United faces biggest fine yet for ground delays

United Continental Holdings Inc. was fined $1.1 million by U.S. regulators for stranding passengers at Chicago’s O’Hare International Airport last July, the largest penalty since rules went into effect in 2010.

Thirteen United planes were delayed on the ground for more than the three-hour limit during thunderstorms on July 13, 2012, the U.S. Department of Transportation said Friday. Airlines must return to a gate to give passengers a chance to exit aircraft that have been stranded on a tarmac longer than three hours.

United didn’t use its contingency plan to deal with long delays on the ground, and the plan was inadequate to handle the situation, the DOT said. The carrier also didn’t contact airport officials or other carriers for assistance, according to the release.

“It is unacceptable for passengers to be stranded in planes on the tarmac for hours on end,” Transportation Secretary Anthony Foxx said in the release.

In at least two aircraft, the carrier failed to provide functioning restrooms during the delays, according to a consent order issued today.

The planes included United’s own and those of a partner flying under the United Express name, according to the DOT.

“We are committed to complying with the tarmac delay regulations and we continue to improve our procedures while maintaining the safety of our customers and coworkers,” Mary Ryan, a United spokeswoman, said in an e-mail.

Severe thunderstorms with lightning hit O’Hare on July 13, 2012, shutting portions of the airport grounds and cutting off access to United’s gates. Because of multiple flight delays, there were more planes on the ground than gates, according to DOT.

Because of the closings, the airline had “no viable options to deplane passengers without risking the safety of both the passengers and ground staff,” Ryan said.

Of the $1.1 million, United must pay the government $475,000. The airline was credited with $185,000 in compensation it made to passengers on the flights. The DOT is allowing the carrier to spend $440,000 of the penalty to purchase a system to track planes on the ground at O’Hare, according to the consent order.