Delta was hit by a crippling computer outage on Sunday night that caused big delays and the cancellation of many flights.
It’s the second time in less than six months that the U.S. carrier has suffered a major IT problem resulting in travel chaos and angry passengers.
The FAA announced a nationwide ground stop late Sunday on all domestic Delta flights. The measure remained in place for at least two and half hours until it was lifted.
Delta said its IT systems were starting to return to normal and flights were taking off again.
But more cancellations were expected and it was unclear how much of the disruption might spill into Monday.
The airline’s website and mobile apps also went down, adding to customers’ frustrations.
Delta said that flights already in the air weren’t affected by the outage but that some passengers were experiencing delays after landing.
“I want to apologize to all of our customers who have been impacted by this frustrating situation,” Delta CEO Ed Bastian said in a statement. He didn’t specify what had caused the computer problems just months after the airline’s previous system failure.
The FAA said in its advisories that Delta’s international flights weren’t affected by the ground stop.