After briefly grounding all departing flights in United States on Friday, the Federal Aviation Administration lifted the nationwide ground stop as the Homeland Security said there was no threat to the public.

The Federal Aviation Administration had briefly grounded all flights departing United States due to an air traffic control communication issue.

Dismissing the possibility of a cyberattack, U.S. Homeland Security Mark Wayne Mullin briefing the press said that authorities were investigating the incident.

“There was no indication, as of yet, that this was a nefarious attack against us. It’s just a telecommunications outage, as of right now,” Mullin said.

“This isn’t another 9/11. I just can’t repeat that enough,” he added.

He also quashed claims that the outage today has anything to do with the Microsoft outage many experienced yesterday.

US Transportation Secretary Sean Duffy followed up by saying the reason for the system outage is clear – it is old, he says, with old routers, and it’s a “national security risk”.

“We’ve got our centres and our trachons operational right now, and so at 8:15 tonight Eastern time, we’ve opened up the airspace.But flight movement depends on resources, he added.”

This was the second largest ground stop of flights since September 11, 2001. The other happened in January 2023 when the FAA paused all domestic departures for less than two hours.

Citing the nationwide ground stop, Air India issued an advisory to passengers. Taking to X formerly known as Twitter, informing its passengers it wrote, “A nationwide ground stop is currently in effect across the US due to communication outages affecting air traffic operations. As a result, departures from airports across US are impacted, with possible consequential disruptions to Air India flights to and from the US. Passengers are advised to check the latest status of their flights and plan their journey to the airport accordingly,” it wrote in a post on X.

American Airlines also issued notice a notice to its passengers about the disruption of services.

As per data by Flight radar agencies over 4,000 flights were already airborne as U.S. orders ordered nationwide ground stop.

Though the grounding notice was lifted the ripple effect will be seen for a few days. It remains to see how the US Aviation Administration manages the flights as hundreds are stranded at the international airports.