Thousands of flights have been delayed across the country this week as the government shutdown enters its eighth day.

In fact, more than 2,500 flights were delayed just today.

In an interview with Fox News, Transportation Secretary Sean Duffy said controllers calling out sick were a significant reason for the huge spike in delays.

Historically, there's about a 5% of delays that is attributed to staffing issues in our towers.

The last couple of days it's been 53%.

And so my message to the air traffic controllers who work for DOT is show up for work.

The bottom line is these controllers are stressed out

and they're rebelling on this shutdown because they may not get paid. They're working six days

a week. They're keeping America operational and they're not guaranteed a paycheck and

they're frustrated by it.

Air traffic controllers have reportedly called out sick in large numbers in Las Vegas, Denver, Phoenix, Chicago, and Newark.

Earlier this week, Burbank Airport didn't have any controllers in its primary tower.

Air traffic controllers, as essential workers, are required to work during a shutdown, but are now doing so without pay.

Joining me now to break this all down is our aviation correspondent, Miles O'Brien.

So Miles, help us understand this ripple effect we're seeing now,

from government shutdown through to the thousands of flight delays we're seeing.

Amna, I think we're seeing so many ripples because the pond is a little bit shallow.

The FAA is short, 3,000 certified controllers.

And so it doesn't take a lot of sick individuals to have a consequence on the scheduling.

The union, which represents the air traffic controllers, says there's

no purposeful campaign here to... These are individuals that have been working under great

stress as the system has been short-staffed for so long. We've been documenting all kinds

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