Accident Sequence
The airplane experienced a loss of engine power shortly after takeoff, forcing the pilot to land in a corn crop. The pilot reported that earlier on the day of the accident, during a previous flight, he noticed an odor of fuel but could not identify the source. The airplane operated normally with normal fuel flow on that flight. During the subsequent flight, the pilot again detected fuel odor, and while climbing through 3,000 feet, the engine lost power. The pilot was unable to restart the engine. After landing in the corn field, smoke entered the cabin.
Post-Accident Inspection
A post-accident inspection of the engine revealed that the nozzle pressure port plug on the aft side of the fuel manifold valve was not in place and was not located. Blue fuel stains were evident under the left magneto and on the engine case under the right cylinders. The plug hole and the surrounding area showed no evidence of torque putty (Loctite) having been applied when the plug was installed. In contrast, the injector line fittings and the fuel inlet fitting had torque putty applied.
Engine History and Manufacturer Response
The engine had operated 10.1 hours since it was overhauled. Continental Motors, the engine manufacturer, reviewed their build-up procedures for the IO-550 engines and determined that the requirement for applying Loctite to the suspect fitting had been removed from the procedures. In response, Continental Motors issued a Quality Alert re-inserting the requirement for Loctite to be applied to the nozzle pressure port plug during installation. Additionally, the procedures manual and build-up instructions for the IO-550 were revised to include the requirement for Loctite application to the plug.