Emergency transmitter linked to Dreamliner fire

Investigators in the UK have said that the fire on a Boeing 787 Dreamliner parked at London Heathrow Airport could have been caused by the aircraft’s lithium-powered Emergency Locator Transmitter (ELT).

The initial report by the UK’s Air Accidents Investigation Branch (AAIB) said the worst of the fire damage was centred around the area where the ELT is located, at the rear of the fuselage. It has now advised all Dreamliner operators to switch off the transmitters until a full investigation is launched.

“The greatest heat damage and highest temperatures were centred on the rear fuselage,” the report said. “This… coincides with the location of the aircraft’s Emergency Locator Transmitter and its associated system wiring which is mounted internally on structure close to the aircraft skin. There are no other aircraft systems in this vicinity which, with the aircraft unpowered, contain stored energy capable of initiating a fire.”

The Ethiopian Airlines B787 had been parked for more than eight hours when the fire was detected. While admitting that the fire was “extremely rare”, the AAIB has advised that airlines make the ELT units “inert”, and that a review be conducted into the units’ safety.

Boeing said it supports the AAIB’s recommendations, which it said are “reasonable precautionary measures to take as the investigation proceeds”. The company added however, that it remains confident the 787 is safe. “We stand behind its overall integrity,” Boeing said.

The lithium-powered ELT is a beacon used to help rescue teams locate an aircraft following a crash. It is not connected to the lithium-ion battery that caused the grounding of the Dreamliner earlier this year.