leads to crash
Probable cause: The pilot’s improper glidepath during a night approach, which resulted in impact with terrain short of the runway.
Passenger’s hat flies out of plane, hits propeller
Probable cause: The loss of engine power due to a propeller failure when the passenger’s hat exited the cockpit and impacted the three-bladed pusher propeller, separating one of the propeller blades.
Carb icing contributes to crash
Probable cause: The pilot’s failure to apply carburetor heat in conditions conducive to carburetor icing, which resulted in a partial loss of engine power during landing.
First flight after maintenance goes awry
Probable cause: The failure of the pilot, who was not a certified mechanic, to tighten the B-nut on a remotely mounted oil filter line, which resulted in oil exhaustion, a total loss of oil pressure, and a subsequent total loss of engine power.
Pilot hits wrong switch on landing
Probable cause: The pilot’s inadvertent contact with the engine control unit toggle switch during flight, which resulted in the engine shutting down.