Incident
A newly manufactured single-engine airplane suffered a complete loss of engine power while in flight, 3.6 hours after being delivered from the factory. The commercial pilot performed a forced landing to a field. During the landing, the airplane landed hard, nosed over, and came to rest inverted.
Investigation
Examination of the engine revealed that the input fuel line to the fuel transducer was not properly torqued during the manufacturing process. The line had loosened to the point where the engine was starved of fuel. The investigation determined that an unauthorized person was allowed to torque the fuel line to the transducer during the initial engine build-up. The Team Leader failed to check the torque on the fuel line fittings, yet signed the airplane's production inspection report affirming the fittings were properly torqued.
Related Event
A similar issue occurred during the airplane's first production test flight. In that instance, the failure to follow a published procedure resulted in a loss of engine power. The test pilot was able to make a successful power-off landing to an airport. As a corrective action, the manufacturer impounded the airplane and found that the output line to the transducer was loose and weeping fuel. A Lead Inspector, instructed by the Director of Quality Assurance to re-torque all fuel lines forward of the firewall, only checked the torque on the output line to the transducer, despite recording on the Flight Squawk/Repair Record that he "re-torqued all fuel lines."