(AP) - An electronic communication failure Tuesday at aFederal Aviation Administration facility that processes flightplans for the eastern half of the U.S. caused mass delays aroundthe country. The Northeast was hardest hit.

But by early evening, the FAA said that the situation around thecountry was returning to normal, with delays remaining in Atlantaand Chicago.

At one point, an FAA Web site that tracks airport status showeddelays at some three dozen major airports across the country. Thesite advised passengers to "check your departure airport to see ifyour flight may be affected."

The FAA said the glitch appeared to have involved a softwareproblem at the Georgia facility.

FAA spokeswoman Kathleen Bergen in Atlanta said there were nosafety issues and officials were still able to speak to pilots onplanes on the ground and in the air.

She said she did not know exactly how many flights wereaffected, but she said it was in the hundreds. The FAA did notexpect to have total figures until Wednesday. Bergen said that in a24-hour period the FAA processes more than 300,000 flight plans inthe U.S.

Bergen said the problem that occurred Tuesday afternoon involvedan FAA facility in Hampton, Ga., south of Atlanta, that processesflight plans. She said there was a failure in a communication linkthat transmits the data to a similar facility in Salt Lake City.

As a result, the Salt Lake City facility was having to processthose flight plans, causing delays in planes taking off. She saidthe delays were primarily affecting departing flights. FAAspokeswoman Diane Spitaliere said there were some problems witharriving flights as well.

During an early evening conference call with reporters,Spitaliere said Tuesday's glitch appeared to be a software problemand the situation was returning to normal, though the Hamptonfacility was not yet processing flight plans again.

"We have our engineers looking at it and we're doing a completeinvestigation," she said.

She said delays of 30 minutes remained at airports in Chicagowhile delays of 60 minutes remained in Atlanta, which was alsoexperiencing weather issues.

Bergen said there was an unrelated hardware problem at theHampton facility on Aug. 21 that resulted in issues processingflight plans. The FAA says on its Web site that a glitch that dayinvolving the Hampton facility delayed the departure of at least134 flights.

A spokesman for Hartsfield-Jackson Atlanta InternationalAirport, the world's busiest airport, did not immediately return acall seeking comment on the impact there from Tuesday's episode.Bergen said officials at the Atlanta airport were entering flightdata manually to try to speed things up.

Discount carrier AirTran Airways, which has its hub at theAtlanta airport, said in a statement that because of the suburbanFAA center snafu it was at one point taking up to an hour for theFAA to get clearances to the towers for departures Tuesday. DeltaAir Lines Inc., which has its main hub in Atlanta, said flightswere processing for takeoff, but slowly.

The communication failure caused delays for departures andarrivals at Baltimore-Washington International Thurgood MarshallAirport, according to airport spokeswoman Cheryl Stewart. However,she did not have a number on delays.

The FAA at one point asked that no new flight plans be filed,Stewart said.

Phil Orlandella, a spokesman for Massport, which operatesBoston's Logan International Airport, said there were significantdelays there, but it was easing up by early evening.

Carolyn Fennell, spokeswoman for the Orlando InternationalAirport, said 13 Southwest Airlines flights had been affected bythe glitch.

The National Airspace Data Interchange Network is a datacommunications system for air traffic controllers. It's used todistribute flight plans and allows controllers to know when planesare leaving, where they're going and other details.

Allen Kenitzer, a western regional spokesman for the FAA, saidthe Utah system could handle the extra load while workers tried toget the Atlanta area system back online, but it was expected toslow down air traffic.

"We're not going to let an unsafe condition exist. It's justgoing to be slower," Kenitzer said.