On January 7, 2013, about 1021 eastern standard time, smoke was discovered by cleaning
personnel in the aft cabin of a Japan Airlines (JAL) Boeing 787-8, JA829J, which was parked at
a gate at General Edward Lawrence Logan International Airport (BOS), Boston, Massachusetts.
About the same time, a maintenance manager in the cockpit observed that the auxiliary power
unit (APU) had automatically shut down. Shortly afterward, a mechanic opened the aft electronic
equipment bay and found heavy smoke coming from the lid of the APU battery case and a fire
with two distinct flames at the electrical connector on the front of the case. None of the
183 passengers and 11 crewmembers were aboard the airplane at the time, and none of the
maintenance or cleaning personnel aboard the airplane was injured. Aircraft rescue and
firefighting personnel responded, and one firefighter received minor injuries.
The airplane had arrived from Narita International Airport, Narita, Japan, as a regularly scheduled passenger flight operated as JAL flight 008 and conducted under the provisions of 14 Code of Federal Regulations (CFR) Part 129.
We determined that the probable cause of this incident was an internal short circuit within a cell of the auxiliary power unit (APU) lithium-ion battery, which led to thermal runaway that cascaded to adjacent cells, resulting in the release of smoke and fire. The incident resulted from Boeing’s failure to incorporate design requirements to mitigate the most severe effects of an internal short circuit within an APU battery cell and the Federal Aviation Administration’s failure to identify this design deficiency during the type design certification process.
As a result of this investigation, we made the new safety recommendations to:
- the Federal Aviation Administration,
- the Boeing Company
- the GS Yuasa Corporation
