The head of National Transportation Safety Board said today that the FAA should reconsider their approval of the Dreamliner's lithium-ion battery.
The New York Times explains that Boeing said the batteries on the new 787 planes "were likely to emit smoke less than once in every 10 million flight hours."
Once the planes started flying, however, "smoke came out of the batteries twice last month in fewer than 100,000 hours of commercial flights."
Not only that, reports the AP, but Boeing also said that any short circuit within the battery would be contained to a single cell. The NTSB found that in the case of the Japan Airlines 787 that caught fire in Boston, the "the fire started with multiple short-circuits in one of the battery's eight cells." That spread to the other seven cells and created an "uncontrolled chemical reaction known as 'thermal runaway.'"
"This investigation has demonstrated that a short-circuit in a single cell can propagate to adjacent cells and result in smoke and fire," Hersman said. "The assumptions used to certify the battery must be reconsidered."
Because of the battery issue, the 50 Dreamliners in service around world have been grounded since mid-January, causing a major headache for Boeing.
"Hersman said a review is needed of the 'special conditions' under which aviation regulators approved Boeing's use of this particular battery technology on the 787, a decision that has lately come under close scrutiny.
"The NTSB plans to issue an interim factual report in 30 days, though the decision on returning the plane to regular flight rests with the Federal Aviation Administration."