I don't think anyone should be especially reassured that no airframes have been lost due to battery fires. If any of the 787 battery fires that occurred on the ground had occurred in flight it isn't clear the aircraft would have survived.
If any of the 787 battery fires that occurred on the ground had occurred in flight it isn't clear the aircraft would have survived.
There was an in-flight fire, on an ANA 787. It made an emergency landing and the plane was evacuated. No lives were lost, and the airframe was not lost.
