The United States Federal Aviation Administration (FAA) issued a Special Airworthiness Information Bulletin (SAIB), advising aircraft operators against the dangers of potential uncontrolled fires in the cargo compartment.
“Multiple accidents have occurred over the last few decades demonstrating an elevated risk when carrying certain quantities of hazardous materials, such as flammable aerosols, gases, solids and explosives, and lithium batteries,” the FAA noted, adding that while there are regulations that address the transportation of hazardous materials, they “do not address the aircraft-level risk posed by an aggregate shipment of these items”.
While the condition is not considered unsafe enough to warrant an Airworthiness Directive, the FAA has issued the SAIB in response to safety recommendations (SR) issued by the National Transportation Safety Board (NTSB) following three accidents caused by fires in the cargo hold.
The NTSB, which issued the recommendations in November 2012, highlighted three separate accidents involving a UPS Airlines McDonnell Douglas DC-8F, a Boeing 747-400F, and an Asiana Cargo Boeing 747-400F. While the crew members of the DC-8F survived and were later treated for smoke inhalation, the pilots of both 747-400Fs suffered fatal injuries once the aircraft impacted the ground.
According to an FAA summary of the three SRs, the recommendations have been implemented to improve the early detection of fires in the cargo compartment, improve the fire resistance of cargo containers and covers, and require active fire suppression systems in all cargo holds.
“Airframe manufacturers have also recognized a potential incompatibility with cargo compartment fire protection systems and the type of cargo being carried. For more information, Boeing operators may reference Boeing Multi Operator Message MOM-MOM-15-0469-01B, dated July 17, 2015; and Airbus operators may reference Airbus In-Service Information 00.00.00182, dated July 24, 2015,” the FAA noted.
The agency also said that it expects “operators to understand the capabilities and limitations of aircraft cargo compartments and to consider this information when deciding what to load in those compartments”. Still, while it collaborates with various industry stakeholders to find the best practices to prevent fatal cargo fire compartment fires, the FAA issued seven interim recommendations to airlines that carry cargo:
- Retain or include Class C cargo compartments on freighter aircraft that by design provide more “protection against re-ignition during descent and may contribute to reducing fire temperatures by limiting the involvement of materials”.
- Perform assessment risks specific to cargo, in particular, when carrying items with lithium, such as batteries.
- Consider the cargo safety information previously provided by the FAA.
- Usage of fire-resistant containers (FRC).
- Usage of fire containment covers (FCC).
- Participate in industry-wide forums to “develop standards or to stay apprised of the development stages of future cargo fire safety risk controls”.
- Consider the safety enhancements put forward by the Commercial Aviation Safety Team (CAST).