UGH: FAA Grounds All Domestic Flights Over Outage.

The Federal Aviation Administration early Wednesday ordered airlines to pause all domestic departures until 9 a.m. ET, to allow the agency to restore a critical system that alerts pilots and crew to safety advisories and other information for flights.

The agency, which oversees and manages the aviation network in the U.S., said it is working to restore its so-called Notice to Air Missions System. “Operations across the National Airspace System are affected,” the FAA press office said. It said it was performing final checks to get the system back up and running.

Passengers on social media were reporting delays early Wednesday, citing the outage, but the scale of the impact wasn’t immediately clear. Some U.S.-bound flights from international destinations such as London and Tokyo were still taking off.

The FAA said in an advisory to operators that a Notam outage hotline had been activated while the problem was being addressed by technicians.

What a mess.