Boeing 787 probe looks at bad battery batch theory

U.S. officials and Boeing Co. are investigating whether defective lithium-ion batteries from the same batch caused incidents in two 787 Dreamliners that triggered the plane's worldwide grounding, according to two people familiar with the incidents.

If that proves to be true, it could show a flaw causing the incidents was confined to a small number of 787s, rather than a systemic fault with the plane's engineering, design or manufacturing and could speed the resumption of flights. The information is preliminary and investigators haven't yet ruled out other causes.

The Federal Aviation Administration, which certified the plane in 2011, ordered flights on the 787 halted until airlines can show the plane's batteries "are safe and in compliance."

The FAA's move, its first in 34 years to ground an entire plane model, set off a race to find and fix whatever caused the battery-fault warning on a 787 operated by All Nippon Airways Co. and a fire on a Japan Airlines Co. jet.

"Nobody knows what the fix is because they don't know what the problem is," said John Goglia, a former member of the U.S. National Transportation Safety Board.

The batteries were made by Japan-based GS Yuasa Corp. Marc Birtel, a spokesman for Boeing, said he couldn't comment on the investigation.

A flaw in a battery, such as a manufacturing defect that allowed the flammable liquid inside to leak, might trigger a fire in one battery cell that would then ignite other cells within the pack, according to tests on generic batteries conducted by the FAA.

The 787 is the first airliner to make extensive use of lithium-ion batteries to help power its electrical systems. The batteries charge faster and can be better molded to space-saving shapes compared with other airplane batteries. With AP