CHICAGO -
Pilots at United Airlines say they could go on strike after two years of failed negotiations on a new contract at the airline formed through a combination with Continental.
The Air Line Pilots Association says 99 percent of voting pilots authorized a strike.
Federal law includes many obstacles to strikes among airline workers, and the vote doesn't mean pilots will be walking off the job anytime soon.
A United spokeswoman says the carrier expected a strike vote and said that is "not uncommon at this point in negotiations."
The National Mediation Board has not declared an impasse in negotiations, a necessary precursor to a legal strike. If the board, which has been mediating the negotiations, determines talks are deadlocked it could start a 30-day countdown toward a legal strike or lockout. The pilots' union has asked the board to take that step.
Even if the board cleared the way for a strike, Congress or the president could block it to prevent disruption in a key industry.
The pilots are unhappy over failure to win a single contract covering United and the former Continental airlines. The airlines combined in 2010 under parent United Continental Holdings.
Chicago-based United is the world's biggest airline by passenger miles.
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