What happened
During an instructional solo cross-country flight, approximately 1 hour and 25 minutes after takeoff, the engine of the helicopter lost power. The pilot reported that after experiencing two brief decreases in rotor RPM from the normal operating range, he decided to land the aircraft. While descending for landing, the engine began losing power at an altitude of 1,000 feet MSL. A witness observed the aircraft at an estimated altitude of 1,500 feet, noting that the engine was cutting in and out and the aircraft was yawing.
In the attempt to perform an autorotational landing, the helicopter impacted trees. There were no injuries reported following the accident.
The investigation
FAA inspectors examined the accident site and found no evidence of a fuel spill. Upon inspection of the fuel system, a total of one cup of fuel was drained from both fuel tanks, and approximately one ounce of fuel was recovered from the gascolator.
Prior to departure, the flight instructor and the pilot—an airline transport rated pilot undergoing instruction for a helicopter rating—had visually checked the fuel levels. The flight instructor estimated that there were 25 gallons of fuel on board at the time of departure. According to the manufacturer, the fuel consumption rate for this aircraft is between 12 and 14 gallons per hour.