Waco UPF-7 N32011 accident near Jim Falls, Wisconsin

Probable cause

The blockage of the right fuel tank vent, which resulted in a total loss of engine power due to fuel starvation.

NTSB analysis

During a local proficiency flight, throughout which the pilot had the fuel selector set to its “both” position, the airplane’s engine experienced a total loss of power. The pilot was unable to restart the engine and performed a forced landing, during which the airplane's left landing gear impacted an obstacle and the airplane skidded sideways and nosed over. The pilot stated that initially he did not observe fuel leaking from either fuel tank vent after the accident. However, after he opened and resealed the tank caps, the pilot noticed fuel leaking from the right fuel tank vent, consistent with an existing fuel vent obstruction having been dislodged. Subsequent examination revealed no usable fuel in the left fuel tank and 20 gallons of fuel in the right fuel tank. A postaccident examination of the wreckage did not reveal any other anomalies that would have caused a loss of engine power.

Text from the NTSB. Open the NTSB docket for CEN12LA582 for the full record.