What happened
During the approach to Chongqing-Baishiyi Airport at approximately 21:50 local time, the aircraft's number four engine experienced a mechanical failure. Seven minutes after the initial engine malfunction, an intense fire erupted in the engine compartment, which eventually caused the unit to separate from the wing.
Recognizing that the destination airport was no longer reachable, the pilot attempted to perform an emergency landing. During this maneuver, the aircraft collided with power lines and struck a hillside roughly 5.7 km before reaching the runway. The impact caused the airframe to break apart and ignited a large fire. There were 108 fatalities among the passengers and crew.
Findings
Investigations into the accident concluded that the sequence of events began when the right starter generator on the number four engine reached extreme temperatures. This intense heat caused the failure of the feathering oil tube. When the propeller was feathered, the compromised tube ruptured, leading to the subsequent engine fire and detachment.