The certification plan is the first step toward returning the 787 to service, and will require extensive testing and analysis.
“This comprehensive series of tests will show us whether the proposed battery improvements will work as designed,” said Transportation Secretary Ray LaHood.
Battery maker GS Yuasa Corporation believes the fix for the battery should include a voltage regulator that could stop electricity from entering the battery, the Wall Street Journal reported, citing government and industry officials.
Boeing proposed its fix to the US Federal Aviation Authority on Friday.
But on Thursday, Yuasa told the agency that its laboratory tests indicated a power surge outside the battery, or other external problem, started the failures on two batteries, according to the newspaper.
The FAA confirmed the meeting with Yuasa, but did not give any details. A Yuasa spokesman declined to comment.
A Boeing spokesman said that the investigation has not showed that overcharging was a factor and that the 787 had quadruple-redundant protection against overcharging in any case.
“Our proposal includes multiple layers of protection covering the known potential probable causes of the events,” he said.
He added that Boeing was co-ordinating with key suppliers.
The aircraft manufacturer proposed ways to fix the 787’s battery problems which have led to its grounding at a meeting with the FAA on Friday.
Boeing is reported to believe the measures could have the aircraft flying by late March or April.
However, the cause of overheating in a lithium-ion battery on a Japan Airlines 787 has yet to be identified.
The 50 Dreamliners in service around the world have been grounded since January 16 after a battery fire on the Japan Airlines 787 parked at Boston and an emergency landing by an All Nippon Airways aircraft in Japan.
Investigators believe a short circuit in one of the battery cells caused overheating that led to the fire which then spread through the battery.
Boeing has proposed insulating the battery’s lithium-ion cells from one another to prevent fire spreading, encasing the battery in a fire-proof shell and installing sensors.
It also proposes a venting mechanism to remove fumes which led to the emergency landing.
Japanese investigators have identified the likely cause of the fumes which led to the emergency landing, reporting they found faulty wiring on the battery of the All Nippon Airways 787.
The aircraft’s auxiliary power unit was incorrectly connected to the main battery. However, the root cause of the battery fire in Boston has not been found.
Japanese transport minister Akihiro Ohta said: “It’s too early to say we are over the hump.”
Aviation analyst Douglas McNeill told the BBC: “Until it’s crystal clear what went wrong the FAA will be reluctant to let the 787s resume [flying].”
US transport secretary Ray LaHood has warned the 787 will not fly again until the FAA is “1,000% sure” the batteries are safe.
Meanwhile, All Nippon Airways is cancelling all Boeing 787 Dreamliner flights until at least the end of May.
More than 1,700 flights in April and May are affected, a period that includes Japan’s Golden Week holiday. This takes the total number of affected ANA Dreamliner flights to 3,600.
An ANA spokeswoman told the BBC: “Unfortunately, it includes Golden Week, but we have decided to inform our customers in advance as the prospect for their resumption is still unseen.”
ANA is Boeing’s biggest Dreamliner customer, with 17 of the world’s 50 operational 787s.all of which have been grounded. International regulators grounded all Dreamliners last month in so that safety checks could be carried out on their lithium ion batteries.
Wetravel2u's Weblog 