Dreamliner fire probe finds beacons should be switched off

The emergency locator beacons in Boeing Dreamliners should be switched off after being identified as the most likely origin of a recent fire on a parked jet, British investigators said today.

The beacons, made by US conglomerate Honeywell, are positioned in the upper rear part of the new, advanced jets, and send a signal that leads rescuers to downed aircraft. They are powered by non-rechargeable lithium-manganese batteries.

Britain's Air Accidents Investigation Branch (AAIB), which is leading the investigation into a blaze that broke out on a parked Ethiopian Airlines jet at London's Heathrow airport last Friday, also said aviation regulators should conduct a safety review of lithium-powered emergency locator beacons in all aircraft types.

Its report, published today, said the fire occurred in the upper portion of the Dreamliner’s rear fuselage where the emergency locator transmitter (ELT) devices are located.

No other system in this part of the plane contained stored energy capable of causing such a fire while the plane was unpowered, the British agency said.

Boeing said it supported the AAIB’s two recommendations. “The two recommendations ... are reasonable precautionary measures to take as the investigation proceeds,” Boeing said in a statement.

The US planemaker reiterated its confidence in the Dreamliner’s safety and said it stood by the plane’s “overall integrity”.

The AAIB recommended that the US Federal Aviation Administration ensure the power is turned off in all Honeywell-made ELT systems in the 60 plus Dreamliners currently in commercial service. A source close to the probe said this could mean removing the ELT’s batteries.

The battery linked to the London fire is made by New York-based Ultralife Corp, according to an industry source. Honeywell and Ultralife were not immediately available for comment.

Reuters