Travelers flying in and out of Philadelphia International Airport could soon face fewer options — and possible cancellations — as the Federal Aviation Administration orders a 10% reduction in flights in some areas beginning Friday.

The agency says the cut will apply to 40 high-volume U.S. markets, a move FAA Administrator Bryan Bedford called a "radical reduction" designed to ease pressure on overworked air-traffic controllers who have gone more than a month without pay during the ongoing government shutdown.

Philadelphia International is on the list of sites that could be affected, along with airports in Atlanta, Dallas, New York City and Los Angeles, a source told CBS News. However, that is not a final list, and the FAA has not yet issued the formal order.

"We have decided that a 10% reduction in scheduled capacity would be appropriate to again, continue to take the pressure off our controllers," Bedford said. "As we continue to see staffing triggers, there will be additional measures that will be taken in those specific markets."

At Philadelphia International Airport, spokesperson Heather Redfern told CBS News Philadelphia the airport has no information yet on how the reduction will affect flights and referred questions to the FAA and the U.S. Department of Transportation.

A spokesperson said Thursday travelers should contact their airline and register for text and email alerts to receive the latest flight status information. 

The FAA directs more than 44,000 flights daily, meaning thousands of trips could be delayed or canceled once the reduction takes effect. Bedford said officials are trying to be "prescriptive and surgical," placing relief where it will "do the most good."

U.S. Transportation Secretary Sean Duffy said the move is meant to prevent a crisis.

"We are going to proactively make decisions to keep the airspace safe," Duffy said.

At Philadelphia International, seven flights scheduled for Friday have already been canceled, along with hundreds around the country.

American Airlines, the largest carrier at PHL, said most of its flights are not going to be affected. If your flight is canceled or you choose not to fly, the airline is letting passengers change their flights for free or request a refund without penalty.   

Workers going without paychecks

For Lane Conley, an airway transportation system specialist, the government shutdown has been difficult.

Conley is a representative for the Professional Aviation Safety Specialists union at PHL, whose members have been working through the shutdown without pay. On Thursday morning, Conley was picketing, holding a sign that read "don't gamble with aviation safety."

He was picketing during his time off the clock — alone, since the rest of his members were busy working.

"A lot of my members come to me, they're asking me the ethics about what they can do to get a second job and where," Conley said. "Even myself and some of my members, we have dual-income households, and we're still struggling with our payments. We've missed one full paycheck. We've got part of another paycheck. We're about to miss our second in two Tuesdays from now."

For frequent travelers like Joanne Zeiger, who flies weekly between Philadelphia and Charlotte to care for her daughter with brain cancer, the delays are already stressful. Last week, she says one of her flights was delayed for hours. 

"The pilot said thank you all for your patience, but we do not have the air traffic controllers in Philadelphia to get you all in on time," Zeiger said. "Talk about stress."

Another frequent flyer, Michael Fineman, said he's concerned about making it home in time to see his family.

"I'd love to see my kids and my wife," he said. "I'd be in big trouble if I don't make it home on Friday."

FAA officials said they would meet with airline executives Wednesday evening to coordinate implementation.

Zeiger, like many travelers caught in the middle, had a blunt message for lawmakers:

"Stop thinking about yourselves," Zeiger said. "Take a look in the mirror, and get your acts together. Because we are sick of this."

Airport shares recommendations 

In a post on Facebook, Philadelphia International Airport recommended travelers arrive two hours early for domestic flights and three hours before international flights and shared this TSA schedule: 

• Terminal A-East: 4:15 a.m. - 8:15 p.m., with TSA Precheck from 4:15 a.m. to 5 p.m.
• Terminal B: 3:30 a.m. - 9:15 p.m.
• Terminal C: 4:15 a.m. - 8 p.m. (TSA Precheck Only)
• Terminal D/E: 3:30 a.m. - 11:30 p.m., with TSA Precheck from 3:45 a.m. - 8 p.m.

The airport also shared these changes related to TSA checkpoints: 

• Terminal A-West travelers can use the A-East checkpoint (just a four-minute walk).
• Terminal A-West ticketing and bag check remain open.
• Terminal F travelers can use the D/E checkpoint (about a three-minute walk).
• Terminal F ticketing and bag check remain open.