US grounds flights for five hours as air traffic system fails; 827 flights diverted

Washington: Air travel across the United States was thrown into disarray on Friday after the Federal Aviation Administration ordered a rare nationwide halt to flight departures, leaving thousands of passengers stranded and forcing airlines to divert hundreds of flights.

The ground stop, imposed at around 3:54 pm Eastern Time, remained in place for more than four hours before being lifted at 8:15 pm. It was the first such nationwide suspension of departures since January 2023 and only the second since the September 11, 2001, terrorist attacks.

Officials said the disruption stemmed from communication failures and radar gaps at regional air traffic control centres, raising fresh concerns over the condition of America's ageing aviation infrastructure.

Trump administration officials indicated that newly installed technology may have overloaded the country's outdated air traffic control network. Homeland Security Secretary Markwayne Mullin said the FAA had been rolling out new equipment and systems, which appeared to have overwhelmed the older infrastructure.

Transportation Secretary Sean Duffy said 3,500 aircraft were in the air when the order was issued. That number later dropped to fewer than 400 as flights landed. Mullin said over 3,000 flights landed safely and no passengers faced danger.

When asked whether a cyberattack or an artificial intelligence-related failure could be behind the outage, Mullin said there was no definitive answer yet. He said investigators had not found any signs of a malicious attack and that the problem appeared to be mechanical in nature.

Aviation analytics firm Cirium reported that at least 827 flights were diverted during the disruption. Of these, 670 returned to their original departure airports, while 157 were redirected to alternate airports.

Cirium estimated that around 11,000 flights carrying more than 1.5 million passengers were scheduled to depart after 4 pm EST. Flight tracking data showed that over 15,000 flights were either delayed or cancelled across the day.

At Chicago O'Hare Airport, travellers discovered the scale of the disruption only after seeing delay messages flash across departure boards. Many scrambled to contact family or friends to decide whether to wait overnight or seek alternative routes.

The shutdown also hit professional and collegiate sports. NBA, NHL and college teams were left stranded mid-journey, while NFL teams waited to see whether the system would be restored in time for weekend fixtures.

Cargo operations were similarly affected. FedEx said it stood ready to activate contingency plans to limit disruption. Despite the chaos, SpaceX went ahead with its Starship rocket launch from Texas on Friday afternoon.

Although a limited number of domestic flights resumed on Friday evening, airlines warned that full recovery could take several days. Officials expressed hope that the system would stabilise before the Thanksgiving travel rush.

The incident has reignited debate over the state of America's air traffic control infrastructure. Congress approved USD 12.5 billion last year for modernisation, with old copper wiring being replaced by fibre optic lines and legacy radio systems gradually upgraded. Duffy has said an additional USD 30 billion is needed, and the White House has begun pressing Congress for the funds.

Aviation safety expert and former United Airlines pilot Steve Arroyo said the nationwide scope of Friday's failure was unprecedented in recent memory. He said controllers were left unable to reliably communicate with pilots, making it unsafe to allow further takeoffs.