Mechanics at Alaska Air have voted down a tentative contract agreement, reached in June, by a two-to-one margin, the Aircraft Mechanics Fraternal Association said on Wednesday.
The union said in a statement it would contact Alaska Air, whose pilots earlier this month also rejected a contract proposal, to renegotiate the proposal.
Alaska Air Chief Executive Bill Ayer, in a statement, said "while we were hoping for a different outcome, we will be heading back to the negotiating table... to seek a market-based contract that will allow Alaska Airlines to compete successfully and pursue growth, leading to good jobs and new opportunities for our employees."
Mechanics have been under pressure throughout the US as airlines seeking to cut costs to offset record fuel prices have increasingly sought to outsource aircraft maintenance.
