Spirit Airlines sues US government over flight slot allocations at Washington National

The DOT awarded five long-distance flight slots to American Airlines, Delta Air Lines, United Airlines, Southwest Airlines, and Alaska Airlines. Spirit and Frontier argue that these allocations have not been made according to set qualifications.

Spirit Airlines has filed a brief supporting Frontier's challenge against the DOT's decision on which carriers should receive these profitable slots. The brief alleges that "DOT misapplied statutory definitions in place for decades in an attempt to substantiate a pre-conceived decision over which carriers would receive slot exemptions under Section 502. "

The brief further claims that DOT reached its erroneous decision by creating a novel two-part test specifically designed to disqualify Frontier and Spirit based on incumbent definitions contrary to existing regulations. It also points out that Alaska Airlines should be disqualified from being considered a limited incumbent due to its extensive codeshare relationship with American Airlines.

Slot eligibility is governed by three classifications: new entrant, limited incumbent, and non-limited incumbent carrier. Four of the five routes were reserved for non-limited incumbents—airlines holding 40 or more slots at DCA— while one was for a limited incumbent. The contentious issue revolves around awarding Alaska Airlines the fifth slot as a limited incumbent when it codes about 100 American flights out of DCA.

Spirit and Frontier contend that law requires DOT to consider not just an airline's own slots but also those of its codeshare partners. In this case, they argue that Alaska's partnership with American technically gives it access to hundreds more slots than allowed under limited incumbent criteria.

As things stand now:

- United Airlines received approval for flights from DCA to San Francisco

- Southwest Airlines will operate flights from DCA to Las Vegas

- American Airlines secured routes from DCA to San Antonio

- Delta Air Lines was granted permission for flights from DCA-Seattle

- Alaska Airline won approval for service from San Diego-DCA

According Skift reports,"Alaska said it had 'intervened' in Frontier's lawsuit and that its flight out of Reagan National fulfills 'Congress's key objective connecting airports currently do not have nonstop service.'"