"All new aircraft types have issues, and the 787 is no different. We continue to have confidence in the aircraft and in Boeing's ability to fix the issues, just as they have done on every new aircraft they have produced," Smisek said. United is working closely with Boeing and the FAA to return the plane to service, he said.
The 787 is the world's first airliner made mostly from lightweight composite materials. It also relies on electronic systems rather than hydraulic or mechanical systems to a greater degree than any other airliner. And it is the first airliner to make extensive use of lithium ion batteries, which are lighter, can hold more energy and are easier to fit into odd-shaped spaces in airplanes than other types of batteries.
The FAA certified the 787 battery system even though lithium ion batteries are more susceptible to catching fire when they overheat or short-circuit than other types of batteries.
Securaplane, an Arizona company that won a contract to design a battery charger unit for the Boeing 787, had a fire in November 2006 that ignited when the battery used by an engineering technician exploded during testing, destroying the firm's labs and production building, according to a summary of findings prepared by an administrative law judge who heard a whistleblower complaint filed by the technician. The technician went to court after he was fired.
Michael Leon, the technician, said he complained to his employer that the battery was damaged and unsafe and that there were discrepancies between the schematics and assembly documents used in building the battery charger. Administrative Law Judge William Dorsey, who heard Leon's complaint at trial, said in his ruling that one possible cause of the fire was Leon's misuse of the battery during testing.
The FAA investigated Leon's complaints in 2008 and 2009, the agency said in a statement. "The investigation determined that the battery charging units in the complaints were prototypes, and none are installed in Boeing 787 aircraft," the statement said. "Securaplane's production of a particular printed circuit board complied with FAA requirements."
Associated Press writers Joshua Freed in Minneapolis and Jacques Billeaud in Phoenix, Ariz., contributed to this report.
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