United Airlines resumed operations after it was forced to temporarily ground all mainline flights due to a technology issue, causing delays as the airline worked to resolve the problem.

United Airlines issued a nationwide ground stop for all mainline flights on Thursday after its Chicago operations center experienced an emergency alarm. According to a statement from the airline ...

Travelers were left scrambling Wednesday as United Airlines planes were suddenly grounded and more than 1,000 flights delayed across the U.S.

"Engine failure, left engine," a pilot can be heard saying in cockpit audio shared online. "Mayday, mayday, mayday." ...