The head of the pilots' union at Delta Air Lines is resigning.
Mike Donatelli said Wednesday that he will step down in September and union leaders will elect a new chairman.
Donatelli's decision comes less than two weeks after members of the Air Line Pilots Association rejected a Delta contract offer that union leaders had narrowly endorsed.
"It is time for the pilots of Delta Air Lines to unify," Donatelli said in a letter to the airline's 12,000 pilots.
The Delta offer, which lost by nearly a 2-to-1 margin, included pay raises but could have reduced profit-sharing under some circumstances. The union's executive council endorsed the deal 11-8. Delta promised to buy 60 new planes if the contract was ratified, but CEO Richard Anderson said last week that the order would be cancelled.
Atlanta-based Delta is the nation's third-biggest airline by traffic and just reported a record second-quarter adjusted profit of $1 billion. The pilots are Delta's only union work group.
Union leaders will meet Sept. 1-2 to elect a new chairman, said Donatelli, a Detroit-based Boeing 777 pilot who has flown for Delta since 1987. He was twice elected chairman, most recently for a two-year term that runs through 2016.
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