A top Boeing executive plans to meet with the head of the Federal Aviation Administration on Friday to propose fixes for the battery problems that have grounded its innovative 787 jets, industry and government officials said Wednesday.
They said the company feels confident that it has narrowed down the possible ways that the new lithium-ion batteries could fail, increasing the chances that a handful of changes might provide enough assurance that the batteries would be safe to use.
The F.A.A.’s top official, Michael Huerta, is not expected to approve the changes on Friday when he is scheduled to meet with Ray Conner, the president of Boeing’s commercial airplane division. But the meeting could start a high-level discussion and provide Boeing with early guidance on the mix of changes that would be needed to get the planes back in the air.
The government and industry officials agreed that Boeing will ultimately have to redesign at least part of the batteries to eliminate the risk that a short-circuit or fire in one of the eight cells inside could spread to the others, as investigators have said occurred on a battery that caught fire at a Boston airport on Jan. 7.
One important question is how far Boeing will have to go in making the changes before the F.A.A. will let airlines resume flights with the 50 jets that have already been delivered.
The officials said Boeing might have to take some immediate steps to insulate the cells from one another and then make greater changes over time to further eliminate possible ways that the batteries could fail.
Boeing, based in Chicago, would also have to wall off the battery within a sturdier metal container, add systems to monitor the activity inside each cell and create channels to vent any hazardous materials outside the plane.
Until now, most of the public statements by regulators have focused on the need to pin down the cause of the battery problems. But investigators, now weeks into their work, have been able to find only limited clues in the charred remains of the two batteries.
As a result, government and outside experts, working closely with Boeing engineers, have been studying the recent problems and research on lithium-ion batteries carried out since Boeing won approval for its batteries in 2007 and, in essence, trying to come up with a safer design.
Aviation experts said the examination of such changes reflected what could end up being a difficult calculation for safety regulators: Will there be a way to ensure the safety of the batteries if they cannot tell for certain what set off the problems on the two planes?
The F.A.A. and other regulators around the world grounded the new fuel-efficient planes after another one of the jets made an emergency landing in Japan on Jan. 16 with smoke in the battery compartment.
The lithium-ion batteries weigh less but provide more energy than conventional batteries, and the 787s make greater use of them than other planes. The stakes are substantial for Boeing, which will have to pay penalties to some of the airlines that have been unable to use them. Boeing also cannot deliver more of the planes while they are grounded.
The company has orders for 800 additional planes, which are expected to usher in a new era in aviation. The jets rely as well on lightweight carbon composites and new engines to cut fuel consumption by 20 percent.
Federal and industry officials said Boeing would probably have to spread the eight cells in the batteries farther apart — or increase the insulation between them — to keep a failure in one cell from cascading to the others in the “thermal runaway” that led to the smoke and fire.
Battery experts are also looking into whether vibrations in flight could have added to the risks of unwanted contact between the cells.
But it is not clear how long it will take to make each of these changes and test them to the satisfaction of regulators. So engineers for the F.A.A and Boeing have been discussing which changes would have to be made immediately and which ones could be added later.
Government and industry officials that it was still too early to know if Boeing’s current plans would satisfy regulators and the flying public.
Boeing to Propose Battery Fixes to F.A.A.
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Boeing to Propose Battery Fixes to F.A.A.
