Battery smokes on JAL 787; Boeing fix appears to work
The incident on a 787 in Tokyo appears to have been limited by the containment-box protection system Boeing engineers designed to ensure the plane’s safety if the battery malfunctioned.
Seattle Times aerospace reporter
Almost exactly a year after a smoking lithium-ion battery on a Japan Airlines (JAL) 787 Dreamliner grounded the jet for more than three months, the same airline reported a smoking battery in a parked 787 on Tuesday.
However, the incident appears to have been limited by the containment-box protection system Boeing engineers designed to ensure the safety of the plane in case of a battery malfunction.
JAL reported the 787 was on the ground at Tokyo’s Narita airport preparing for departure to Bangkok, with no passengers on board. A maintenance technician “in the cockpit found that the white smoke was wafting outside of the window and that the message which indicated the possibility of main battery system failure was displayed on the cockpit display,” the airline said.
“The inspection of the battery case inside the battery enclosure revealed that the safety pressure relief valve ... of one cell of the eight cells opened,” JAL said. The relief valve is supposed to open if pressure rises inside a cell,
When the one valve opened, it dispersed liquid inside the plane’s main battery container, JAL said.
After the problem was discovered, the airline substituted another 787 and the flight departed almost on time.
Boeing spokesman Doug Alder said, “We are aware of the 787 issue that occurred Tuesday afternoon at Narita, which appears to have involved the venting of a single battery cell.”
“The improvements made to the 787 battery system last year appear to have worked as designed,” he added. “We sincerely regret any impact caused to Japan Airlines and are working with them to return this airplane to service.”
The cause is under investigation, and JAL will share details with Japan’s transportation ministry and Boeing, said Seiji Takaramoto, a spokesman for the Tokyo-based carrier.
Lithium-ion batteries on Dreamliners failed twice in early 2013, first on Jan. 7 on a JAL plane parked at Boston’s Logan airport and then on Jan. 16 aboard an All Nippon Airways jet in flight in Japan.
That spurred regulators to order the planes parked worldwide while Boeing crafted a fix.
Boeing’s solution was to encase each of the 787’s two main lithium-ion batteries in a hefty steel box with titanium venting tubes that would carry any smoke, flames or flammable vapors outside the airplane.
The Federal Aviation Administration cleared the way for Dreamliner flights to resume more than three months later.
The National Transportation Safety Board (NTSB) is still investigating the cause of the 787 fire in Boston. The safety agency said recently it expects to finish by the end of March and present findings at a public meeting this fall.
NTSB spokesman Peter Knudson said Tuesday that “anything we can learn about the (latest) battery failure would be helpful” to the ongoing investigation.
Boeing stock slipped on Tuesday’s news, closing down 69 cents, or 0.5 percent, at $140.01.
This report includes information from Bloomberg News and The Associated Press.
Dominic Gates: (206) 464-2963 or email@example.com