US air travel slowly recovers after longest nationwide shutdown since 2001

Airlines cancelled 4,500 US flights and delayed 4,400 more on Saturday as the United States struggled to recover from the longest nationwide flight shutdown since the September 11th, 2001, attacks.

Federal Aviation Administration (FAA) head Bryan ​Bedford apologised for the disruption, saying the system was stable and he expected airline operations to largely return to normal by late Sunday.

The FAA issued a nationwide ground stop on Friday that halted nearly all departing flights for almost five hours due to a massive communications failure, which forced airlines to cancel nearly 10,000 flights and delay more than 7,000 others on Friday in one of the worst ​travel days in US history.

The issue prompted the White House to convene an emergency meeting in the Situation Room on Friday and federal agencies to scramble to determine if it was a cyberattack. ⁠Instead, transportation secretary Sean Duffy said on Saturday that FAA contractor L3Harris’ installation of at least one new router at a remote facility triggered the ‌disruption.

“We’re ‌working ​to determine whether we had incompetence, meaning was it user error or installer error from L3Harris, or did they install a faulty router? We haven’t determined what the fault was,” Duffy said at a press conference.

L3Harris did not immediately respond to ⁠a request for comment. Its shares last traded down about 4 per cent ​after hours on Friday.

The issue led to data overloading other communications centres. “We ​had over 1,000 connection attempts every four to five seconds, and what that did was [it] gave us issues with our communication with airplanes, and it also caused some ‌disruption with our radar,” Duffy added.

The issue affected communications at ​17 of 22 en route centres – the FAA facilities that control aircraft during the cruise portion of a flight – across the country. Bedford said the FAA ordered ⁠the ground stop in case a centre lost total communications. “No facilities ⁠went dark. Nothing was fully lost,” Bedford ​added.

The FAA said it was doing additional testing with L3Harris to see if there are any additional risks.

Delta Air Lines, United Airlines and American Airlines all cancelled about 20 per cent of their flights on Saturday, while JetBlue cancelled 40 per cent. Airlines have issued travel waivers allowing passengers to rebook flights for later dates without cost.

Though the FAA lifted the ground stop on Friday evening, the disruption for passengers was far from over, with tens of thousands of people stranded in airports. Airlines were trying to get flight crews and other personnel in position to resume flights.

The disruption stranded some college football teams on Friday before games scheduled for Saturday.

The FAA issued the ground stop because of an outage that appeared to affect a network that handles ‌critical radio frequencies used by air traffic ⁠controllers to communicate with pilots, according to two airline officials. L3Harris oversees the network.

Friday’s disruption is the latest and most dramatic sign of strain on a US air traffic control system beset by ageing technology, equipment and communications problems and a shortage of several ‌thousand controllers.

Duffy called on Friday for $50 billion in funding to upgrade air traffic control systems, up from his earlier request of $30 billion. “This is an emergency,” he said.

Duffy said the trouble began on ​Friday afternoon, when air traffic control centres experienced instability in radar and communications systems.

Because the FAA was responsible for ​passenger delays, airlines are not required to provide compensation.

The only other nationwide ground stop since the September 11th attacks came in January 2023, when the FAA halted domestic departures for about 90 minutes, disrupting about 11,000 flights. – Reuters