The nationwide grounding that halted all air travel nationwide and stranded thousands of passengers has been canceled, according to the Federal Aviation Administration. Within minutes of air traffic being restored, Sean Duffy, the Transportation Secretary, took to a podium Friday night at the White House to criticize Congress, accusing lawmakers of dragging their feet when it came to fully funding improvements he warned were vital to preventing similar failures from happening again. “It’s going to keep failing,” Duffy said. reporters, adding: “How many times does this have to happen before Congress gives the money to fix it?” Duffy added that the antiquated radar and telecommunications systems that controllers rely on to transmit data and other information between the facilities began to fail around 3:36 p.m. The old system, which has undergone a series of upgrades, became overloaded, officials said. Appearing alongside him, Markwayne Mullin, the secretary of homeland security, emphasized that there was never any indication that the communications failures had been caused by a cyber attack, but added: “We’re still looking, and I’m not going to rule it out.” He stressed that lives were never in danger. But the incident appeared to inject new fuel into Mr. Duffy’s months-long campaign to secure at least $30 billion in additional funding for air traffic control modernization. Last year, Congress approved $12.5 billion to upgrade aging air traffic facilities and technology, funds that Mr. Duffy has repeatedly referred to as a “down payment” when calling for tens of billions more. On Friday night, Duffy appeared to up the ante, telling reporters that he not only wanted another $30 billion for the project, but another $50 billion. He argued that it should be delivered in the form of emergency funds before the end of the year, after which control of Congress – and the budget – will shift from Republicans to Democrats. Some Democratic lawmakers have already raised questions about the efficiency and effectiveness with which the FAA has spent the money it has given them so far. But Duffy has long argued that his department cannot be expected to complete a significant overhaul of the nation’s air traffic control system without a massive influx of funding. Friday’s nationwide ground stop was only the third the FAA has issued this century. It ranks as the second longest, after the ground stop issued on September 11, 2001, following the terrorist attacks on the World Trade Center in New York. There was a shorter one on January 11, 2023, due to an outage in the FAA’s system for alerting pilots to safety issues. Friday’s order halted nearly all departures and left thousands of passengers stranded at airports across the country. Hundreds of flights were diverted to other airports and more were cancelled, even as some international flights managed to gain permission to take off. Amid the delays and cancellations, many passengers were pulled from flights or told to return home. More than 2 million people pass through airport security checkpoints on a typical day, according to data from the Transportation Security Administration. On Thursday, the agency tested nearly 2.5 million people. According to FlightRadar24, an aviation tracking site, there were more than 1,000 planes in the air bound for U.S. airports during the nationwide grounding. According to the flight tracking app Flighty, there were more than 30,000 departures and arrivals scheduled for the rest of the day. Passengers waiting to take off on Friday afternoon were stuck in limbo. At the Denver airport, passengers were removed from their flights with their suitcases. A handful began changing travel reservations for the next day. But most waited patiently for any kind of update. A Southwest flight attendant announced that the airline expected an update in 30 minutes. Before the notice was published, the FAA halted flights to Chicago’s O’Hare and Midway airports, citing equipment problems, and reported departure delays related to equipment at Newark, Las Vegas, Teterboro, Orlando, Houston and Phoenix. Here’s what you need to know: If your flight is canceled: You are entitled to a refund if your flight is canceled in the United States, regardless of the reason, or if a flight is delayed or changed significantly and you decide not to take it. Here are some other travel tips that may be helpful. Read more ›A busy travel month: The ground stop came about two weeks before Thanksgiving, one of the busiest times of the year for air travel. On average, U.S. airlines are expected to carry about 2.7 million passengers each day during the holiday period, according to industry trade group Airlines for America. The last ground stop: The last national ground stop occurred in the early morning of January 11, 2023 and lasted around 90 minutes. The outage came after a system to alert pilots to dangers in real time failed. Read more ›Christine Chung, Niraj Chokshi, Luke Broadwater, Dustin Volz, Lisa Lerer and Robert Chiarito contributed reporting.