Welcome to day one of flight-mageddon. The Federal Aviation Administration is requiring airlines to reduce flights, because of the strain on air traffic controllers amid the longest federal government shutdown ever. 

Fewer flights mean reduced supply just as demand is about to ramp up for the holidays. There are going to be consequences for both airlines and consumers. 

Airlines have a scheduling mess on their hands. And an unprecedented one, said Ahmed Abdelghany, a business professor at Embry-Riddle Aeronautical University. 

“It's multiple airlines, multiple airports,” he said. Unlike, say, a storm or a computer outage, all carriers across the country have to adjust. 

“Eventually airlines will not be able to fly some of their flights, and eventually they have to refund passengers… because passengers will not be able to travel in some markets,” Abdelghany said.

Indications are that airlines are focusing on trimming shorter regional routes first.

Rebecca Hupp, director of Boise Airport in Boise, Idaho, is preparing. 

“Many of the airports that we have connections to are on the list, but our hope would be that people are aware of potential flight changes before they get to the airport,” she said.

Some travelers might opt for ground transportation, or cancel their plans altogether. “It will obviously mean lower revenue for airlines,” Hupp added.

Nawal Taneja, professor emeritus at Ohio State University, is a longtime airline industry advisor. He said airlines may try to make up for that lost business by charging more on other routes where they can. 

“As far as the consumers are concerned, yes, the prices are likely to go up,” he said.

So, pain ahead for both passengers and airlines. How much pain depends on how long the disruptions last.