The Transportation Department is suing Southwest Airlines, alleging the airline is violating federal regulations by operating chronically delayed flights due to unrealistic scheduling.
The lawsuit seeks maximum civil penalties.
The DOT found Southwest Airlines responsible for 180 disruptions on two routes between April and August 2022, with delays over 30 minutes in over 50% of flights for five consecutive months.
Federal rules require airlines to correct such schedules to avoid misleading consumers.
The department will likely file similar charges against Frontier Airlines after it determined that the airline had three chronically delayed flight routes between August 2022 and April 2023.
According to DOT, Frontier Airlines racked up at least 63 violations and may have to pay $650,000 in civil penalties.
JetBlue was recently fined $2 million for its own chronically delayed flights, with passengers getting a cut of the money.
Last year, President Joe Biden's administration unveiled a protection plan for air travelers that includes sweeping measures that aim to enhance transparency, protect customers and minimize refund-related hassles.
