Skip Ribbon Commands
Skip to main content
Safety Recommendation Details

Safety Recommendation A-16-002
Synopsis: On July 28, 2011, about 04:11 Korean standard time, Asiana Airlines Flight 991, a B747 400F airplane on a scheduled cargo flight from Incheon, Republic of Korea, to Shanghai, China, crashed into international waters about 130 km west of Jeju International Airport. The flight crew reported a cargo fire to Shanghai Area Control Center and attempted to divert to Jeju International Airport. The two pilots aboard the flight died. The wreckage of the airplane was distributed on the sea floor at an average depth of 85 meters (m), in an area 3 km by 4 km in a southwest-northeast direction. The ARAIB determined that the cause of this accident was a fire that developed on or near two pallets containing dangerous goods packages, including hybrid-electric vehicle lithium ion batteries and flammable liquids, but no physical evidence of the cause of the fire was found. The fire rapidly grew large and uncontained, which resulted in a loss of control and some portions of the fuselage separating from the aircraft in midair, thereby resulting in the crash. The ARAIB report cited as a contributing factor the flammable materials and lithium-ion batteries that were loaded together either in the same or adjacent pallets.
Recommendation: TO THE PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTATION: Establish maximum loading density requirements that restrict the quantities of Class 3 flammable hazardous materials or Class 9 lithium batteries stowed on a single pallet or ULD, or on a group of pallets or ULDs, within an aircraft such that cargo fires can be effectively managed by on-board fire suppression capabilities.
Original recommendation transmittal letter: PDF
Overall Status: Open - Acceptable Response
Mode: Aviation
Location: Jeju Island, Korea, Republic Of
Is Reiterated: No
Is Hazmat: No
Accident #: DCA11RA087
Accident Reports:
Report #: None
Accident Date: 7/27/2011
Issue Date: 2/9/2016
Date Closed:
Addressee(s) and Addressee Status: PHMSA (Open - Acceptable Response)
Keyword(s): Hazmat

Safety Recommendation History
From: NTSB
Date: 9/21/2017
Response: On December 15, 2016, we held a teleconference with your staff and with staff from the Federal Aviation Administration (FAA) to discuss this recommendation. The FAA staff felt that, because this recommendation addresses an aircraft’s on-board fire suppression capabilities, it was the more appropriate organization to respond to Safety Recommendation A-16-2. We note from your current letter that the FAA will take primary responsibility for this recommendation and is initiating action to address it. We further note that you will update us regarding the FAA’s progress. Pending development of maximum loading density requirements that take into consideration an aircraft’s on-board fire suppression capabilities, Safety Recommendation A-16-2 remains classified OPEN--ACCEPTABLE RESPONSE.

Date: 7/14/2017
Response: -From Howard W. McMillan, Acting Deputy Administrator: I would like to extend a note of appreciation to your staff for their cooperation in discussions with PHMSA and FAA in determining the preferred path forward regarding Safety Recommendation A-16-002. FAA will take primary responsibility for this recommendation and is commencing work immediately. PHMSA will update NTSB on FAA's progress accordingly.

From: NTSB
Date: 8/18/2016
Response: We note that you concur with the intent of this recommendation and that you have been working with the Federal Aviation Administration to determine the specific actions you will take to satisfy it. Pending completion of the recommended action, Safety Recommendation A-16-2 is classified OPEN--ACCEPTABLE RESPONSE.

Date: 6/6/2016
Response: -From Marie Therese Dominguez, Administrator: PHMSA concurs with the intent of both safety recommendations to enhance the safe transportation of lithium batteries by air and shares your concerns regarding the potential for lithium batteries to initiate and contribute to the severity of a fire in the cargo compartments of aircraft in the presence of flammable liquids. The safe transport of lithium batteries by air has been an ongoing concern for PHMSA, the Federal Aviation Administration (FAA), and the U.S. Department of Transportation. PHMSA participates in a number of international forums, including the International Civil Aviation Organization (ICAO) Dangerous Goods Panel (DGP), as part of the ongoing process of harmonizing the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) with international standards and regulations and is committed to ensuring the ICAO Technical Instructions for the Safe Transport of Dangerous Goods by Air and the HMR provide a level of safety such that lithium batteries can be carried without putting an aircraft or its occupants at risk. As you stated in your letter, the ICAO DGP met in Montreal, Quebec, Canada in October 2015 to consider the development of further measures to mitigate the risks associated with the transport of lithium batteries when carried as cargo. With respect to Safety Recommendation A-16-001, temporary measures to mitigate the hazards of lithium battery transport by cargo aircraft were proposed (pending a comprehensive solution that would mitigate these hazards) to the DGP. These measures included, among others, the segregation of lithium batteries from other dangerous goods (e.g., flammable liquids). Given the complex nature of the safety problem that underlies Recommendation A-16-001, segregation or the other identified measures may or may not provide the ultimate solution to the problem. The DGP may also consider measures that are in addition to or in lieu of segregation, such as those that recognize that different operators have different mitigating tools available to them based on the size of their operation and the types of cargo compartments and fire suppressions systems available on their aircraft. Such measures would also need to provide enough flexibility to allow for the use of fire containment covers, fire resistant containers and unit load devices that could contain or suppress a lithium battery fire. PHMSA, in cooperation with the FAA, will continue to work within the ICAO DGP to address this issue during the current 2016-2017 biennium. Decisions taken by the DGP would be considered for adoption within the HMR in the earliest possible rulemaking once this work is complete. With respect to Safety Recommendation A-16-002, PHMSA has been engaged with FAA in determining the best course of action to address this recommendation. Discussions and collaboration are ongoing and we plan to provide you with a more detailed plan of action on this recommendation in a follow-up response to this letter. We note that recent measures approved by the ICAO Governing Council may provide for an alternative approach that would address the NTSB 's concerns of stowage of lithium batteries with flammable liquids. Based on recommendations from the ICAO Air Navigation Commission, as well as the Dangerous Goods, Flight Operations, and Airworthiness panels, the ICAO Governing Council approved three new measures to enhance lithium battery safety, effective April1, 2016. These measures include: (1) prohibiting the transport of lithium ion batteries as cargo aboard passenger aircraft; (2) requiring lithium ion batteries to be transported at not more than a 30 percent state of charge; and (3) limiting current provisions for small lithium batteries to no more than one package per consignment. PHMSA supports ICAO's measures and intends to incorporate these amendments into the HMR in an interim final rule anticipated for publication in September 2016. The timeline for this rulemaking may be reviewed at: In addition, the ICAO Dangerous Goods and Flight Operations panels recommended that operators conduct a safety risk assessment on the transport of dangerous goods and lithium batteries. The safety risk assessment process should include the implementation of necessary mitigation measures in order to ensure the safe transport of dangerous goods including lithium batteries as cargo on aircraft. In summary, PHMSA is engaged in a number of important actions to further ensure the safety of lithium batteries on aircraft. PHMSA will continue to coordinate with FAA through the international standards organizations in consultation with industry and research institutions to assess incident data focusing on root causes and ongoing research to gauge any necessary changes to lithium battery transport requirements. Finally, PHMSA will follow-up with the NTSB with greater detail on all of its initiatives affecting lithium battery safety with respect to Safety Recommendations A-16-001 and A-16-002 when we have collectively determined a planned course of action to further address the recommendations.