Fokker DR1 N512FH accident near Wake, Virginia

Probable cause

A total loss of engine power due to fuel starvation as the result of the improper installation of the ram air fuel vent tube, which resulted in the tube separating from the airplane during taxi and subsequent negative pressure inside the fuel tank.

NTSB analysis

The pilot departed in the experimental airplane for a local flight. While in cruise flight about 25 minutes after departure, the engine lost all power. When his attempts to restore power were unsuccessful, he performed a forced landing to a field, during which the airplane impacted power lines, landed in the field, nosed over, and came to rest inverted. The airplane sustained substantial damage to the top wing and forward fuselage.

The day after the accident, the pilot found the copper ram-air fuel vent tube on the taxiway between the hangar and the runway. The tube had electrical tape wrapped around the mounting end, presumably installed to increase its diameter to fit the larger diameter rubber tubing of the fuel tank vent line where it was previously attached and held in place by a hose clamp. The pilot surmised that the electrical tape had deteriorated due to contact with fuel, allowing the tube to separate from the rubber vent line. He further surmised that the fuel tank was insufficiently vented during the flight due to missing ram air tube, and the negative pressure in the fuel tank after 25 minutes of flight resulted in fuel starvation to the engine. The engine was successfully started and run after the accident during the examination performed by the pilot and his mechanic.

Text from the NTSB. Open the NTSB docket for ERA21LA005 for the full record.