WASHINGTON (AP) — Airlines should inspect the emergency locator transmitters of all Boeing 787 "Dreamliners," the Federal Aviation Administration urged Friday following a fire earlier in the week aboard one of the airliners while parked at London's Heathrow Airport.
British aviation authorities, who are investigating the fire, said the transmitters should be disabled after finding that one of the squat orange boxes was the only thing with enough power to start a fire in the plane's tail section, which was scorched.
The FAA made no mention of disabling the transmitters in a brief statement provided to the media. Instead, the agency said that after reviewing the British investigators' recommendations, U.S. officials have begun working with Boeing to develop instructions for how airlines should conduct the inspections.
The inspections would ask airlines to examine for proper wire routing, damage or pinching, and to inspect the transmitter's lithium battery compartment for heat or moisture, the statement said.
An order making the inspections mandatory for U.S. operators is expected in the coming days, the FAA said.
FAA safety orders apply only to operators of U.S. registered planes, but aviation authorities in other countries are expected to follow suit.
Boeing has delivered 68 of the planes worldwide so far, all with the same transmitter made by Honeywell International Inc. United Airlines is the only U.S. operator of the planes, with six.
Britain's Thomson Airways, which has six 787s, said on Thursday that it had already removed the emergency locator transmitters from its 787s. It said its 787 flights would still operate as planned. "This is not a Boeing 787 technical issue," the airline said, but an issue with the transmitter made by Honeywell.
Honeywell reported financial results on Friday. An analyst asked CEO David Cote how it would be possible for such a relatively small transmitter to cause a fire like the one in the 787 at Heathrow. Cote didn't answer directly, but said he wants to wait and see what the final investigation finds.
"We'll just wait to find out what actuals are, and respond to it then," he said. "There's no significant financial impact to Honeywell in any way."
British investigators have said it is not clear if the fire was caused by the transmitter's lithium-manganese dioxide batteries or a short near or around the transmitter. A spokeswoman for the investigative branch said the easiest way to make the transmitter systems "inert" — as set out in their recommendations — would be to take out their batteries.
Honeywell has made 6,000 of these transmitters and they're used in a wide range of planes. The actions announced by the FAA, however, apply only to 787s. FAA officials offered no explanation for why other operators of other planes with the same transmitters weren't included in the recommendation for inspections.
Freed reported from Minneapolis.
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