The failure of a tube inside the nr.2 engine of a Japanese MD-90 caused an oil leak and resulting engine fire, according to an investigation by the Japan Transport Safety Board (JTSB).
On Sunday August 15, 2010, a McDonnell Douglas MD-90-30, registered JA002D, operated by Japan Airlines took off from Sendai Airport for Fukuoka Airport as a scheduled flight JL3538. Around 16:10, while climbing, it declared a state of emergency upon the activation of the right engine fire warning alarm at about 5,500 ft. The right engine was shut down while the fire-extinguishing system was activated; consequently, the aircraft returned to Sendai Airport and it landed at 16:23. Heat damage inside the cowling of the right engine was confirmed after landing.
There were 111 people on board but no one was injured.
The JTSB concluded that it was “probable that this serious incident occurred as follows: The Aircraft No. 4 Bearing Scavenge Tube of the right engine fractured during takeoff, resulted in the Tube breaking loose from the Diffuser Case letting the engine oil blow out through an opening where it broke loose, and subsequently the oil contact with the engine high temperature section developed into an engine fire. It is highly probable that the repeated stress associated with engine operations generated the crack origins in the No.4 Scavenge Tube and the fatigue crack grew into the fracture of the tube. ”