Page:NTSB Report, Japan Air Lines Flight 813.pdf/21

- 18 - 9. The inflignt fire, lack of fire warning to the crew and the hydraulic dlfficulty were direct results of the engine fallure.

10. The normal tight fit of the torque mug and restrainng effect of the borescope inspectlon port plugs kept the torque mug in place during the tune between the engine overhaul and the engine failure.

11. Weather was no factor in the accident.

(b) Probable Cause

The Board determines that the probable cause of the accident was a disintegrating engine failure and inﬂight, fire caused by the failure of maintainence personnel to properly secure the low pressure compressor section torque ring during engine overhaul.

BY THE NATIONAL TRANSPORTATION SAFETY BOARD:

/s/ JOSEPH J. O'CONELL, Jr. Chairman

/s/ OSCAR M. LAUREL Member

/s/ JOHN H. REED Member

/s/ LOUIS M. THAYER Member

/s/ FRANCIS H, McADAMS Member