Passengers reported American Airlines flights being delayed across the United States Sunday afternoon, with word from pilots and staff suggesting a serious computer outage was the culprit. The FAA now says the issue has been resolved, but the impact of the delays is likely to continue at least over the next few hours.
On Twitter, passengers Sunday reported delays in cities from Columbia, S.C. to Detroit. Staff on the ground reportedly described the problem as “systemwide.”
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The Federal Aviation Administration told reporters that the issue was resolved around 2:50 p.m. ET this afternoon, but that it caused a “nationwide ground stop.”
American Airlines issued a statement to Fortune after the outage was resolved:
“American Airlines experienced a brief connectivity issue with one of its data centers, that has now been resolved. We apologize to our customers for the inconvenience and all operations are returning back to normal.”
American confirmed that the ground stoppage lasted roughly 30 minutes. Because of the interlocking dependencies inherent to airline scheduling, a nationwide stoppage of that length could cause ongoing delays to subsequent flights, but American says there were no cancellations as a result of the network failure.
Update 4:26 ET: This story has been updated to reflect additional information from American Airlines.