An initial nose-pitch-up event and out-of-trim condition, the reason for which could not be determined because the examinations of the airplane did not reveal any anomalies that would have precluded normal operation. Contributing to the accident was the pilot’s failure to use the manual trim wheel to reset the pitch trim.

The pilot's improper landing flare in gusting wind conditions resulting in a collision with an airport sign.

Fracture of the #4 connecting rod for undetermined reasons, which resulted in a loss of engine power. A factor was the forced ocean ditching.