After a series of almost comical if it wasn't so dangerous incidents earlier this year, all Boeing 787 aircraft were grounded, chiefly owing to a lithium-ion battery - only 42.3 centimeter (19-inch)-long, 25.9 centimeter (10.2-inch) in size - that feed's the jet's auxiliary power unit caught fire on a JAL (Japan Airlines) Boeing 787 Dreamliner jet at Boston’s Logan International Airport. As well, overheated battery led to an emergency landing of another 787 in Japan.
Afterwards, on January 16, 2013, Japanese airlines JAL and ANA (All Nippon Airways) who own many of the planes decided to ground their fleet, Boeing gave in and ordered a total grounding about a week later.
However, even though Boeing says it has NOT pinpointed the cause for the battery overheating, Boeing Co. chief project engineer Michael Sinnett says that a Boeing has a solution based on a new design for the lithium-ion battery system that has layers of safeguards to prevent overheating and measures to contain malfunctions.
About one-third of the plane is made by Japanese manufacturers, including GS Yuasa who supplied the troublesome lithium-ion battery, as well as the newly-designed one.
While one-third of the safety tests have already been completed, a Japanese official said it was possible flights could resume next month.
The 787 Dreamliner is the first airliner to make wide use of lithium-ion batteries. They are light and quick to charge but can suffer from “thermal runaway,” a chemical reaction in which a rise in temperature causes a spiral of temperature increases.Executives said it would take too long to figure out what had specifically caused the problems in Boston and southwestern Japan but the new design would ensure 787s are safe.
Boeing came up with 80 possible causes for the battery failures, categorized them into four groups, and came up with design changes such as better insulation between each battery cell so any malfunctions won’t spread. That was to allow the 787 to be back in the air more promptly, they said.
(Ed Note: Not a bad way to go about things, I suppose. basically, Boeing helped design a better battery. But, let's not forget - should any other company want to use the batter, they may want to follow Boeing's lead and ensure the current battery is a best-fit scenario for their needs.)
There were also changes to wiring for the battery, aimed at preventing overheating, and a new enclosure for the battery Boeing says would eliminate the risk of fire.
The enclosure has a direct vent to carry battery vapors outside the airplane, and small holes at the bottom of the battery case will allow moisture to drain from the battery, according to Boeing. The battery charger is also being adapted to beef up safety, it said.
While executives acknowledged that final approval would have to come from the FAA (Federal Aviation Administration), and didn’t rule out further delays to ensure safety, Boeing says it is in contact with the FAA and didn’t foresee any long delays.
"It’s a safe airplane. We have no concerns at all about that," Sinnett said.
Boeing executive vice-president Ray Conner offered his apologies to Japan for the problems.
"We do apologize for this situation," Conner says, adding that he was in Japan to meet with aviation authorities and airlines, and the company (Boeing) had picked Japan as the place to outline the battery fix.
Cheers,
Andrew Joseph
Photo above: AP/Elaine Thompson
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