Passengers await updates on grounded United flights at O'Hare. (Andrew Lahey/Twitter)

Passengers await updates on grounded United flights at O’Hare. (Andrew Lahey/Twitter)

(CBS) — United Airlines said it has worked through computer network problems that grounded all of its flights, including those at O’Hare International Airport, for about two hours Wednesday morning.

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“We are recovering from a network connectivity issue this morning and restoring regular flight operations. We will have a waiver available at for customers who are able to change their flight plans,” the airline said in a prepared statement.

“An issue with a router degraded network connectivity for various applications, causing this morning’s operational disruption. We fixed the router issue, which is enabling us to restore normal functions.”

Reports of the outage first surfaced around 8 a.m. Chicago time, and Twitter was flooded with observations and pictures from stranded air travelers. CBS 2’s Vince Gerasole said the United terminal at O’Hare was no longer crowded with a backlog of passengers by mid-morning.

It’s the second time in two months that the Chicago carrier has been hit by major technical issues, the Associated Press reports.

United had a temporary halt to all takeoffs in the U.S. on June 2 because of what the airline said were computer automation issues.


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CBS 2’s Suzanne Le Mignot spoke with Aaron Gellman, a former professor and director at the Transportation Center at Northwestern University.

“Computers basically touch every virtually aspect of the airlines operations,” Gellman said. “You can’t be anything but reliable, where those systems are concerned, lest you pay a terrible price.”

Gellman says the outages will cost the airlines millions of dollars.

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