Here’s Why United Flights Were Grounded This Morning

United Airlines flights were grounded briefly Tuesday morning due to unspecified “automation issues.” United attributed the delay to faulty flight information in the airline’s dispatch system.

“United began delaying flights at approximately 8 a.m. CT to ensure aircraft departed with proper dispatching information,” United spokesperson Charles Hobart wrote in an emailed statement to TIME. “We resumed departures at about 8:40 CT and are accommodating our customers to their destinations.”

The Federal Aviation Administration issued a temporary advisory notice early Tuesday morning stating that the ground stop applied to all United Airline flights on Tuesday morning. The advisory was lifted just a few minutes later.

Stranded passengers took to Twitter, describing extended wait times on the tarmac.

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