Flights have been given the green light to resume across America after an “extraordinary circumstance” prompted the US Federal Aviation Administration to order a national ground stop.
The rare order, which grounded departing flights at airports across the country on Friday, was lifted after officials addressed the “safety concerns.”
The FAA ordered the hours-long ground stop shortly after it halted traffic in Chicago due to air traffic control communications issues.
Air travel across the globe was thrown into chaos as aircraft operators were instructed to keep all departing traffic on the ground until further notice.
US Transportation Secretary Sean Duffy confirmed at a press conference the ground stop order had been lifted, but warned severe delays were expected.
“If you are watching, if you are at an airport, check with your airline, it depends on do we have crews available,” he said.
“We are going to try to move as many as those as we can tonight if we have capacity.
“If not, we are going to start tomorrow morning with our airline partners to move those aircraft but is going to take us some time to unwind what has happened this afternoon.”
Flight tracking service FlightAware said nearly 7,000 flights were delayed or cancelled due to the nationwide ground stop.
In an earlier update,Mr Duffy said the incident, believed to be caused by a “communication issue”, was being investigated.
“The FAA issued a nationwide ground stop for all US airports following a communication issue impacting all Air Route Traffic Control Centres. FAA technicians are investigating the issue,” he said.
“We will provide immediate updates as we have them.”
US Homeland Security Secretary Markwayne Mullin reassured passengers were not in danger as there was so far no indication of a nefarious act.
“We had no reason to believe that — as of right now, that this was a threat to the United States,” he told reporters in Washington.
“It’s just a telecommunications outage … everybody’s safe. There’s no reason to be concerned about your loved ones if they’re flying.”
When asked if the incident could have been caused by a cyber attack, Mr Mullin said this isn’t “another 9/11” adding that officials would not yet rule out any potential causes.
Friday’s halt was the second nationwide ground stop of all departures since the September 11, 2001, attacks. The other happened in January 2023, when the FAA paused all domestic departures for less than two hours.
Back on Australian soil, travellers heading to the US were urged to check their flight details as the aviation incident continues to cause delays.
Sydney Airport said flights bound for the US had been halted despite the ground stop being lifted, urging travellers to look out for further updates from their airline.
“We are aware of the nationwide ground stop issued by the US Federal Aviation Administration and are monitoring the situation closely,” a spokesperson said in a statement provided to 7NEWS. .
“At this stage, some US bound flights due to depart Sydney Airport are grounded.
“Passengers travelling to or via the United States should check with their airline for the latest information regarding their flight.”
Qantas issued similar advice to its passengers, saying the outage was yet to affect its operations.
Australian Travel Industry Association (ATIA) said Australians travelling to the US in the next 72 hours should get in touch with their airline, tour operator or travel agent if they had not been contacted already.
“It is a developing situation, and there will be knock-on impacts for travellers,” the nation’s peal travel industry body said in a statement.
with NCA Newswire
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