The airline was ordered to cease and desist from future violations of the tarmac-delay rule, the Transportation Department said Friday in a release.
"It is unacceptable for passengers to be stranded in planes on the tarmac for hours on end," Transportation Secretary Anthony Foxx said. "We will continue to require airlines to adopt workable plans to protect passengers from lengthy tarmac delays and carry out these plans when necessary."
United was fined for 13 lengthy tarmac delays that took place July 13, 2012, when severe thunderstorms and lightning caused several ramp closures and disrupted air traffic at O'Hare. Delays by United and its United Express affiliates exceeded the 3-hour limit for tarmac delays by as little as 2 minutes and as much as 77 minutes.
Although United had a contingency plan for tarmac delays, the department's Aviation Enforcement Office said it found the airline did not implement the plan during the delays, and the plan was inadequate to cover foreseeable weather emergencies in which there were more planes on the ground than space at gates.
The enforcement office found United did not contact airport personnel or other airlines for help during the delays and that bathrooms aboard two United Express flights were inoperable during part of the delays.
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