Amid severe thunderstorms on July 13, 2012, the carrier left passengers at Chicago's O'Hare Airport in 13
According to the DOT, the planes exceeded by three-hour limit by as little as two minutes and as much as 77 minutes.
The DOT's Aviation Enforcement Office found that United did not implement is contingency plan for tarmac delays, and that its plan was inadequate in any case. United did not contact airport personnel or other airlines for help, and the bathrooms on two of the planes were inoperable for part of the delays.
This is the largest fine ever applied under the tarmac delay rule, which took effect in April 2010. Of the $1.1 million, $475,000 will go to the U.S. Treasury. The remaining $625,000 will cover "mitigation measures for affected passengers and significant corrective actions by United" to keep this from happening again.
The DOT does not have the authority to make airlines compensate their customers.
United did not respond to a request for comment.