Boeing asks FAA to conduct 787 test flights

WASHINGTON U.S. regulators say they are evaluating a Boeing request to conduct test flights of its 787 Dreamliners, which were grounded nearly three weeks ago after a battery fire in one plane and smoke in another.

• Signs of runaway heat seen in 787 Dreamliner batteries
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• Japan sending Boeing 787 Dreamliner investigators to U.S.
• Japan's All Nippon Airways to seek damages from Boeing

"Boeing has submitted an application to conduct 787 test flights and it is currently under evaluation by the FAA," the airplane maker said. It declined to elaborate.

The Federal Aviation Administration confirmed the request, but officials there also declined to elaborate.

Boeing's request to the FAA was first reported by The Seattle Times.

A lithium ion battery in a Japan Airlines 787 caught fire on Jan. 7 while the plane was parked at Logan International Airport in Boston. Nine days later battery problems forced an emergency landing by an All Nippon Airways 787 in Japan.

CBS News correspondentSharyl Attkisson reported last week even more batteries had gone bad on the 787 Dreamliner since it began flying over a year ago. United Airlines had to replace multiple batteries on its fleet of six Dreamliners, and Japan's All Nippon Airways had 10 cases of battery replacement due to "technical issues" in 2012.

All 50 of the planes are grounded worldwide while investigations continue in the U.S. and Japan.