Here’s what we know so far about the US flight shutdown, and what it means for travel

US Transportation Secretary Sean Duffy confirmed that the Federal Aviation Administration (FAA) issued the ground stop following a system-wide failure involving Air Route Traffic Control Centres.

In a post on X, Duffy said: “FAA technicians are investigating the issue. We will provide immediate updates as we have them.”

What have the FAA said?

The FAA has attributed the nationwide disruption to “extraordinary circumstances”, but has yet to disclose further details about the incident.

The Department of Homeland Security has also said there is currently no indication that the communications failure was caused by foul play.

At this stage, the exact cause of the failure has not been specified. Further updates are expected as the FAA continues to investigate the communications failure.

When was the last time this happened?

A nationwide ground stop of this scale is an extremely rare occurrence in US aviation history.

It is understood to be only the third time such an order has been issued nationwide. The first occurred following the September 11 terrorist attacks in 2001, while the second took place in January 2023 after the FAA’s Notice to Air Missions (NOTAM) system suffered an outage.

Is AI to blame for this?

The communications failure comes just days after the FAA announced plans to begin rolling out an AI system across the US to help air traffic controllers manage traffic and prevent delays, The New York Times has reported.

The timing has raised questions. According to the report, the AI technology was first unveiled at Washington DC airports two months ago on the same day a separate communications failure grounded hundreds of flights.

That earlier outage was caused by a circuit failure after contractors accidentally cut through a backup fibre line.

University of Sydney aviation professor Rico Merkert said: “It’s really important to have modern infrastructure in this space and without that, you can add as much AI as you like to those systems, but if you don’t have that proper ground infrastructure there, then it’s that’s not functional.”

What does this mean for travellers?

The ground stop is expected to cause widespread disruption across the US aviation network, with delays and cancellations likely to have knock-on effects throughout the day.

The Australian Travel Industry Association CEO Dean Long said it was a developing situation for Australian travellers which will have “knock-on impacts”.

For travellers who have booked through an ATIA-accredited travel business, “expect to hear from them or your airline”.

“If you’re travelling in the next 72 hours, that’s our priority.”

“If you haven’t heard from your travel agent, tour operator or airline yet, get in touch with them.”

For those not flying within 72 hours, they should hold off communicating with travel agencies and airlines “so they can look after the travellers who need it most urgently.”

“We know this is unsettling for travellers,” Long said. “Our members are there to help, and we are monitoring the situation closely.”

In an update released at 10am AEDT, the FAA said the ground stop remains in place but “as en route facilities recover, flights will be allowed to depart” – with flights being released gradually as air traffic control centres recover.

For Australian travellers flying to the United States, airports are monitoring the situation and advising passengers to check directly with their airlines.

• Sydney Airport: All domestic and international flights are operating as normal, with no current impact to airport operations.
• Melbourne Airport: Passengers booked on morning departures are advised to proceed to the airport as planned until further notice.
• Brisbane Airport: American Airlines flight AA008 to Dallas Fort Worth has been delayed by one hour, moving from its scheduled 9.40am departure to 10.40am. The airport has advised passengers to check with their airlines for updates.

Sydney Airport said it was monitoring the situation closely, but there was currently no impact to its operations.

“Passengers travelling to or via the United States should check with their airline for the latest information regarding their flight,” a spokesperson said.

Qantas have advised at this stage there is a limited impact for the airline, but passengers are advised to check for updates through the app – though flight QF4 (New York to Auckland) is expected to be delayed. Most US-bound Qantas flights depart in the afternoon, providing a buffer while the FAA issue is resolved.

Meanwhile, US airlines have warned passengers to expect disruptions.

United Airlines confirmed that flights already airborne would continue to their destinations, but new domestic departures would remain grounded while the FAA order was in place.

United is proactively cancelling flights due to congestion in the nation’s air traffic system, and issuing travel waivers, so customers can change their travel plans.

Chris Zappone is a senior reporter covering aviation and business. He is former digital foreign editor.Connect via X, Facebook or email.