The Federal Aviation Administration said normal air traffic operations are resuming across the United States following an overnight outage to its Notice to Air Missions (NOTAM) system which provides safety information to flight crews.
"The ground stop has been lifted," the agency said in an update shortly before 9am Eastern Time. "The agency continues to look into the cause of the initial problem."
Earlier on Wednesday, the agency ordered airlines to pause all domestic flight departures in the United States until 9am as the agency works to restore NOTAM.
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In a tweet posted at about 8.15 am, the agency said departures were resuming at Newark Liberty International Airport (New Jersey) and Atlanta Hartsfield-Jackson Airport (Georgia) due to air traffic congestion, with departures to resume at other airports at 9 am.
“We are performing final validation checks and reloading the system now,” the FAA said. “Operations across the National Airspace System are affected.”
The agency noted that the NOTAM system “alerts pilots about closed runways, equipment outages, and other potential hazards along a flight route or at a location that could affect the flight.”
“Flights currently in the sky are safe to land,” they added in a tweet. “Pilots check the NOTAM system before they fly.”
Full investigation into outage ordered by President Biden
US president Joe Biden has been briefed by Secretary of Transportation Pete Buttigieg on the system outage and has directed the Department of Transportation to conduct a full investigation into the causes, White House Press Secretary Karine Jean-Pierre said in a tweet.
“There is no evidence of a cyberattack at this point,” she noted.
Reed Smith US-based aviation lawyer Patrick Bradley said the outage led to more than 10,000 flight delays just before 9am on Wednesday, citing the flight-tracking website FlightAware.
He noted that federal agencies like the FAA depended on stable Congressional funding to ensure their critical systems were operable and maintained.
With the FAA's current authorization mechanism, the Reauthorization Act of 2018, expiring in fall 2023, Bradley stressed the importance of industry support to help the FAA set forth its legislative priorities before Congress.
"These delays and cancellations affect the bottom line of a myriad of airlines, many of which were recently affected by weather over the holiday season," Bradley said.
US airline share prices edged lower in pre-market trading but had largely recovered by midday, with United Airlines Holdings Inc (NASDAQ:UAL) up 3.3%, Delta Air Lines (NYSE:DAL) Inc up 1.4%, American Airlines Group (NASDAQ:AAL) Inc up 1%, with Southwest Airlines Co lagging, down 0.7%.
— Updated with additional commentary —
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