Burbank Airport air traffic control tower unmanned on Monday evening

BURBANK, Calif. (KABC) -- The air traffic tower at Burbank Airport is unmanned on Monday evening as air traffic controllers begin to call out in greater numbers due to the government shutdown.

ABC News was told the air traffic control tower at Hollywood Burbank Airport would be unmanned as of 4:15 p.m. Monday.

The Federal Aviation Administration (FAA) anticipates the airport will be without air traffic controllers until 10 p.m., though they are trying to bring in staffing sooner than that.

Eyewitness News spoke to Burbank Airport air traffic controllers, who confirmed they were heading home at 4:15 p.m. They said they were handing off their duties to Southern California TRACON, an approach and departure team out of San Diego, who will talk to the pilots who will be landing and taking off at Burbank Airport.

Southern California TRACON already remotely handles a lot of the air traffic in SoCal.

Inside Burbank Airport around 4 p.m. on Monday, Eyewitness News looked at the arrivals and departures board, which showed no cancellations and only a few delays.

Officials are hoping for minimal impacts on travelers, but it's unclear what the extent of the impacts may be.

According to an FAA advisory, there are multiple staffing triggers in place, including delays at airports in Denver, Detroit, Indianapolis and Phoenix.

Delays with air travel were anticipated due to the government shutdown, which entered its sixth day on Monday.

Air traffic controllers are government employees and are considered essential, so they have to keep working, but are doing so without pay.

"We are tracking sick calls, sick leave. Have we had a slight tick up in sick calls? Yes. And you'll see delays that come from that, right? Because again, our priority, again, I want to see your flight not be delayed. I don't want you canceled, but our priorities are safety. So if we have additional sick calls, we will reduce the flow consistent with a rate that's safe for the American people," U.S. Secretary of Transportation Sean Duffy said.

Control towers and airport security checkpoints are still staffed, with about 13,200 air traffic controllers and more than 61,000 Transportation Security Administration (TSA) employees expected to remain on the job.

But as more time passes for the workers since their last paycheck, travelers could start to see longer lines at security and flight interruptions, said Jeffrey Price, professor of aviation at the Metropolitan State University of Denver.

"The system does become a little bit more brittle, and the longer this goes, the more the traveler is going to notice it," Price said.

That's what happened in 2018 and 2019, when Trump led the country into its longest shutdown ever for 35 days during his first term.

About three weeks into that shutdown, some unpaid security screeners started calling in sick, and air traffic controllers sued the government in a bid to get their paychecks. Miami International Airport had to temporarily close one of its terminals because TSA officers were calling in sick at twice the airport's usual rate.

The latest shutdown is unfolding at a time when both the TSA and the Federal Aviation Administration are already facing staffing shortages, including a shortage of about 3,000 air traffic controllers.

If the system can't handle the number of flights that are scheduled, the FAA will slow down landings and take offs and passengers will see more delays and cancellations.

Air traffic controllers will receive one more paycheck, which is essentially half of a paycheck since the shutdown began in the middle of a pay period. They will get the pay for what they worked before the shutdown next Tuesday. They will eventually be paid again once the shutdown ends.

The Associated Press contributed to this report.