Mcdonnell Douglas Helicopter 600N N609RP accident near Eagle Lake, Texas

Probable cause

The operator’s improper installation of the fuel system, which resulted in fuel starvation, a loss of engine power, and impact with terrain.

NTSB analysis

The operator was providing flight services to law enforcement for training purposes at the time of the accident. The pilot stated that during the last flight of the evening, he flew the helicopter at a low altitude and at a low airspeed when the helicopter exhibited low rotor rpm. The helicopter lost partial engine power, and the pilot performed a forced landing. The helicopter was destroyed by impact forces.

Postaccident examination of the helicopter revealed the helicopter’s fuel system was incorrectly installed and drew fuel from the forward portion of the left fuel cell, allowing air to be drawn into the fuel system when the fuel level reached an unsustainable level for engine operation. A correct installation of the fuel system would have had fuel being drawn from the aft portion of the left fuel tanks, which had about 19.5 gallons of fuel available.

Maintenance entries showed that the pilot, who was also a mechanic, performed recent maintenance within the left fuel cell and such maintenance would have required the pilot to remove and visually inspect the fuel system components within the left fuel cell that were found to be improperly installed. The improper installation resulted in the fuel system not scavenging the available fuel from the aft portion of the left fuel cell.

Text from the NTSB. Open the NTSB docket for CEN24LA271 for the full record.