ATLANTA — Two major flight carriers are being slapped with steep fines for apparently violating federal rules on long tarmac delays. 

According to the U.S. Department of Transportation, Delta Air Lines and American Airlines are being fined $750,000 and $1 million each, respectively, after an investigation found multiple examples of flights being held on the tarmac for too long, going back to 2015.

Under DOT rules, airlines operating aircraft with 30 or more passengers are not allowed to have domestic flights to idle on the tarmac for more than three hours - four hours for international flights - without giving passengers a chance to leave the plane. The only exceptions are for safety, security or traffic control-related issues. 

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Federal investigators found that 10 domestic and three international American Airline flights violated wait times between December 2015 and January 2017. Meanwhile, the DOT found 11 domestic Delta flights violated the rule between January 2017 and February 2018.

Both the airlines will be credited for any compensation provided to passengers affected by the delayed flights - American will get $450,000 of its $1 million fine and Delta will get $450,000 of its $750,000 fine. 

In a statement to 11Alive, American blamed some of those delays on "exceptional weather events" but said it takes its responsibility to comply with DOT rules "seriously." 

"The safety and well-being of those who choose to fly with us is always our top priority, and we regret any inconvenience caused to our customers whose travel plans were disrupted," the airlines said in the statement. "We apologized to those who were impacted by these tarmac delays and have put procedures in place to help better accommodate our customers when inclement weather occurs."

11Alive also reached out to Delta for a statement, but we have not heard back from them yet.

If passengers want to file a complaint for their flight, they can do so with the DOT here

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