What happened
On December 8, 2010, an Air France Boeing 777-228ER, registration F-GSPK, was operating a scheduled international passenger flight from Atlanta Hartsfield to Paris Charles de Gaulle. While cruising at FL 308 over the Atlantic Ocean, cabin crew members detected the smell of an electrical fire near seat 4F in the business class cabin.
Upon investigating, the crew deactivated the power supply to the video system and removed the seat upholstery, discovering active flames. A crew member extinguished the fire by applying water to the flames. Following the intervention, the crew monitored the area for any reignition, and the flight continued to its destination without further incident.
The investigation
Investigators examined the seat structure and discovered a heavily damaged external lithium-polymer (Li-Po) battery, likely belonging to a passenger's electronic device, lodged within a seat mechanism. X-ray analysis revealed that the battery's active elements and control circuits had been destroyed.
The investigation established that the battery had slipped into a track within the seat's convertible mechanism. The physical pressure from the mechanism crushed the battery, causing an internal short circuit and a subsequent rise in temperature. This led to the exposure of the lithium electrodes to oxygen, triggering the combustion.
Findings
- The primary cause of the fire was the crushing of a lithium-polymer battery within the seat's mechanical components.
- The crew's decision to cut power to the video system prevented the fire from spreading to other electrical components in the seat.
- While the use of water successfully extinguished the flames and cooled the battery in this instance, the investigation noted that applying water to lithium fires can potentially trigger the release of flammable hydrogen gas.
- At the time of the event, the airline's operating manual did not contain specific instructions regarding lithium battery fires, and there was a lack of harmonized international regulations regarding the risks of lithium batteries in passenger electronic devices carried in the cabin.
Safety action
Following the incident, the BEA issued a recommendation to EASA to evaluate the risks associated with lithium battery fires from portable electronic devices carried in the cabin and to propose appropriate emergency procedures.