Incident Overview
While descending to 6,000 feet, the pilot encountered a complete loss of engine oil supply. The windscreen became covered with oil, forcing the pilot to use the side window to maintain forward visibility. After completing the emergency landing checklist, the engine seized.
Emergency Landing
The pilot selected an emergency landing area. During the approach, the airplane collided with a tree approximately 10 feet above the ground. After impact, the aircraft continued for about 200 feet before coming to a stop in an upright position.
Post-Crash Examination
A post-crash examination determined that the propeller assembly had separated from the engine propeller shaft. Fracture analysis of the bolts disclosed that four bolts had failed in fatigue.
Propeller Overhaul Details
The propeller had been overhauled approximately 12 hours before the mishap. During the overhaul, the facility reused the old bolts after performing magna-flux inspection and plating. The installation torque of the bolts was not determined.