The shutdown in Washington has caused grounded or delayed flights in airports across the country.

Air travel was crippled across the U.S. this weekend. Blame is on staffing shortages.

TSA agents and air traffic controllers are still on the job, but they're not being paid. Controllers will miss their first full paycheck on Tuesday.

"They get a notice of what they're going to be paid on Tuesday, and they got a big fat zero, no paycheck is coming on Tuesday, and so I've been out talking to our air traffic controllers. And you can see the stress," Transportation Secretary Sean Duffy told Fox News Channel's "Sunday Morning Futures."

The FAA issued 22 "staffing triggers" on Saturday — a designation of understaffing of air traffic controllers.

More than 8,000 U.S. flights were delayed on Sun

See Full Page