Delta Air Lines pilots voted against a proposed contract that their union leaders had said would make them the highest-paid in the industry, the union announced Friday.

The deal included an immediate 8 percent raise and three smaller hikes through 2018. But many pilots objected to a reduction in profit-sharing and work rule changes.

The rejection will send Atlanta-based Delta and its unit of the Air Line Pilots Association back to the bargaining table. The current contract runs through the end of this year, affording more time before pressures mount.

SEE HOW MUCH THE DEAL OFFERED PILOTS, BY AIRCRAFT TYPE

Delta has more than 12,000 pilots. Of those who cast ballots, 65 percent voted against the tentative labor agreement, while 35 percent voted in favor of it.

It’s unusual for the pilots to vote down a tentative agreement. Delta has had a relatively amicable relationship with its pilots union for years.

But the vote comes against the backdrop of Delta’s billions of dollars in profits and some pilots’ expectations of recouping what they lost during the company’s financial troubles and bankruptcy from 2005 to 2007.

“This contract fails to bring us to our work rules, pay and conditions from over a decade ago,” said Tim Caplinger, a Delta pilot who favors replacing ALPA with an independent union.

“Emotions often run high” in contract votes, union chairman Mike Donatelli acknowledged in a memo to members Friday. The union plans to hold a meeting later this month to determine the next step and reassess strategy.

The rejection of the agreement lessens the chance of an early deal that would enable Delta to give assurance to customers and shareholders.

“What you don’t want to have happen is for this to turn into a long, contentious-type negotiation,” said Barry Hirsch, professor of economics at Georgia State University’s Andrew Young School of Policy Studies.

Delta declined to comment.