The leaders of Northwest Airlines’ pilots union...

The leaders of Northwest Airlines’ pilots union called for a strike against the carrier beginning Saturday, the Air Line Pilots Assn. said. The union’s 4,900 pilots will vote this week on whether to support the strike, and results are expected Friday, a union spokesman said. The leaders called for the strike after contract negotiations with Northwest broke down. The St. Paul, Minn.-based airline is asking for wage, benefit and work-rule concessions, the union spokesman said. He added that the pilots do not plan to ask for federal mediation in the dispute.