Spirit Airlines (NK, Fort Lauderdale International) has reportedly filed a lawsuit against the United States Department of Transportation (DOT) after the agency decided to withhold peak-period slots at New York Newark that previously belonged to Southwest Airlines (WN, Dallas Love Field).

Southwest announced on July 25 that it would cease operations at the airport by November 3, and the Federal Aviation Administration (FAA) has since received requests from a number of carriers, including Spirit, seeking approval for new operations to replace those dropped by Southwest, according to Air Transport World.

The DOT opted on October 2 not to reallocate the 16 landing and takeoff rights for summer 2020, citing congestion at the airport during peak periods, deciding instead to study the effects of fewer operations on summertime traffic there.

Spirit branded the decision “arbitrary and capricious, an abuse of discretion, and otherwise not in accordance with law,” in a suit it filed with the US District Court of Appeals for the District of Columbia on November 25, asking the court to review the move.

“The Department of Transportation’s decision to retire the landing rights previously operated by Southwest Airlines will mean that United Airlines holds nearly 80% of the authorisations at one of the busiest airports in the country and would operate more than 90 monopoly routes,” the ULCC's spokesman Erik Hofmeyer said in a statement.

The appeals court has set a deadline of January 2 for motions and first replies in the case.

The DOT changed Newark from a slot-controlled to a schedule-facilitated airport in 2017, allowing it to cap takeoffs and landings during peak hours at 79 per hour. Southwest acquired its 16 daily rights at Newark when United and Continental Airlines merged in 2010 as the two carriers gave up slots to allow new competition into the airport.