Accident Sequence
During the initial climb after takeoff, at approximately 1,500 feet above ground level, the aircraft experienced a loud metallic-sounding explosion. Oil subsequently sprayed onto the windscreen, the engine cowling opened, and a section of the propeller departed from the airplane. The pilot maneuvered the airplane toward an open area bordered by trees. However, the airplane struck the trees, burst into flames, and then collided with terrain.
Propeller Examination
Post-accident examination of the propeller revealed that a large portion of the fracture surface displayed crack arrest positions typical of fatigue cracking. The fracture features emanated from an origin area on the camber (forward) surface of the propeller blade. Microscopic examination identified an area of corrosion around the fatigue origin, as well as sanding scratches and conversion (Alodine) coating.
Maintenance Findings
Review of the maintenance records indicated that repairs had been made to the face of the propeller blades. Additionally, the propeller blades had been "repitched" following an overhaul and conversion of the engine.