The July 12 fire aboard an Ethiopian Airlines Boeing 787 at London Heathrow Airport (ELHR) has prompted the UK Air Accidents Investigation Branch (AAIB) to recommend operators turn off Honeywell’s Rescu 406 AFN emergency locator transmitters (ELTs) aboard the Dreamliner until appropriate airworthiness actions can be completed. The 787 fire at Heathrow broke out above the ceiling in the rear cabin while the unoccupied aircraft was plugged into ground power.
The AAIB said that while a thermal incident such as the July 12 fire is rare, airliners do not carry equipment in the ceiling area where the ELT is mounted to detect or suppress a fire. The AAIB recommended the FAA and other regulatory bodies conduct a thorough investigation into the lithium battery-powered ELTs and issue airworthiness action if appropriate. The FAA said on July 19 that it will order inspections of ELT wiring, as well as requiring operators to inspect the battery compartment for signs of heating or moisture.
In a statement, Boeing said it “supports the two recommendations from the UK Air Accidents Investigation Branch, which we think are reasonable precautionary measures to take as the investigation proceeds.”