Air travelers should brace for disruptions as federal staffing shortages force a 10% reduction in flights across 40 major U.S. airports, a move officials and experts say is necessary to preserve safety. This will affect millions in the weeks ahead.

The cuts, announced by the Department of Transportation this week, stem from chronic shortages among air traffic controllers made worse by the ongoing government shutdown. Airlines have been directed to reduce the number of flights operating through the nation’s busiest airports, which could include New York, Chicago, Miami, Atlanta, and Los Angeles, with a ripple effect throughout the country.

“This has really brought it all to a head where it’s now no longer possible for the U.S. airspace to handle the volume that it had been,” said Hayley Berg, lead economist at Hopper, a travel booking platform. “Seeing a 10% cut on the 40 largest airports, my initial reaction is this is going to impact millions of travelers, and it’s unfortunate, but if it’s what needs to be done for the safety of travelers.”

Unlike weather delays or short-term crew shortages, these cuts are expected to last until staffing is restored — a timeline that remains unclear.

The situation is also unusual for its scale and duration, said Ahmed Abdelghany, associate dean for research at the David B. O’Maley College of Business in Embry-Riddle Aeronautical University.

“The uniqueness of this situation is two things," Abdelghany said. "Number one, it is extending over multiple days … we don’t know when it’s going to end. And number two, it is broad across 40 airports, not just one region. This is what makes it difficult for airlines.”

How airlines decide what to cut

Airlines will not simply cancel 10% of flights at random. They will likely target routes based on revenue, passenger rebooking options, and aircraft and crew routing, Abdelghany explained.

When possible, carriers may cancel an entire round-trip loop — for example, both Orlando-to-Denver and Denver-to-Orlando — so that an aircraft and crew end up in the correct place to continue later flights. This prevents planes and workers from being stranded in the wrong city, which can trigger cascading disruptions across the network.

“Airlines that have more of these round-trip loops in their schedule are in a better situation handling cancellations,” Abdelghany said. “Canceling the round trip does not strand aircraft or crew — it just keeps them on the ground until needed later.”

Routes with higher daily frequency are also more likely to see cuts, since passengers can more easily be rebooked on later departures. Conversely, once-a-day routes could be protected if they are revenue strong, but not necessarily disregarded because they are small or large.

How do I know if my flight is canceled?

Travelers should expect a rise in advance cancellations, not only same-day surprises.

Berg advised travelers to download their airline’s app and turn on push notifications.

“Sign up for text message notifications," she said. "A couple of days before your flight, just check in. Make sure there haven’t been any changes that haven’t been communicated yet.”

Many airlines now include a “Where’s My Plane?” tracking tool, which can help passengers understand whether a delay is likely. It's also important to recognize that this isn't the airlines' making and they are following instructions for the sake of safety for all passengers.

Travelers booking last-minute Thanksgiving flights should avoid the Sunday after the holiday, historically the busiest travel day of the year.

“The airport on Sunday is going to be absolutely crowded everywhere in the United States,” Berg said.

This article originally appeared on USA TODAY: Why airlines won't just cancel flights at random, how to check yours

Reporting by Josh Rivera, USA TODAY / USA TODAY

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