Piper PA-28R-200 N55641 accident near Gillette, Wyoming

Probable cause

A loss of engine power due to fuel starvation resulting from a loose B-nut at the engine-driven fuel-pump inlet.

NTSB analysis

Shortly after takeoff, the pilot smelled fuel and the engine began to lose power. The pilot initiated a turn back toward the airport, but the airplane was unable to maintain altitude. The airplane touched down in a field and collided with a fence.

The airplane had undergone maintenance a few days before the accident, which included repositioning the fuel line to the engine-driven fuel pump. A postaccident examination revealed that the B-nut securing the fuel line at the pump inlet was loose and could be rotated approximately one-half turn by hand before the fitting came off. Visible fuel staining and spray residue were present in the area of the pump inlet. The manufacturer’s specified torque specification for the aluminum-alloy fitting was 75 to 125 inch-pounds. The loss of engine power was consistent with fuel starvation due to the loose fitting, allowing air ingestion and interrupting normal fuel delivery.

Text from the NTSB. Open the NTSB docket for WPR25LA046 for the full record.