The US Federal Aviation Administration (FAA) has dropped a probe into gate assignments for Delta Air Lines (DL, Atlanta Hartsfield Jackson) at the Dallas Love Field airport as a part of undisclosed settlement agreement, Air Transport World has reported.

The regulator opened the investigation in 2015 after the city authorities asked the FAA for assistance and intervention in the ongoing spat between Delta Air Lines and Southwest Airlines regarding gate allocation at the Dallas Love Field airport.

Out of Dallas Love Field's 20 gates, 16 are used exclusively by Southwest Airlines under the terms of a 2013 agreement with the city authorities. The LCC is under an obligation to forego one gate at Love Field for every gate used at Dallas/Fort Worth, which it currently does not serve.

Since 2015, Southwest Airlines has also been leasing two more gates at Love Field from United Airlines, which does not fly to the airport. The remaining two gates are used by Alaska Airlines since its acquisition of their previous operator, Virgin America.

Delta has been arguing that the 2015 agreement between United and Southwest violated fair access rules and should have been reviewed more closely by the city authorities. Despite the termination of the FAA investigation, which can be seen as an argument in favour of the current allocation of gates at Love Field, the carriers are still entagled in legal proceedings and are scheduled to go to court in February 2019.

According to the ch-aviation capacity module, Southwest Airlines currently operates 1,220 weekly departures out of Love Field, 87.9% of all. Alaska Airlines and Virgin America operate a total of 120 weekly departures between them, while Delta, which continues to use one of the two gates subject to the 2015 United/Southwest agreement, operates 33 weekly departures out of the airport.

The city's main airport at Dallas/Fort Worth is a hub for American Airlines, which operates 5,041 weekly departures out of the facility. Delta Air Lines is the second-largest carrier at the airport, albeit much smaller with just 291 weekly departures.