What happened
The incident occurred while the aircraft was maneuvering for landing. Specifically, the event took place just after the pilot engaged the electric fuel pumps while executing a turn toward the final approach segment. Shortly thereafter, a fire broke out in the area surrounding the left wheel well and the adjacent nacelle.
Despite the developing emergency, the pilot managed to bring the aircraft down on the runway. The pilot was able to evacuate the airplane without sustaining injuries. According to accounts from witnesses who observed the aftermath, the aircraft appeared to be sitting level immediately following the evacuation. However, as the fire continued to burn unchecked, significant structural damage became apparent.
The intense heat caused the fire to burn through critical structural components, specifically the left main gear area and the left main spar. Consequently, the left side of the airframe dropped. Subsequent inspection revealed that the left main gear appeared to have collapsed entirely due to the effects of the fire.
The investigation
Examination of the wreckage focused on the origin of the fire and the mechanical integrity of the fuel system. Investigators located a fractured fuel line in close proximity to the left engine-driven fuel pump. This fracture was identified as the likely source of the fuel that fed the fire.
To determine the nature of the failure, a metallurgist analyzed the separated surfaces of the fuel line. The expert concluded that the fracture did not originate during the initial tightening process of the fitting. Instead, the geometry of the broken surfaces exhibited characteristics typical of failure caused by bending loads rather than installation error.