UPS mechanics have rejected a new contract proposal, pushing company and union leaders back to the negotiating table at which they’ve been sitting for five years.

Tim Boyle, president of Teamsters Local 2727, declined to comment, but a company spokesman told Insider Louisville via email that the logistics giant is “disappointed.”

UPS spokesman Mike Mangeot said that the parties had negotiated “a generous agreement that maintained industry-leading wages and benefits and provided excellent income security for our aircraft mechanics.”

Courtesy of the Teamsters

Negotiations, which had begun in October 2013, affect about 1,300 employees, including about 550 in Louisville, and play a pivotal role in the operations of one of the company’s North American hubs, where it employs about 21,000. The mechanics inspect the planes to make sure that they take off and land safely.

The parties announced in August that they had reached a tentative agreement that included an immediate 16 percent pay raise and a 30.7 percent pay raise by the end of the contract.

Negotiations had dragged on because they are governed by the Railway Labor Act, a federal law that makes it more difficult for the parties to initiate a strike or lockout. Any such action has to be approved by the National Mediation Board.

Union leaders and members had told Insider early this year that the major sticking points in negotiations included proposed changes to health benefits for current employees and retirees. The company had said that it pays industry-leading wages and has made generous offers that include options such as premium-free health care.

Before the union and the company had reached the tentative deal, a Louisville-based mechanic had told Insider that the prolonged negotiations were wearing him out.

Boyle declined to comment on Tuesday afternoon and did not want to provide details about the vote.

Mangeot said that the company would meet with Teamsters leaders and the NMB “in the near future to discuss the next steps.”

He said there would be no impact on operations.