National Transportation Safety Board investigators discovered a ‘fatigue cracking’ on an engine disk that caused an engine fire on an American Airlines jet at Chicago O’Hare a week ago.
Investigators said the turbine disk broke into at least four pieces as the plane reached 128 knots on the runway.
This caused a fuel fire forcing an evacuation of 169 passengers and crew.
Several people were injured in the evacuation.
"One of the fractures exhibited features consistent with fatigue cracking initiating at an internal inclusion near the forward side of the hub’s inner bore," NTSB said.
Engine maker General Electric said it had cooperated in the NTSB investigation and had found a limited number of ‘closely related’ engine parts and only one was still in service.
"We are currently working with the operator to accomplish removal of the remaining part in service," GE said.
