Boeing Begins 787 Test Flights

Boeing Co. began the first in a series of 787 Dreamliner test flights Monday, preparing for regulators to evaluate changes to its lithium-ion battery system and marking another step in the plane maker's effort to return the jet to commercial service.

The company flew what it dubbed a "functional check flight" on a production model 787 Dreamliner, painted in the colors of LOT Polish Airlines SA. Monday's flight at the company's Everett, Wash., factory was designed to check the systems of the jet, which hasn't flown since taking to the air for the first time on Jan. 13. The entire 787 fleet was ordered grounded by the regulators around the world on Jan. 16 after the lithium-ion batteries burned on two Japanese 787s earlier that month.

Following Monday's roughly two-hour flight, with six crew aboard, Boeing was to evaluate the performance of the aircraft's systems and move to perform ground tests for certification.

"The crew reports that the flight went according to plan," said Boeing spokesman Marc Birtel.

The LOT airplane is slated to fly next on a single demonstration test flight "in the coming days" for certification testing with the Federal Aviation Administration, said Mr. Birtel. FAA personnel are expected to participate in the airborne certification trial.

The flight is the first for a Dreamliner since Feb. 11, when Boeing conducted a pair of flight tests to gather temperature and operating data for the jet's original battery design.

The company has been conducting a series of ground and laboratory tests on the 787's new battery design, which includes increased spacing between the eight lithium-ion cells, a new stainless-steel containment casing, an updated battery charger and a venting system for any smoke or fumes, should a failure occur.

One critical ground test, which will be undertaken on one of Boeing's original 787 test aircraft, will see the battery pushed to destruction to verify the new containment and venting systems work as designed, said two people familiar with the tests.

Once Boeing receives final approval from the FAA and other global regulators, the company plans to deploy the modifications to the fifty 787 jets in operators' hands in "roughly the same order as deliveries," said Mr. Birtel, putting Japanese carriers All Nippon Airways Co. and Japan Airlines Co. at the front of the line of the eight current operators.