Boeing will redesign battery system and conduct new tests , says it is confident . Analyst : Tests will need to be lengthy and thorough . May still take months before commercial Dreamliner flights resume . Comment:
Boeing will redesign battery system and conduct new tests , says it is confident . Analyst : Tests will need to be lengthy and thorough . May still take months before commercial Dreamliner flights resume . Boeing 's 787 was grounded in January after two battery fires .