Transportation Secretary Sean Duffy warned there will be a 10% reduction in air travel capacity at 40 major U.S. airports starting Friday if the government shutdown continues.
The decision is because air traffic controllers have reported fatigue problems, the head of the Federal Aviation Administration (FAA) said in a briefing with Duffy.
“It’s unusual, just as the shutdown is unusual, just as the fact that our controllers haven’t been paid for a month is unusual,” FAA Chief Bryan Bedford said.
Some 1.4 million federal workers, from air traffic controllers to park rangers, are working without pay – or are on furlough – because Congress has not agreed to a federal funding budget.
Unions say many employees are falling ill from stress or being forced to take second jobs as financial pressure hits what is now the longest shutdown in U.S. history.
The flight reductions will be gradual, starting with 4% of domestic flights on Friday, then increasing to 5% on Saturday and 6% on Sunday, before reaching 10% next week, Reuters reported after the announcement, citing four unnamed sources.
The names of the affected airports, all of them high-traffic locations, will be released Thursday, officials said.
The cancellations could affect between 3,500 and 4,000 flights daily.
“We’re seeing pressures build in a way that we don’t believe, if we allow it to go unchecked, will allow us to continue to tell the public that we operate the safest airline system in the world,” Bedford said.
Duffy said air travel remains safe and the decision to cancel flights was made to maintain safety and efficiency.
If the shutdown continues and adds more pressure to the system, additional restrictive measures may be required, Bedford said.
In a statement, American Airlines, North America’s second-largest airline, said it was awaiting additional information from the FAA so it can determine which flights will be canceled, but that “we expect the travel of the vast majority of our customers will not be affected.”
A spokesperson for Southwest Airlines, the fourth-largest airline, said in a statement that the company is still evaluating how the flight restrictions will affect its services, and will notify customers as soon as possible.
“We continue to urge Congress to immediately resolve their impasse and restore the National Airspace System to its full capacity,” the spokesperson added.
Delta Airlines declined to comment. The BBC has also contacted other major US airlines.
Once government funds ran out on October 1, most federal workers were sent home and told they would be paid once the government reopened. However, those considered essential, such as controllers, had to continue doing their work without pay.
Almost immediately after the shutdown began, airports began to feel the effects. Some had to suspend flights for hours after air traffic controllers called out sick, while others relied on controllers at other airports.
Nick Daniels, president of the union that represents more than 20,000 aviation workers, put the situation in stark terms Wednesday.
“Air traffic controllers text: ‘I don’t even have enough money to put gas in my car to go to work,'” he told CNN.
“We base what we do day in and day out on predictability,” he said. “Right now there is no predictability.”
Duffy warned earlier this week that flight cancellations are possible as half of the country’s top 30 airports experience staff shortages.
He previously said there is a risk of air traffic controllers taking on additional jobs during the lockdown, and had threatened to fire controllers who did not turn up to work.
“They have to make a decision: Do I go to work and not get a paycheck and not put food on the table? Or do I drive for Uber or DoorDash or wait tables?” Duffy said on ABC on Sunday.
