Incident Sequence
Following an air taxi flight, the helicopter landed at a prearranged site. The pilot signaled the three passengers to board. As the passengers attempted to board from the right side of the aircraft, the rotor blades went out of track and phase. The aircraft began an uncontrollable bouncing motion. The passengers fled the area. The helicopter then became airborne, collided with a nearby fence, and rolled over.
Examination Findings
After the accident, all five main rotor blades were found separated from the aircraft. Examination of the swash plate, strap pack, and main rotor assembly showed evidence of overload failures. No physical evidence of a rotor blade striking the fence was found independently of the event that occurred when the uncontrolled aircraft collided with the fence.