"This is about where’s the pressure and how do we alleviate the pressure," Transportation Secretary Sean Duffy said.

"Those airports impacted reach far beyond the initial list," Nastro said. "While 40 U.S. airports is a lot, the effects on travelers can reach far beyond just the single airport since almost 70% of all U.S. flights are either to or from any of these airports."

The cancellations would amount to "fewer than 200 flights" on Friday, Nov. 7, before continuing throughout the weekend.

The reductions in airspace capacity will start Friday, the 37th day of the shutdown, and just ahead of the busy Thanksgiving travel period.

Airline planning and scheduling teams went into overdrive to identify which flights to cut while minimizing consequences for customers, pilots, flight attendants and the bottom line.

The Federal Aviation Administration’s looming reductions, set to take effect in less than 24 hours, could have significant impacts on commercial flights in and out of San Francisco International Airport,

Airlines are cutting flights starting Nov. 7. See what each airline has announced for its Indianapolis flights.

The FAA will reduce air traffic at 40 airports beginning Friday. Philadelphia International Airport is among those expecting flight cuts and delays. Talks between Democrats and Republicans to end the shutdown are intensifying,