Incident Details
A helicopter conducting controlled burn operations using a long line to spray jellied fuel experienced an engine failure while flying just above tree tops at an altitude of approximately 75 feet above ground level. The pilot initiated an autorotation toward the nearest clearing. However, the helicopter struck trees before reaching the clearing, resulting in a hard landing on the edge of the clearing.
Pilot Report
The pilot reported that the engine failure was consistent with fuel exhaustion. At the time of the incident, the helicopter had been operating for 40 minutes, and the initial fuel supply on board was sufficient for 1.5 hours of flight. The pilot's statement suggests a discrepancy between the expected fuel endurance and the observed flight time.
Investigation Findings
Subsequent examination of the helicopter revealed that the fuel tank vent was clogged. The blockage consisted of dirt from an insect nest and insect parts. The clogged vent may have prevented proper fuel flow or tank pressurization, potentially affecting engine performance.
No further causal factors were identified in the investigation. The helicopter's type, registration, and operator details were not specified in the source. No occupant injuries or fatalities were reported.