US Air Travel Disruptions Hit Third Day, Duffy Expects Normal Monday

JetBlue canceled 27% of its Sunday flights and American Airlines canceled 13%. Southwest, United Airlines and Delta reported cancellations of 3% to 5% of their flights.

The Federal Aviation Administration (FAA) issued a nationwide ground stop on Friday that halted nearly all departing flights for almost five hours. It was the longest nationwide halt to US air travel since the September 11, 2001, attacks.

Officials said FAA contractor L3Harris installed at least one new router at a remote facility. Other air traffic control centers were then overloaded with a flood of data that hampered communications systems.

Duffy said replacing a router at an FAA facility in El Dorado, Arkansas, triggered problems with a recently replaced router in Amarillo, Texas. The Amarillo router started broadcasting and overloaded routers at other control centers across the country.

The FAA said on Sunday it had disabled the "functionality of the originating routers" and did the same for about 60 similar routers. Duffy said the agency still does not know what ultimately caused the problem, which came during maintenance work done thousands of times without issue.

He said the worker who installed the router was "a good American patriot, we believe, a veteran," so officials do not think someone tried to sabotage the network. "But we don't actually have the root cause," Duffy said.

Friday's disruption is the latest sign of strain on an air traffic control system dealing with aging technology, equipment and communications problems and a shortage of several thousand controllers. Duffy said the routers that failed were purchased in 2001 and were obsolete by 2006.

Since Friday, Duffy has called for $50 billion to upgrade air traffic control systems, up from his earlier request of $30 billion. Congress approved $12.5 billion last year.

President Donald Trump made his first public comments on the weekend's problems on Sunday and also called for more funding. "We have already started the work, but it should be done all at once, not in drips and drabs," he wrote on social media. "Congress must approve."

Democrats are set to take control of Congress from Trump's fellow Republicans in January after gains in the November 3 midterm elections. Representatives Rick Larsen and André Carson, the top Democrats on the House Transportation and Infrastructure Committee and its aviation subcommittee, met Duffy's request for more money with skepticism.