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On January 7, 2013, smoke was discovered by cleaning personnel in the aft cabin of a Japan Airlines Boeing 787-8, JA829J, which was parked at a gate at General Edward Lawrence Logan International Airport, Boston, Massachusetts. About the same time, a maintenance manager in the cockpit observed that the auxiliary power unit (APU)—the sole source of airplane power at the time—had automatically shut down. Shortly afterward, a mechanic opened the aft electronic equipment (E/E) bay and found “heavy smoke” and a “small flame” coming from the APU battery case.1 No passengers or crewmembers were aboard the airplane at the time, and none of the maintenance or cleaning personnel aboard the airplane was injured.
TO THE FEDERAL AVIATION ADMINISTRATION: After Safety Recommendation A-14-032 has been completed, require aircraft manufacturers to perform the tests and demonstrate acceptable performance as part of the certification of any new aircraft design that incorporates a permanently installed, rechargeable lithium-ion battery.
Original recommendation transmittal letter:
Open - Acceptable Response
Boston, MA, United States
Auxiliary Power Unit Battery Fire Japan Airlines Boeing 787-8, JA829J
Addressee(s) and Addressee Status:
FAA (Open - Acceptable Response)
Safety Recommendation History
We note that SC-225 included lithium-ion battery technology experts from government and test standards organizations. Your use of these experts is more fully addressed by Safety Recommendation A-14-36, which was not discussed in your September 20, 2018, letter. We hope to receive your response to that recommendation soon. We further note that you are revising Advisory Circular (AC) 20-184, “Guidance on Testing and Installation of Rechargeable Lithium Battery and Battery Systems on Aircraft,” to note that RTCA DO-311A is one means of complying with the special conditions regarding rechargeable lithium-ion battery systems. Until the revised AC is released, you will use issue papers to inform applicants of the effects of battery cells going into thermal runaway, and all current certification projects involving permanently installed lithium-ion batteries will use RTCA DO-311A and RTCA DO-347, “Certification Test Guidance for Small and Medium Sized Rechargeable Lithium Batteries and Battery Systems,” as a means of compliance. Pending the release of the revised AC, Safety Recommendations A-14-33 and -34 remain classified OPEN--ACCEPTABLE RESPONSE.
-From Daniel K. Elwell, Acting Administrator: The Federal Aviation Administration (FAA) agrees that consistent and standardized test methods are necessary to facilitate certification of new aircraft designs that incorporate a permanently installed rechargeable lithium- ion battery. For new transport airplane certification projects, the FAA issues special conditions for applicants whose designs include rechargeable lithium-ion or other lithium based batteries. These special conditions provide adequate certification standards. The FAA worked with RTCA to approve a revision to RTCA 00-3 11 , Minimum Operational Performance Standards for Rechargeable Lithium Battery Systems, for large battery systems. On December 19. 2017, the RTCA released RTCA 00-3 11 A, which contains abuse tests that subject a single cell within a permanently installed, rechargeable lithium-ion battery to thermal runaway and demonstrate that the battery installation mitigates all hazardous effects of propagation to other cells and release of electrolytes, fire. or explosive debris outside the battery case. The tests will replicate the battery installation on the aircraft and be conducted under conditions that are considered to produce the most severe outcome. The FAA incorporated RTCA 00-311 A into the revision of Technical Standard Order (TSO)-C 179a. Permanently Installed Rechargeable Lithium Cells, Batteries and Battery Systems. TSO-C l79b was released on March 23. 2018 and is available at the following website: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgTSO.nsf/0/67 FF4FD73B2DEF078625825F00716B87?0pen0ocument. On October 15, 20 1 5, t he FAA issued Advisory Circular (AC) 20-184, Guidance on Testing and Installation of Rechargeable Lithium Battery and Battery Systems on Aircraft. to provide guidance for complying with the special conditions to meet the installation, operation, maintenance, and airworthiness requirement s for installation of lithium batteries on aircraft. AC 20- 184 invokes RTCA 00-31 1 and RTCA 00-347. Certification Test Guidance for Small and Medium Sized Rechargeable Lithium Batteries and Battery Systems, and also provides guidance on how to obtain installation approval for permanently installed rechargeable lithium-ion batteries and battery systems on aircraft. The FAA is revising AC 20-184 to invoke RTCA D0-31lA as one means of compliance to the special conditions regarding rechargeabe lithium-ion battery systems. Until the AC 20-184A revision is released, the FAA will utilize issue papers to inform applicants of the effects of battery cells going into thermal runaway. In the meantime, all current projects will utilize RTCA D0-31 l A and RTCA 00-347 as a means of compliance. The 17AA expects the revised AC 20-184A to be released in December 2018. The FAA is reviewing the in-service performance and methods of compliance used to certify permanently installed rechargeable lithium-ion batteries on in-service aircraft to determine design/installation and certification details. This review, supplemented by a review of service difficulties, has not yet identified a need for corrective airworthiness action. We will continue to monitor permanently installed rechargeable lithium-ion battery system performance as part of our normal continued operational safety processes.
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. As the FAA states in its notice, the applicable airworthiness regulations contained in 14 Code of Federal Regulations Part 23 do not include adequate or appropriate safety standards for the HondaJet’s installation of lithium-ion (Li-ion) batteries, which possess certain failure, operational characteristics, and maintenance requirements that differ significantly from that of nickel cadmium and lead acid rechargeable batteries. The proposed special conditions contain the additional safety standards that the FAA administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. In 2014, in connection with our investigation of the January 7, 2013, auxiliary power unit Li-ion battery fire on board a Japan Airlines Boeing 787, the NTSB issued two sets of safety recommendations (A-14-32 through -36 and A-113 through -127) to the FAA addressing Li-ion batteries to be used on transport-category airplanes, which are subject to Part 25 regulations, and the certification of new technology. The safety intent of these recommendations also apply to Li-ion battery installations in general aviation airplane types such as the HondaJet. We believe that the proposed special conditions are generally adequate but that proof of their effectiveness is in the applicants’ methods of compliance. The NTSB notes that some of the special conditions need more detail to promote an equivalent level of safety, as intended. For example, proposed paragraph e states “no corrosive fluids or gasses that may escape from any Li-ion battery may damage surrounding airplane structure or adjacent essential equipment.” The NTSB believes that this special condition should explicitly indicate electrical wiring in the list of items that could be damaged. During the investigations of the 787 events, damage to wiring, in addition to structure and equipment, was observed. Proposed paragraph f states that the applicant must provide provision for each installed Li-ion battery to prevent any hazardous effect on structure or essential systems that may be caused by the maximum amount of heat the battery can generate during a short circuit of the battery or of its individual cells. The NTSB believes that provisions must be established to prevent hazardous effects from the maximum heat generated during a battery failure event, regardless of failure mode. Short circuits, as a general class of abuse, can vary in severity and may not represent a worst case scenario. Proposed paragraph g states that Li-ion battery installations must have the following: (1) A system to control the charging rate of the battery automatically so as to prevent battery overheating or overcharging; or (2) A battery temperature sensing and over-temperature warning system with a means for automatically disconnecting the battery from its charging source in the event of an over-temperature condition; or (3) A battery failure sensing and warning system with a means for automatically disconnecting the battery from its charging source in the event of battery failure. The NTSB believes that “and” should replace “or” between subparagraphs (1) and (2) as well as between subparagraphs (2) and (3). Further, consistent with Safety Recommendations A-14-115 and -116, paragraph g should include a provision for monitoring temperatures and voltages at the individual cell level throughout the operating temperature range. This monitoring is to ensure that battery installations prevent hazardous conditions resulting from overcharge but also mitigate the severity of failure conditions that cannot be prevented exclusively via charging controls such as exposure to excessive temperature in operation or internal short circuiting. Such a modification to the proposed language would reflect a level of safety equivalent to Li-ion installations in transport-category aircraft, which the NTSB believes is also appropriate for Part 23 aircraft such as HondaJet. Additionally, subparagraphs (2) and (3) are more likely to identify problems after they occur, whereas subparagraph (1) is more preventive. Proposed paragraph j states “batteries in a rotating stock (spares) that have experienced degraded charge retention capability or other damage due to prolonged storage must be functionally checked at manufacturers’ recommended inspection intervals.” The NTSB notes that recent special conditions for transport-category aircraft state that “the instructions for continued airworthiness must also contain procedures for the maintenance of batteries in spares storage to prevent the replacement of batteries with batteries that have experienced degraded charge retention ability or other damage due to prolonged storage at a low state of charge.” We believe the proposed special conditions should be revised to include provisions for preventive maintenance while in storage, where appropriate, to highlight the potential risk of installing an improperly maintained battery in an aircraft even if it passes the functional checks, which could lead to a thermal runaway condition in operation due to preexisting, undetectable damage. The NTSB notes that another set of recent special conditions for transport-category aircraft included the provision that “precautions should be included in the Instructions for Continued Airworthiness maintenance instructions to prevent mishandling of the rechargeable lithium-ion batteries and battery systems, which could result in short-circuit or other unintentional impact damage caused by dropping or other destructive means.” The proposed special conditions for the Model HA-420 HondaJet do not include this provision. We believe that a similar provision should be added to provide an equivalent level of safety for all Li-ion batteries and installations for all categories of aircraft. Finally, as reflected in Safety Recommendations A-14-32 and A-14-33, we believe that applicable tests should replicate the battery installation on an aircraft and be conducted under conditions that produce the most severe outcome. As the FAA determines compliance with the special conditions, please ensure that these recommendations are taken into account. In closing, the NTSB would like to stress the importance of thoroughly assessing the risks of internal short circuiting in approving applicants’ methods of compliance. We appreciate the opportunity to comment.
From the report number AIR-14-01 concerning the January 7, 2013, incident, involving a battery fire Japan Airlines Boeing 787-8, JA8297, at Boston Logan International Airport: As stated in section 1.8.2, the NTSB issued Safety Recommendations A-14-32 through -36 to the FAA regarding (1) insufficient testing methods and guidance for addressing the safety risks of internal short circuits and thermal runaway and (2) the need for outside technical knowledge and expertise to help the FAA ensure the safe introduction of new technology into aircraft designs. On August 19, 2014, the FAA responded to these recommendations. In its response letter, the FAA stated that it has been working with RTCA Special Committee SC-211 to revise RTCA document DO-311, “Minimum Operational Performance Standards for Rechargeable Lithium Battery Systems,” to “capture all the enhancements and lessons learned” from the BOS incident, including the need for a test that subject a single cell within a lithium-ion battery to thermal runaway as a result of an internal short circuit. The FAA also stated that, until these revisions are completed, it would use the issue paper process to provide new design applicants with acceptable methods of compliance for conducting tests and analyses to address the potential failure effects of permanently installed, rechargeable lithium-ion batteries. The FAA further stated that it was surveying previous approvals of rechargeable lithium battery systems to determine those existing approved designs that require additional testing and/or analysis to ensure that they can mitigate all adverse effects of a cell thermal runaway. In addition, the FAA stated that it was setting up meetings with internal stakeholders to determine how best to implement Safety Recommendation A-14-36. The NTSB is encouraged that the FAA is taking steps to enhance RTCA document DO-311 but is concerned that aircraft installation factors might not be addressed in the document given that DO-311 is a battery-level standard. On the basis of the FAA’s actions, the NTSB classifies Safety Recommendations A-14-32 through -36 OPEN--ACCEPTABLE RESPONSE pending review of future updates regarding the FAA’s progress in completing the recommended actions.
-From Michael P. Huerta, Administrator: The FAA requires that applicants whose designs include rechargeable lithium-ion or other lithium-based batteries comply with the Installed Rechargeable Lithium Batteries and Rechargeable Lithium-Battery Systems special conditions. The FAA believes that these special conditions, which were applied to the B-787 and other aircraft and models modified during recent certification programs, provide adequate certification standards. The FAA is working with industry stakeholders to update the test standards provided in RTCA D0-311 to include lessons learned from the B-787 incident. This includes specific testing and design considerations for the effects of thermal runaway. propagation from one cell to another, release of electrolyte, fire, or explosive debris outside the battery case. and other potential failure effects. Pending finalization of the revision to RTCA D0-311, the FAA is using the issue paper process for new designs. The issue paper process provides new applicants with acceptable methods of compliance for conducting tests and analysis to address the potential failure effects noted above, and for demonstrating compliance with the installed Rechargeable Lithium Batteries and Rechargeable Lithium Battery Systems special conditions.
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