DALLAS — A bankruptcy judge has temporarily blocked American Airlines from throwing out its contract with union pilots and imposing measures that would lower its labor costs.

Judge Sean Lane ruled in New York that American failed to prove that two parts of its proposal — dealing with furloughs and the outsourcing of flying to other airlines — were necessary to rebuild the company. But he said American could fix those elements of its plan and try again to throw out the contract.

That is exactly what American plans to do.

An American Airlines spokesman, Bruce Hicks, said the company would ‘‘adjust’’ the two provisions, make another offer to the pilots union, and by Friday file a new bid to cancel the union’s contract. The ruling came a week after the Allied Pilots Association rejected American’s final contract offer.

Keith Wilson, who was named interim union president when the previous leader was ousted after last week’s vote, said he was elated. He called the judge’s ruling ‘‘a rare Chapter 11 victory for labor’’ and ‘‘a significant setback for management.’’

Wilson said American went too far in using the bankruptcy process to eliminate union contracts, ‘‘and the judge recognized this in his decision today.’’