KNOXVILLE, Tenn. (WVLT) -- Even into early Thursday evening there were still flight delays into and out of Knoxville's McGhee Tyson Airport, nearly 12 hours after an FAA computer glitch in Atlanta caused U.S. airtraffic to come to a halt.

Passengers at McGhee Tyson were relatively understanding, saying dealing with delays is a part of flying.

The computer system was back up and running Thursday morning, but the early slowdown caused a ripple effect all day.

"We can hope the good Lord will give us traveling mercies today," traveler Joyce Wyatt said.

For some delayed travelers, it was only an inconvenience.

"So far, it's only 45 minutes," Anthony Bradley said."Could have been worse. Assuming it doesn't worsen, I'll be able to live with it."

"W would have rather slept," Alex Weaver complains. "We hurried to get up here, and found out it was late anyway."

"I'm going to Canada to take care of my grandchildren," Wyatt said, "while my daughter and her husband go to Germany."

Although the system resolved itself by late morning, it affected many people who were taking connecting flights.

"Once the hubs become backed up, then it kind of has a trickle down effect throughout the day," McGhee Tyson spokesperson Beth Baker says.

The techo-glitch didn't have as much of an impact on non-stop flights. Officials hoped the problem would be fixed by day's end.

"Once I arrive in New Jersey, I have to head over to Long Island, so I can expect about a two hour drive," Bradley says.

You can check your flight by clicking on the link at the bottom of this story.

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ATLANTA (WVLT/CBS) -- According to the Federal Aviation Administration and air traffic controllers, a computer flight system developed a problem at 5:15 a.m. Eastern time Thursday, affecting flight plans electronically, reports CBS News correspondent Nancy Cordes. The computer problem has slowed down air travel across the country with planes at a standstill for one airport.

The system is back online, but McGhee Tyson Airport spokesperson Becky Huckaby says delays through much of the morning and possibly beyond are expected.

"It's going to be hit or miss all day long (for delays and cancellations)," Huckaby says. "There are some flights leaving on time, others delayed by a few minutes, some longer. it really all depends on where you're flying."

The FAA has issued a "ground stop" at Atlanta's Hartsfield-Jackson International Airport, Cordes reports.

A spokesman for AirTran Airways told CBS News that 22 of their flights have been cancelled. The cancellations immediately affect 2,000 people but will have a ripple effect for tens of thousands of passengers. Hartsfield-Jackson serves as a major hub for AirTran's flights, according to the route map on the airline's Web site.

"What airlines are doing is looking at their inventory (and flights) as they get backed up and seeing what they need to do to get back on schedule," Huckaby says.

CBS News correspondent Barry Bagnato reports that some flights are getting in and out of Atlanta. Delta is experiencing “significant delays and cancellations” across the country, not just in Atlanta. There are no indications of when things will return to normal, Bagnato reports.

"We're asking the airlines to be dilligent in updating the boards you see at the airport and online," says Huckaby. "We ask all customers to check our website before they leave how to determine if their flight is delayed."

A link to that website is below this article.

In the meantime, Delta told Bagnato the airline will offer passengers flexible scheduling without charging passengers for changing their reservations.

CBS "Evening News" producer Carter Yang reports that the system, the National Airspiace Data Interchange Network, experienced outages in August 2008 and June 2007. Those outages, Yang reports, were not necessarily as widespread as today's travel disruption.

FAA officials said that radar coverage across the air traffic system and radio communications between the air and the ground are still functioning, so the computer problem is not a safety issue, Yang reports. The FAA is investigating the cause of the problem.

The FAA originally said the computer problem began around 6 a.m. Thursday morning but later said the problem started at 5:15 a.m.

This system is located in Atlanta and generates the flight plans for all flights on the East Coast. The backup system is in Salt Lake City. Controllers in the congested New York area are putting about 20 miles between planes in the air instead of the typical 8 miles, to create extra safety buffers, Cordes reports.

The practical ramifications of this problem are that the entire air traffic control system on the East Coast is slowed to about 40-50 percent of what a normal day would look like. Controllers must input flight data for each takeoff and landing manually.

Bad weather in the Northeast is not helping. And as time goes on and more flights are scheduled in the Midwest and West this will create a ripple effect throughout the system.

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