As the federal government shutdown stretches into its seventh day, turbulence is mounting across the nation’s airports. The Federal Aviation Administration (FAA) now warns of a possible ground stop in Houston—an extreme measure that could ripple across the country.

Meanwhile, at Dallas/Fort Worth International (DFW) and Love Field Airport, flights are still departing and arriving, but local officials and unions warn the situation could change quickly.

Just before 5 p.m. Tuesday, the FAA listed DFW with a departure delay.

“Avg. 30 mins. (and decreasing) Due to staff: staffing,” the FAA website said.

Later, it listed Dallas Love Field experiencing a one-hour delay.

At DFW, some travelers arrived early, prepared for the worst.

“I had been seeing so much about it on the news, and I didn’t really know what to expect since it happened last week. So whenever I was like, ok, I’m not missing a flight. I’ve got to get here early, so I’ve been here for like six hours just waiting to see what’s going to happen, how long are the lines?” said Katelyn Schwartz ahead of an 18-hour flight to Australia.

According to FAA officials, if staffing shortages worsen, Houston’s airports could be placed under a ground stop as soon as Tuesday evening.

A ground stop is listed as “probable” for George Bush Intercontinental Airport on the FAA’s website.

Staffing shortages have also triggered changes at Hobby Airport in Houston. According to the FAA’s website, Hobby has a “possible” ground stop.

Such a move would strand flights in the air or force reroutes, having a domino effect across the national airspace.

Johnny Jones, President of Local 1040 of the American Federation of Government Employees at DFW, acknowledged that operations are smooth for now, but cautions that memories of the 2018–2019 shutdown are fresh.

“I’m not saying that they’re calling on sick for other than whatever their normal reasons would be. But as you get longer into the shutdown, like the one back in 2018, 2019, folks literally didn’t have the funds to go to work. They’re probably not there yet, but if they go another week or so, this could be starting to become a challenge for some of my co-workers,” Jones said.

He warned that as the shutdown drags on, essential employees may struggle to stay on the job without pay.

“There’s a lot of uncertainty, lot of questions coming from the field. They don’t know how long this is gonna last,” Jones said. “They’re not gonna get a full paycheck, so their next paycheck is gonna be partial already because of the way that this shutdown started. And that’s definitely a concern for a lot of the employees.”

On Monday, the Transportation Secretary Sean Duffy said the early impacts are already surfacing at other major airports.

“We’re tracking sick calls, sick leave, and have we had a slight tick up in sick calls? Yes, and then you’ll see delays that come from that,” Duffy said.

Duffy and other officials emphasize that while air travel remains safe, the system is under mounting pressure.

“What the consistent message was from these controllers was they’re not just now thinking about the airspace and the jobs they have to do in these towers or tracons or centers across the country, they’re thinking about, ‘Am I going to get a paycheck?”” Duffy said. “So, in a job that’s already stressful, this shutdown has put way more stress on our controllers.”

Foundation for Aviation Safety Flight Safety Officer Randy Klatt said the system simply isn’t equipped for added strain.

Flight delays continued for a second day across the country as the government shutdown impacts air travel. Air traffic controllers are working without pay, and sick calls are on the rise, with more than 3,000 flights delayed nationwide and hundreds in North Texas. NBC 5’s Allie Spillyards reports from Dallas Love Field.

“Today, we are somewhere between 60 and 70 percent manned across the country. So when you put any sort of stressor on the system, such as a government shutdown in this case, or what we saw happen in Newark earlier this summer, yeah, inevitably we’re going to have interruptions in air and air traffic system,” said Klatt.

While he said those shortages don’t necessarily make flying unsafe, they could decrease the margin of safety.

“We’re working people harder, they’re working longer hours, they’re a little apprehensive about their job security and everything else that goes with that. It just increases the likelihood of a mistake that could be costly,” he said.

The FAA has reported delays at Newark, Denver, and Burbank tied to controller absences. In Newark, controllers and union representatives said more staff are calling in sick rather than working without pay.

However, until Congress acts, the risk of worsening staff shortages, compounding delays, and potential ground stops in critical hubs like Houston remains.