Boeing has completed the first test flight of a 787 Dreamliner equipped with a redesigned battery system, which is an important step towards certification from federal safety officials.
The LOT Polish Airlines 787 departed Paine Field in Everett, Wash., at 12:11 PST Monday and landed safely back at Paine Field at 2:20 p.m.
The flight, which lasted 2 hours and 9 minutes, "went according to plan," Boeing said in a statement.
Spokesperson Marc Birtel said Boeing will analyze data from the test and prepare to seek certification "in the coming days."
The 787 Dreamliner has been grounded worldwide since mid-January after a fire broke out on a parked 787 in Boston and a smoldering battery forced an emergency landing on another 787.
Boeing does not know the root cause of the malfunction, but the company unveiled a proposed fix on March 15.
The change makes it "very unlikely" that another battery event will happen, said Ron Hinderberger, Boeing's vice president for 787-8 engineering.
Boeing hopes the battery's redesigned steel box won't just contain a battery fire, but will prevent one from starting by choking off the flow of oxygen and venting the battery gases and air inside the box outside of the plane.
The new design was tested before Boeing proposed it to the FAA. It will be retested so it can be certified for use on the plane, Hinderberger said.
After that, approval will be up to the FAA.
He said it would be inappropriate to speculate on how long that would take.
The Associated Press contributed to this report.