The US Federal Aviation Administration (FAA) lifted a nationwide ground stop on all departing flights early on Saturday, hours after a communications failure at air traffic control facilities halted take-offs across the country.
The Department of Homeland Security said there was no threat to the public.
What Happened
The FAA ordered all departures from US airports grounded at 20:54 UTC on Friday, citing a communications problem affecting its Air Route Traffic Control Centres. Flight-tracking service Flightradar24 said 4,042 flights were already in the air when the order was issued, and those aircraft continued to their destinations.
The order was lifted at about 7.11 a.m. IST on Saturday, allowing airlines to begin resuming departures. Carriers warned that knock-on delays and cancellations would continue through the day.
Second Such Shutdown Since 9/11
The stoppage is only the second nationwide ground stop since the September 11, 2001 attacks. The first came in January 2023, when the FAA briefly paused all domestic departures for less than two hours after a failure in a critical notification system.
Cyberattack Ruled Out, For Now
Homeland Security Secretary Markwayne Mullin said authorities were still investigating, but there was no sign of a hostile attack. He described the disruption as a telecommunications outage and said officials had found nothing to suggest a deliberate act.
ALSO READ: US Flights Grounded LIVE: Nationwide Shutdown Lifted, Officials Assure 'No Threat To Public'
Ageing Systems Blamed
Transportation Secretary Sean Duffy said ageing equipment was to blame. He said legacy systems were overloaded with data, and that routers failed under the strain. Controllers then shut the system down to prevent further problems.
Duffy used the episode to renew his call for Congress to fund a full overhaul of the country's air traffic control infrastructure, saying the existing technology was analogue and unfit for a system that carries millions of passengers. He said the funding was not a partisan issue.
Impact On Travellers, Including India Links
American Airlines said its operations would face disruption for the rest of the day, depending on how quickly the backlog cleared. Air India issued a travel advisory warning that flights to and from the US could be affected and asking passengers to check flight status before heading to the airport.
Aviation analysts say the full cost of the shutdown, in crew repositioning, missed connections and rebooking, may take days to assess. The airlines have not yet put a figure on losses.
ALSO READ: US Flight Shutdown Lifted: Cause, Impact And More In 10 Key Points
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