United Airlines grounded a large number of its flights in the U.S. on Wednesday evening after it says it discovered a technical issue in its network.
United told Scripps News Group in a statement that it had stopped departures of all its main flights from U.S. airports on Wednesday due to a "technology issue."
The problems affected computer systems that tracked flight information, including flight times, as well as safety systems that monitored the physical loading and balance of aircraft.
The stop did not apply to some regional partner operations run under United Airlines and did not apply to any United Airlines aircraft currently airborne to their destination.
United said later on Wednesday evening it had resolved the initial computer troubles within a few hours.
As of early Thursday morning, some flights remained canceled or delayed. FlightAware reported that 4% of United Airline flights for Thursday had been canceled, while another 4% of flights for the delay had been delayed.
On its travel alerts page Thursday, United said customers may continue to experience delays at airports in Denver, Cleveland, New Jersey, New York, Hawaii, Houston, Los Angeles, Orlando, Chicago and San Francisco, as well as at airports abroad including Frankfurt, London and Munich.
"We are working with customers to get them to their destinations after a technology disruption on Wednesday evening," the airline said in a statement. "The underlying technology issue has been resolved, and, while we expect residual delays, our team is working to restore our normal operations."
