Honeywell transmitter eyed in 787 fire probe: source

Investigators are looking at an emergency locator transmitter built by Honeywell International Inc as the possible cause of a fire on board a Boeing Co Dreamliner in London last week, according to a source familiar with the probe.

The transmitter, located in the upper rear part of the new airliner, uses a lithium manganese battery, said the source, who was not authorized to speak on the record. The fact that it is not powered by a lithium-ion battery could calm concerns about a re-occurrence of problems with batteries that grounded the entire 787 fleet for three months earlier this year.

Honeywell on Monday said it was participating in the investigation into a fire on a 787 operated by Ethiopian Airlines at Heathrow airport in London on Friday.

Honeywell said it was invited to participate in the probe, which is being led by Britain's Air Accidents Investigation Branch with help from the U.S. National Transportation Safety Board, the U.S. Federal Aviation Administration and Boeing.

Boeing declined to comment.

A spokesperson at the NTSB said the agency would not be providing an update since the investigation was being led by British authorities.

"Honeywell has been invited to participate in the Ethiopian Airlines Boeing 787 fire investigation by the UK's Air Accidents Investigation Branch," said Honeywell in a statement.

"We've sent technical experts to Heathrow to assist with the investigation; however at this time it is premature to speculate on the cause of the fire. We will continue to work closely with Boeing and the NTSB and await the analysis and output of the investigation before drawing any conclusions."

Boeing shares were trading 3.6 percent higher on Monday as concerns waned about another fleetwide grounding. News of the fire had sent Boeing's shares down 4.7 percent on Friday, knocking $3.8 billion off the company's market value.

Britain's Air Accidents Investigation Branch (AAIB) on Saturday said it found no evidence the fire was caused by the batteries that were implicated in the grounding earlier this year.

The planemaker resumed deliveries of the Dreamliner jet only in May, ending a period of nearly four months in which it was unable to provide new planes because of safety concerns about the battery system.

(Reporting by Andrea Shalal-Esa in Washington, Bijoy Koyitty in Bangalore, Alwyn Scott in New York and Nivedita Bhattacharjee in Chicago; Editing by Gerald E. McCormick and Tim Dobbyn)