Atlas Air Worldwide Holdings, Inc. announced yesterday that it has entered into a five-year agreement with FedEx Express to provide it with five 747-400 freighter aircraft for peak flying seasons beginning in 2017 and lasting through 2021.

Peak season flying generally occurs in the month of December and potentially earlier. An agreement to provide five aircraft for the 2016 peak season flying is already in place.

“We have worked closely and successfully with FedEx for many years, but this is our first agreement that allows both companies to plan for the longer term,” said William J. Flynn, Atlas Air’s president and chief executive officer. “We are excited to continue to serve FedEx and its customers.”

Atlas Air pilots, represented by the International Brotherhood of Teamsters, and its airline affiliate, Teamsters Local 1224, took a nearly unanimous vote authorizing a strike against the airline earlier this year.

The union claims that Atlas Air and its airline affiliates refuse to negotiate fairly with its Atlas, Polar Air, and Southern Air pilots. The Teamsters claim that Atlas is attempting to force the pilots to merge the now obsolete Atlas Air contract with Southern Air’s contract that was negotiated during bankruptcy.

Atlas Air Captain Mike Griffith, who has been active in a series of protests against Atlas Air and its affiliates, said he hopes this latest transaction serves as a wakeup call for Atlas executives.

“As our industry faces a major pilot shortage, Atlas pilots are asking themselves why they are doing the same job as FedEx pilots but for lower pay and longer hours that put their safety at risk,” Griffith added. “And more and more Atlas pilots are leaving for better opportunities. Atlas needs to get serious now about committing to a fair, industry standard pilot contract so our company can retain the experienced pilots we need to weather the shortage and deliver high-quality service to our clients.”