What happened
During the landing roll, a fire erupted in the right engine of the aircraft. Once the airplane had come to a complete stop on the runway, the engines were shut down and the occupants successfully evacuated the aircraft.
The investigation
Investigators examined the fuel/oil heat exchanger to determine the source of the leak. They discovered that one of the three studs used to secure the fuel filter to the heat exchanger had pulled out of its housing. This failure allowed fuel to spill into the engine bay, where it made contact with hot engine surfaces, resulting in the fire.
The component involved had accumulated approximately 1,000 hours of operation since its last overhaul. Upon inspection of the unit, investigators found that the stud had pulled out of an oversized lug hole.
Furthermore, a review of the manufacturer's overhaul manual indicated that there was insufficient information regarding the procedures for working with the lug holes. Specifically, the manual lacked adequate instructions on how to ensure the holes were properly drilled and how to verify that the studs were correctly inserted into the holes.