Eric Hamilton

In an interview on the Fox Business Channel, Secretary Duffy said there's been a noticeable uptick in the number of air traffic controllers calling out sick.

Duffy said it's a small fraction of controllers who are creating a massive disruption and suggested the government could fire those, quote, problem children.

Nearly 11,000 certified air traffic controllers are required to work during the government shutdown, but don't get paid until it ends.

Thousands of flights have been delayed this week as the Federal Aviation Administration limits the number of planes in the air in order to keep the skies safe.

Joel Rose, NPR News, Washington.