Japan aviation officials call on Boeing to further improve 787 batteries
Published 2:20 pm Wednesday, December 31, 2014
In a report released earlier this month, Japanese civil air authorities say that Boeing 787 Dreamliners can continue flying even after a single battery failure, but nonetheless, are pressing the airplane maker to redesign the lithium ion batteries, according to news reports.
The Dec. 19 report by the Japan Civil Aviation Bureau wrapped up its investigation into overheating in a battery on a Japan Airlines 787-8 that was parked. The fire occurred Jan. 14, 2014.
JCAB recommends in the report that Dreamliner operators should “adopt the design changes which will be prepared by Boeing and implement them as soon as possible,” reports Stephen Trimble at Flightglobal.
The airplane’s lithium ion batteries have caused dangerously high temperatures on three occasions in the past two years — two incidents in early 2013 and the third in early 2014.
After the first two events, Dreamliners around the world were effectively grounded around the world.
The events were caused by short-circuiting, but despite multiple investigations, no one has determined the exact cause of the overheating incidents.
The lithium ion batteries on Boeing’s 787 Dreamliner are much more powerful and much lighter than batteries used on older airplanes.
By spring of 2013, Boeing engineers came up with a redesigned housing to contain and mitigate an overheating battery.
That fix worked in the most recent incident, in which damage was almost entirely limited to a single battery cell in the airplane’s forward electrical/electronics bay, according to the report.
JCAB’s findings are “a key litmus test for validating the battery modification Boeing has put in place,” writes Daniel Tsang, an aerospace analyst with Aspire Aviation.
Nonetheless, JCAB calls for further improvements by Boeing, Trimble reports.
Boeing’s fix contained the damage, he writes. “But the third cell venting incident showed that the first layer of protection — preventing a cell from overheating in the first place — failed, the JCAB report says.”
Concerns about fires caused by lithium-ion batteries prompted the International Civil Aviation Organization to recommend this year that countries ban the batteries from being shipped as air cargo.
Dan Catchpole: 425-339-3454; dcatchpole@heraldnet.com; Twitter: @dcatchpole.
