The US Department of Transportation sued Southwest Airlines and fined Frontier Airlines for flight delays, seeking civil penalties against Southwest and imposing a $650,000 fine on Frontier, part of a broader crackdown on airline delay issues.

Yesterday, the United States and U.S. Department of Transportation (DOT) disclosed a lawsuit against Southwest Airlines, accusing the airline of chronically delayed flights and interrupting passengers’ travels.

The DOT's moves come weeks after issuing a multi-million dollar fine against JetBlue.

The US Department of Transportation is flexing its muscles against airlines who operate chronically late flights.

The US Department of Transportation (DOT) has sued Southwest Airlines for allegedly operating numerous "chronically delayed" flights in violation of federal laws prohibiting deceptive practices.

Southwest is disappointed that DOT chose to file a lawsuit over two flights that occurred more than two years ago," a spokesperson for the airline said.

The Transportation Department continues its battle against chronically delayed flights with new actions against Southwest, featuring a Bay Area route.

The U.S. Transportation Department is suing Southwest Airlines and has fined Frontier Airlines over "chronically" delayed flights, disrupting passengers' travel and plans.

Key Takeaways Southwest Airlines stock fell Thursday after the Department of Transportation sued the airline over a pair of "chronically delayed flights."The federal agency says Southwest operated two flights in 2022 that arrived later than scheduled more than half the time for five consecutive months.

The Department of Transportation is suing the airline for what it characterized as months of "chronically delayed" flights — those that arrive at least 30 minutes late more than half the time.