Flights are being cut at 40 of America’s busiest airports to offset air traffic controller shortages in what’s become the longest government shutdown in U.S. history. But it’s not just those travelers who will be affected by the cancellations.

“There's going to be extensive disruption across the entire nation’s air transportation system,” said Henry Harteveldt, and airline industry analyst and president of Atmosphere Research Group, an independent travel analytics firm. And the consequences could last longer than the shutdown.

Here’s what travelers should know as the cancellations begin taking effect Nov. 7.

Flight impacts: 'Connecting passengers are potentially even more at risk'

The Department of Transportation and Federal Aviation Administration directed a 10% reduction in flights at 40 airports.

“It's going to be a step-up, phased-in approach to cutting flights,” Harteveldt said. “It will start Friday with a 4% cut to flights ... and it will step up from there to 10%.”

United Airlines and Delta Air Lines confirmed they are canceling flights ahead of time to avoid same-day congestion at the airports.

“Airlines have to consider the flow of aircraft and crew when they cancel flights. It’s not just canceling one flight — that aircraft and those crew members are supposed to continue later in the day,” Ahmed Abdelghany, associate dean for research at the David B. O’Maley College of Business in Embry-Riddle Aeronautical University, told USA TODAY. “So the airlines that have more round-trip loops in their schedule are in a better position to handle cancellations. If you cancel both flights of the loop, the aircraft and crew end up in the right place later. That avoids stranding planes and crew, which is what makes recovery possible.”

Impacted airports include hubs like Hartsfield-Jackson Atlanta International, Chicago O’Hare International and Los Angeles International, but Shye Gilad, a professor of Practice in Management at Georgetown University’s McDonough School of Business, said travelers at other airports will be impacted, too.

“I think connecting passengers are potentially even more at risk, more likely to experience fare increases, less frequent flights, less options” and potentially much longer layovers than usual, he said, noting that airlines may increase prices to offset lost revenue. Gilad was an airline pilot for 10 years and his specialities include the airline industry.

Airlines are trying to minimize impacts on travelers, but Hartevelt compared the challenge to disassembling Humpty Dumpty without smashing him into 1,000 pieces.

“For an airline to be told by the government they've got 36 or so hours to start dismembering their carefully built flight schedules doesn't give airlines a lot of time,” he said, noting that in addition to crew availability, airlines are juggling gates, maintenance schedules, passenger demand, and more. He said it’s a mixed blessing that demand is relatively low right now, because that means flights were already scaled back compared to summer. “With flights on so many airlines often close to full or completely full, it leaves airlines very little flexibility.”

Even if the shutdown ends, the impact of cuts will last

Airlines may face even less flexibility in the weeks to come.

"We have to remember that this is up to a 10% reduction just based on staffing, but that doesn't mean that other kinds of delays won't happen: weather, mechanical problems,” Gilad said. “Those kinds of interruptions are still going to happen, and when you reduce the capacity ... it's harder to recover. You don't have as many aircraft and employees in the system to recover, so that can be problematic.”

Both he and Hardeveldt warned that some Thanksgiving travel plans could be ruined or at least shifted, depending on how long the cuts continue.

“That could mean more traffic on the highways and perhaps other modes of transport or simply people not being able to travel at all ... and having to opt out of spending time with their families over the holidays,” Gilad said.

If people choose not to travel, Hardeveldt said, “It's going to have a downline impact on not just the airlines and the concessions at the airport who will feel the financial impact, but the destinations that people are traveling to may see fewer visitors.”

That may be avoided if the shutdown ends sooner, but Hopper analyst Hayley Berg noted, “It’s not that the day the shutdown ends, this capacity restriction is lifted. The qualifier is that they’re not going to lift this capacity reduction until air traffic control and FAA are operating at the staffing level ... That might not happen immediately once these employees are paid and have had their time off.”

Abdelghany agrees: “Even if the government reopens, recovery will still take time. Some passengers will have to be refunded and removed from the system because capacity simply cannot absorb everyone. The severity and duration of this reduction will determine how long recovery takes.”

This article originally appeared on USA TODAY: What travelers should expect as airlines cancel flights nationwide

Reporting by Eve Chen, USA TODAY / USA TODAY

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