Accident Narrative
According to multiple witnesses, after departing the airport, the helicopter turned to the north and climbed to an altitude reported as low as 100 feet above ground level and as high as 800 feet above ground level. As it approached the accident site location, the helicopter's tail reportedly lowered, it slowed, rotated or turned slightly to the east, and then descended rapidly toward the terrain. Witnesses reported that near the beginning of the descent, the main rotor blades either slowed their rotation significantly or "stopped turning." One witness stated that almost immediately after observing the change in rotation speed of the main rotor blades, "…the helicopter just dropped out of the sky."
Wreckage Examination
Examination of the wreckage disclosed evidence of coning of the main rotor blades. No evidence was found of any flight control malfunction or loss of engine power.