"Most likely, you're looking a manufacturing issue that will change as they learn to build the aircraft, but there's also the possibility that some systems might need tweaking," said Richard Aboulafia of the Teal Group in Fairfax, Va. "Either way, we're not looking at anything that undermines the aircraft's long-term prospects, just something that creates a large number of upfront headaches for Boeing and its customers."
Boeing has delivered 50 of the 787s, starting in late 2011, and has orders for nearly 800 more. To get through the backlog, Boeing is ramping up production to build 10 787s per month in Washington state and South Carolina by the end of the year. Boeing also said Friday it will open a third factory the Salt Lake City area to fabricate a tail piece for the plane.
By comparison, it builds more than one 737, Boeing's best-seller, every day.
The company said in November that it had begun making five 787s per month. But if any major manufacturing changes are needed to fix the problems, it could fall further behind in deliveries.
Carter Leake, an analyst who follows the industry for BB&T Capital Markets, said the broad review raises the chances that the FAA will find other things to scrutinize at Boeing. "You are more exposed than normal to something else being opened up," he said.
But he said Boeing is unlikely to slow down production, even if it ends up having to change the way part of the plane is built.
Huerta and LaHood rejected the notion that FAA may have not have been vigilant enough when it certified the 787 for commercial operations. LaHood noted that FAA technical experts logged some 200,000 hours on testing and reviewing the plane's design before it was certified in August 2011.
Boeing first applied to make the 787 in 2003. The first one flew in December 2009, and six test planes ran up some 4,645 flight hours. About a quarter of those hours were flown by FAA flight test crews, the agency said in 2011.
The battery that burned on Monday is used to start the plane's auxiliary power unit, a small engine in the back of the plane that acts as a generator to provide power on the ground, or if the jet engines quit. Other planes use hot air from the outside to start the APU. But one of the fuel-saving designs in the 787 was to get rid of the hot air system used by other planes, so its APU is started with electricity.
Lithium-ion batteries are potentially more susceptible to fire because, unlike other aircraft batteries, the liquid inside of them is flammable. The potential for fire increases if the battery is depleted too much or overcharged. Boeing has built in special circuitry and other safeguards designed to prevent that situation.
The review also raises questions about the 787's ability to win approval to fly extremely long distances away from airports. That's a big issue, since the 787's long range is one of its main selling points. Regulators want to know that long-range planes are safe to fly even if the nearest airport is more than an hour away. Such certification is important for flights across the Pacific.
The 787 already has approval for flights up to three hours away from the nearest airport. It has met the flight test requirements to go up to 5.5 hours away but doesn't have permission yet because of a rule change by the FAA, said 787 chief engineer Mike Sinnett on Wednesday.
Boeing's 777 won such approval in December 2011.
Freed reported from Minneapolis. Associated Press writers Scott Mayerowitz in New York, Manuel Valdes in Seattle and Paul Foy in Salt Lake City contributed.
Follow Joan Lowy at http:www.twitter.com//AP_Joan_Lowy