Boeing Co said on Thursday that it has completed work to address a structural problem on its delayed 787 Dreamliner, and still expects the airplane's maiden flight to take place before year's end.

The company said reinforcements have been installed within the side-of-body section on the first 787. New fittings at 34 stringer locations were installed within the joint where the wing is attached to the fuselage.

The company said completing the modifications was a crucial step toward the first flight of the Dreamliner.

In late June, the No 2 plane maker behind EADS unit Airbus, put off the first flight of the Dreamliner, citing the structural problem. It was the latest in a series of delays that have put the test flight two years behind its original schedule.