Air travel across the U.S. may soon experience major disruptions as the government shutdown continues to affect essential aviation workers. Transportation Secretary Sean Duffy confirmed that there’s been a rise in sick calls among air traffic controllers, who are required to work without pay.

"In a job that's already stressful, this shutdown has put way more stress on our controllers," said Duffy during a press conference on Monday.  "So we're tracking sick calls, sick leave, and we had a slight tick up in sick calls, yes. And then you'll see delays that come from that." 

The National Air Traffic Controllers Association, which represents more than 20,000 members, urged workers to remain professional and committed despite growing strain. In a message to members, the union wrote that it is “more important than ever that we rise to the occasion and continue delivering the consistent, high level of public service we provide every day.”

Meanwhile, TSA officers—also federal employees working without pay—are asking travelers for patience. According to TSA, about 50,000 agents are continuing to screen 2.5 million passengers per day nationwide. The agency warned that an extended shutdown could turn into substantially longer wait times at airports. 

The Modern Skies Coalition, which includes major airlines like United, Delta, and American, recently sent a letter to Congress warning that shutdowns harm the U.S. economy and degrade the redundancies and margins of safety that our National Airspace System is built upon.

With air traffic control staff already overextending themselves and TSA officers working unpaid, travelers are being advised to prepare for longer lines, significant flight delays, and general disruptions if the shutdown drags on.