The British Air Accidents Investigation Branch said in a statement that the fire resulted in smoke throughout the plane and extensive heat damage in the upper part of the rear fuselage. But it said that the damage was not near either of the plane’s lithium-ion batteries. And “at this stage, there is no evidence of a direct causal relationship” between the batteries and the fire, the statement said.
The investigation branch also said its initial inquiry would most likely take several days. It did not offer any other comment on possible causes.
The innovative planes had been grounded worldwide from January to April after two episodes involving fire or smoke coming from the new and more volatile types of batteries. But the planes began flying again in late April after regulators approved a series of fixes, including adding insulation between the battery cells and encasing the batteries inside a steel box.
The initial finding that there was no link to the batteries in the fire on the Ethiopian Airlines plane parked at Heathrow Airport on Friday would be a relief to Boeing, its investors and the 12 airlines that have bought the plane. But the outcome of the investigation could still be significant, depending on whether the investigators find problems with other systems.
Ethiopian Airlines said in a statement earlier on Saturday that it was continuing to fly its other 787s because the fire at Heathrow occurred after the jet had been on the ground for eight hours and “was not related to flight safety.” The airline did not comment on the possible cause of the fire.
Separately, The Financial Times quoted an Ethiopian manager in Britain as saying that maintenance workers had discovered a problem with the plane’s air-conditioning system during a routine inspection and had seen sparks but no flames. The report did not say when the inspection occurred, and aviation-safety officials in the United States were not sure what to make of it.
In addition to the British investigators leading the inquiry, a team from Boeing was on site along with representatives from the airline and from two American government agencies, the Federal Aviation Administration and the National Transportation Safety Board.
The fire caused no injuries or significant damage but did disrupt travel in Britain and elsewhere. Investors reacted nervously, sending Boeing’s shares down 4.7 percent on Friday.
Smoke came from the plane, named the Queen of Sheba, eight hours after it had been parked in a remote space at Heathrow and about four and a half hours before it was scheduled to depart for Ethiopia. No passengers were on the plane, which was connected to an external ground power source, according to people briefed on the episode.
It was also not clear if any maintenance was under way or how long the fire had been burning, though it was intense enough to burn through its carbon-composite skin on the top of the fuselage near the tail.
That area was not next to either of the plane’s new lithium-ion batteries, which caught fire or emitted smoke in the two earlier cases that led to the grounding of the first 50 787s. Unless they were charging, aviation experts said, the batteries would not have been in use if the plane were connected to ground power.
Safety investigators and Boeing did not comment on the possible cause of the fire.
Other experts said that some of the plane’s wiring, and the oxygen systems for passengers, would have passed through the damaged area, which was above the rear galley. It was also possible the fire migrated from another part of the plane, they said.
Richard L. Aboulafia, an aviation consultant at the Teal Group in Fairfax, Va., said the possibilities ranged from “something pretty benign,” like a lighted cigarette or a coffee machine left on, to a serious flaw in the plane’s new electrical system, which includes other innovative components besides the batteries. Or, he said, it could be something “not as easy or as terrible,” like a component that was installed incorrectly.
The Heathrow fire was not the only problem aboard a 787 on Friday. Thomson Airways, a charter airline, said that one of its Dreamliner planes traveling from Manchester Airport in England to Orlando-Sanford International Airport in Florida had to turn back “as a precautionary measure.”
Article source: http://www.nytimes.com/2013/07/14/business/fire-on-boeing-787-dreamliner-at-heathrow-in-london.html?partner=rss&emc=rss