fault caused an emergency landing by a United Airlines plane on Dec. 4, the same day that the FAA ordered inspections of fuel lines because of leaks..
A few weeks later, a 787 in Boston spilled about 40 gallons of fuel on the tarmac as it taxied for take-off. Then a plane in Japan had fuel leaks. Another had brake problems and a third had a cracked cockpit windscreen.
Such events are usually considered ordinary, but coming in quick succession, they cast a pall over the Dreamliner.