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Safety Recommendation Details

Safety Recommendation A-14-130
Synopsis: 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.
Recommendation: TO THE GS YUASA CORPORATION: Review your cell manufacturing processes to minimize or prevent defects that could affect cell safety, and ensure that your employees are properly trained to identify and eliminate these defects.
Original recommendation transmittal letter: PDF
Overall Status: Open - Acceptable Response
Mode: Aviation
Location: Boston, MA, United States
Is Reiterated: No
Is Hazmat: No
Accident #: DCA13IA037
Accident Reports: ​Auxiliary Power Unit Battery Fire Japan Airlines Boeing 787-8, JA829J
Report #: AIR-14-01
Accident Date: 1/7/2013
Issue Date: 12/1/2014
Date Closed:
Addressee(s) and Addressee Status: GS Yuasa Corporation (Open - Acceptable Response)
Keyword(s): Hazmat

Safety Recommendation History
From: NTSB
To: GS Yuasa Corporation
Date: 4/30/2015
Response: This safety recommendation is briefly mentioned in the following Federal Register comment. The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration’s (FAA) notice of proposed special conditions titled “Special Conditions: Honda Aircraft Company, Model HA-420 HondaJet, Lithium-Ion Batteries,” which was published in 80 Federal Register 19889 on April 14, 2015.

From: NTSB
To: GS Yuasa Corporation
Date: 4/8/2015
Response: We note that you are considering a number of enhancements to your manufacturing process to address issues that we identified in our report. Pending completion of the enhancements that you described, Safety Recommendation A-14-130 is classified OPEN—ACCEPTABLE RESPONSE.

From: GS Yuasa Corporation
Date: 3/3/2015
Response: -From Yoshiaki Namikawa, Special Battery and Lithium-ion Battery Division, Division Manager: We are writing in response to the NTSB's December 1, 2014, letter directing our attention to the Board's previous safety recommendation (A-14-130) to: "Review your cell manufacturing processes to minimize or prevent defects that could affect cell safety, and ensure that your employees are properly trained to identify and eliminate these defects." Please rest assured that we have done so, and both appreciate and respect the Board's observations in this regard. We also agree with the Board's finding, like that of the Japanese Transportation Safety Board, that the root cause of the internal short circuit could not be identified, and that no nexus could be found between any alleged manufacturing defect and the Boston or Takamatsu incidents. GS Yuasa has reviewed comprehensively its cell manufacturing processes. While we could not find any defect in the manufacturing process, we are committed to continuously enhancing the quality of our manufacturing processes and employee training. As the Board is aware, working cooperatively with Boeing, Thales, and regulators, GS Yuasa comprehensively redesigned the battery system on the 787 prior to the Board's final report, with increased reliability and safety. In addition, to further enhance safety of the battery, GS Yuasa is considering to make enhancements on the points where potential source of vulnerability were suggested during the NTSB investigation, regardless of whether such vulnerability was supported or established. GS Yuasa is considering safety enhancements in the following areas: (1) Cell • Reduction of perturbation in cell windings • Enhancement of strength against external stress at terminals • Introduction of edge coating, which reduces uncoated area at the current collector side of the electrode • Activities to further eliminate the possibility of FOD 1. Enhancement of cleaning procedure 2. Enhancement on stationary measurement of metallic dust 3. Enhancement on suction method of metallic dust 4. Enhancement on prevention of metallic dust 5. Further reduction of the possibility of a contamination in raw materials • Enhanced trainings on ability to identify anomalies (2) Battery • Enhancement on thermos-stability of spacer installed between cells • Enhancement on strictness of battery acceptance test We are confident that these enhancements, along with those jointly developed by the parties prior to the Board's final report and recommendations, represent sound, continuous quality enhancements to the battery system on the B787. Again, while we continue to have disagreements with various aspects of the Board's final report in this matter, particularly regarding manufacturing defects, as more fully detailed in our prior submissions to the Board, we greatly respect and appreciate the Board's investigation, findings, probable cause determination, and recommendations to the parties, including those directed to GS Yuasa. We trust the above is responsive to your recommendation, but do not hesitate to contact us in the future should you have any questions or concerns. We thank the Board and its professional staff very much for the courtesies and consideration extended to GS Yuasa during the course of the investigation.