Bart Jansen

USA TODAY

WASHINGTON – American Airlines was fined $1.6 million for leaving dozens of planes on tarmacs for more than three hours without allowing passengers to leave, the Transportation Department announced Wednesday.

The infractions involved flights from 2013 to 2015, according to the department’s Aviation Enforcement Office investigation. The incidents included 20 flights at Charlotte on Feb. 16, 2013; six flights at Dallas/Fort Worth on Feb. 27, 2015; and one flight at Shreveport, La., on Oct. 22, 2015.

The Charlotte delays during a snowstorm involved flights of American, predecessor US Airways and regional affiliates PSA Airlines, Piedmont Airlines, Air Wisconsin Airlines, Mesa Air and Chautauqua Airlines. The flights involved a total of 860 passengers.

The department ruled that the carriers failed to anticipate the situation in time to prevent the long delays, which at its peak involved 80 delayed flights at the hub, despite a warning from the National Weather Service that an inch or two of heavy snow would fall each hour.

The Dallas/Fort Worth delays occurred during heavy snow and rain and came on a day when American cancelled more than 400 flights at the hub. But the department ruled that American failed to take appropriate measures to prevent the delays, as American and Envoy flights were delayed waiting in congested de-icing lines during the storm.

The fleet and hubs of American Airlines, by the numbers

The investigation at Shreveport found the delay was at least partially due to mismanagement of personnel and resources, according to the department. The flight with 131 passengers was one of 13 diverted from Dallas because of thunderstorms, but passengers were kept on the flight 3 hours and 37 minutes.

“Our tarmac rule is meant to prevent passengers from being trapped in aircraft on the ground for hours on end,” Transportation Secretary Anthony Foxx said. “We will continue to take enforcement action as necessary to ensure passengers are not kept delayed on the tarmac for lengthy periods of time.”

American replied that it takes its responsibility to comply with the rule seriously, and cooperated fully with the investigations.

In Charlotte (CLT), the airline said it was trying to get connecting passengers to their final destinations for a holiday weekend when 200 other flights were canceled and 200 were delayed less than three hours. The airline said diverting flights to other regional airports amid uncertain weather forecasts would have been a mistake that would have created gridlock as crews' shifts ended, which would have stranded passengers at small airports.

"It is the opinion of American that US Airways' decision to bring aircraft into CLT was the best result possible in this unexpected and difficult situation, as evidenced by the fact that all affected passengers were en route to their final destinations before noon the next day," the airline said in a statement.

In Dallas, the airline said weather forecasts were unclear, with a little dry snow forecast rather than the heavy, wet snow that arrived longer than predicted. Some unexpected problems arose, too, including a de-icing truck breaking down and blocking planes from moving.

In Shreveport, the airline said only one of 13 diversions was delayed more than three hours. A single airport bus was available to deplane passengers, the airline said. And a different flight had a passenger with a medical issue, which took priority for unloading, the airline said.

DOT fines Southwest $1.6 million for Midway tarmac delays

The penalty matched a $1.6 million fine assessed against Southwest Airlines in 2015.

American will be credited for $602,000 in compensation provided to passengers on the flights and $303,000 for acquiring, operating and maintaining equipment to monitor conditions at Charlotte and Dallas. The remaining $695,000 must be paid within 30 days, the department said.

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