The Incident
On May 6, 2013, a Bombardier CL-600-2B19, registration JA206J, operated by J-AIR Corporation, departed Oita Airport as Japan Airlines scheduled flight 2362 and landed on runway 32R at Osaka International Airport at 12:14 JST. While taxiing on taxiway A4, at approximately 12:15, a caution message for a right engine fire detection system failure appeared, followed by a warning message for a right engine fire. The flight crew, consisting of a captain and a copilot, responded by shutting down the right engine and selecting the engine fire push switch. The aircraft continued taxiing and entered parking spot No. 19 at 12:18. There were 55 persons on board, including the captain, two crew members, and 52 passengers. No injuries were reported.
Investigation
The Japan Transport Safety Board (JTSB) conducted an investigation with participation from Canada and the United States, as states of design and manufacture. During post-flight maintenance, evidence of fire was found within the engine fire zone. Examination revealed that a coupling nut connecting the No. 14 fuel injector to the fuel manifold on the right engine was loose. Fuel had leaked from this connection and was likely ignited by engine heat, resulting in a fire in the designated fire zone.
Probable Cause
The JTSB determined that it is highly probable that the cause of the serious incident was the loose coupling nut allowing fuel leakage and subsequent ignition. The board could not ascertain why the nut had loosened, though insufficient tightening force was considered a possible factor.
Recommendations
The JTSB issued recommendations to IHI Corporation, the engine overhaul provider, to ensure proper tightening of coupling nuts during overhauls, and to J-AIR Corporation to enhance training on safety-critical systems and emergency response to fires.