Amateur-built 260L HUMMINGBIRD N4045 accident near Harrisville, New York

Probable cause

The failure of an electric fuel pump, which resulted in fuel starvation and a total loss of engine power during cruise flight.

NTSB analysis

The commercial pilot was conducting a cross-country flight in an experimental amateur-built helicopter that was equipped with an automobile engine. When the airplane was about 6 miles from the destination and at a cruise altitude of 500 ft above ground level, the engine sputtered once and then lost all power. The pilot performed an autorotation into a low-lying valley with short trees. During the landing, the main and tail rotors contacted the trees, resulting in substantial damage.

Postaccident testing revealed that one of the two electric fuel pumps did not operate when direct current was applied to it, indicating that the pump had failed during flight. According to the manufacturer, both fuel pumps are to be used for takeoff and landing, but only one fuel pump is necessary during cruise flight. The pilot was using one fuel pump during cruise flight, and the fuel pump that failed was likely the one in use at the time. The fuel pump failure resulted in fuel starvation and a subsequent total loss of engine power.

Text from the NTSB. Open the NTSB docket for ERA18TA076 for the full record.