Southwest Airlines is being sued and Frontier Airlines fined over chronic flight delays by the Department of Transportation, the DOT announced Wednesday. Why it matters: Wednesday's announcement by the outgoing Biden administration's Transportation Secretary,

The Transportation Department is stepping up enforcement of persistent flight delays with a civil lawsuit against Southwest Airlines and a fine against Frontier Airlines.

The Department of Transportation on Wednesday sued Southwest Airlines, alleging the carrier operated chronically delayed flights, and fined Frontier Airlines for late-arriving flights.

The Department of Transportation sued Southwest Airlines Wednesday alleging it deceived customers by offering flights it knew it could not make on time.

DOT sues Southwest Airlines, accusing the airline of chronic flight delays while citing unrealistic scheduling that disrupted passengers.