US airline company Delta says all its flights have been suspended due to a nationwide system outage.
"Customers should check the status of their flight before heading to the airport while the issue is being addressed," the company tweeted.
It said it was working to resolve the issue as soon as possible. Inbound flights en route are not affected.
Delta serves nearly 180 million customers a year, employing over 80,000 people, according to its website reports the BBC.