The Transportation Department is stepping up enforcement of persistent flight delays with a lawsuit against Southwest Airlines and a fine against Frontier Airlines. The agency said the U.S ...

(ABC 6 News) — The U.S. Department of Transportation says it is prepared to take airlines to court over flight delays. The agency has filed a lawsuit against Southwest, accusing the airline of illegally operating chronically delayed flights and disrupting passengers’ travel plans.

Spirit Airlines' executives remarked that they were still open to discussions if Frontier Airlines would improve its offer.

Frontier Airlines is attempting for a second time to merge with the now bankrupt Spirit Airlines, which declared bankruptcy late last year as budget airlines struggle.

Three U.S. senators said they want Frontier Airlines and Spirit Airlines to disclose whether they are manipulating seat fees by using customers' personal information to charge different fees to passengers on the same flight.

The Denver-based low-cost carrier said its combination with the Dania Beach, Florida-based Spirit would create a stronger low-cost carrier and benefit “from the very significant synergies Frontier expects to achieve by combining the airlines’ operations.”

Frontier Airlines is attempting for a second time to merge with the now bankrupt Spirit Airlines, which declared bankruptcy late last year as budget airlines struggle.

Secretary of Transportation Sean Duffy promised to improve the nation's transportation infrastructure and systems after Vice President JD Vance swore in Duffy on Wednesday afternoon.

The Appeals Court ruled that while the DOT had the power to issue such rules, the rulemaking process had some procedural gaps.

The Fifth Circuit Court of Appeals has remanded back to the U.S. Transportation Department a rule that would require airlines to disclose full fares, including all ancillary fees, when a flight search is conducted.

US Senate votes to confirm Trump nominee to head Transportation Department January 28 ... will tell a U.S. Senate committee that the United States has options to address the growing presence ...