Stuck on a plane: American, Delta fined for lengthy tarmac delays

American was fined $1 million, Delta $750,000 for exceeding the time limits on tarmac delays.

The U.S. Department of Transportation on Thursday fined American Airlines $1 million and Delta Air Lines $750,000 for lengthy tarmac delays over the past few years.

Airlines are required to allow passengers at U.S. airports to deplane after a plane has been sitting on the tarmac for three hours for domestic flights and four hours on international flights. The only exceptions to the time limit are for safety, security or air traffic control-related issues.

This is American's second major fine for tarmac delays. In 2016 it was fined $1.6 million, tying a record set by Southwest in 2015. There have only been two other fines over $1 million, levied against Frontier ($1.5 million) and United ($1.1 million,) according to DOT records.

In the current case, American exceeded tarmac delay limits on 13 flights between December 2015 and January 2017. Delta was cited for 11 flights between January 2017 and February 2018, with most due to a computer outage.

The longest tarmac delay on American: 5 hours and 35 minutes in Austin, Texas, in June 2016.

According to the DOT's consent order, an American flight from San Luis Potosi, Mexico, to Dallas diverted to Austin due to poor weather in Dallas. The DOT says American made a decision to "gas and go'' by refueling the aircraft and heading back to Dallas. The plane sat on the tarmac for 3 hours and 59 minutes before it began to prepare for takeoff but wasn't allowed to depart because a ground stop halted flights into Dallas. The flight was ultimately canceled but American didn't get the passengers off the plane within the four hour limit.

In its response to the DOT, American said each of the 13 flights in violation were diverted flights and that they were diverted for safety reasons, according to the consent order.

The airline said it is always mindful of the tarmac delay clock but "is also mindful of the need to get passengers to their destination airport instead of fully deplaning at the interim airport that is not anyone’s final destination.''

The bulk of Delta's tarmac delay troubles were tied to a computer outage in late January 2017 in Atlanta, which knocked out its gate management and flight dispatch systems for several hours, according to the DOT. Seven of the 11 flights in violation were flights arriving in Atlanta that night.

The DOT acknowledged the challenges of the computer outage but said it's Delta's responsibility to have a contingency plan and also to maintain its computer information systems.

In its response to the DOT, Delta noted that this is its first violation of the three-hour tarmac delay rules. It called the computer outage "extraordinary, unanticipated, and unpredictable'' and said it could not "reasonably have been anticipated.''

The airline said it gave passengers on the affected flights "substantial'' travel vouchers and frequent flier miles.

American and Delta will not pay their entire fines in cash to the DOT. American was credited $450,000 for compensation it paid to passengers on the affected flights and Delta was credited $450,000 for its passenger compensation and other expenses, including a backup data center.

This article originally appeared on USA TODAY: Stuck on a plane: American, Delta fined for lengthy tarmac delays