Accident Description
A helicopter was in cruise flight at 600 feet above ground level when the engine lost power. The pilot initiated an autorotational descent. Due to rough, downhill sloping terrain, the pilot attempted to extend the glide. During this maneuver, rotor RPM decayed. At touchdown, the main rotor flexed downward and severed the tail boom.
Pilot Actions
The pilot reported that he had exhausted the helicopter's fuel supply. The autorotation was performed in response to the power loss, and the glide extension was necessitated by the terrain conditions.
Postaccident Inspection
A postaccident inspection of the helicopter revealed that less than one quart of fuel was available in the fuel cell. The pilot's statement regarding fuel exhaustion was consistent with this finding.