What happened
During a flight following the loading of 65 gallons of Jet-A fuel, the pilot reported a complete loss of engine power to air traffic control. The incident occurred after the aircraft had reached a leveled altitude of 7,000 feet. Prior to the power loss, the pilot had noted no irregularities during the initial engine start or the takeoff phase. In an attempt to restore power during the subsequent descent, the pilot performed both battery and air-based engine restart attempts, but neither procedure was successful.
Findings
An inspection of the engine, performed on November 30, 2005, revealed mechanical issues within the accessory gearbox. Investigators identified a reddish-brown stain located under the fuel control unit and fuel pump. Upon removing the fuel pump unit, further discoloration was noted in the area between the pump and the gearbox.
Technical examination determined that the drive splines within the fuel pump were worn, and the internal splines on the fuel pump drive coupling also showed significant wear. This degradation of the spline drive and coupling prevented the components from achieving full engagement. Additionally, evidence of fretting and reddish-brown material was present on both components. At the time of the incident, the engine had a total time of 9,852 hours, with 5,574 hours since its last overhaul. The aircraft had operated for approximately 130 hours since its previous maintenance inspection, which had included a check of the fuel pump.