More Bad News About 787 Dreamliner Batteries

A battery fire in a Japan Airlines Co. Dreamliner jet at Boston airport in January was not easily put out as mechanics and firefighters struggled with heavy smoke, an interim report by the U.S. National Transportation Safety Board said Thursday.

The NTSB said it has not drawn a conclusion on the cause of the battery fire or made recommendations in the interim report, citing ongoing investigations.

A mechanic "reported that he used a dry chemical extinguisher to try to put out the fire but that the smoke and flames did not stop," the report said.