A Computer Error Lets Travelers Book Rock-Bottom Airfares on Delta Some lucky fliers capitalized on a computer error Thursday to buy inexpensive flights on Delta Air Lines. From about 10 a.m. to noon Eastern, certain Delta fares on the airline's website and other booking sites were showing up incorrectly, offering some savvy bargain hunters incredible deals. A round-trip flight between Cincinnati and Minneapolis for February was being sold for just $25.05 and a round trip between Cincinnati and Salt Lake City for $48.41. The correct price for both of those fares is more than $400. Trebor Banstetter, a spokesman for the Atlanta-based airline, said that the problem had been fixed, but that "Delta will honor any fares purchased at the incorrect price." New Department of Transportation regulations, aimed at truth in advertising, require airlines to honor any mistake in fares offered. Jackie Fanelli, 27, learned about the fares from a friend's Facebook page. She tried to buy a $98 round-trip first-class ticket from her home city, Baltimore, to Honolulu on Priceline.com but the transaction did not process. "It was too good to be true," Ms. Fanelli said. I try to go away every other year and this was not the year. Delta's website was having lingering problems from the increased traffic Thursday afternoon. "People have been bragging about booking six first-class tickets to Hawaii," said George Hobica, founder of Airfarewatchdog.com, which promotes airfare sales. People hate the airlines so much that when this happens, they say: I'm going to get back at you for the time you broke my suitcase and didn't pay for it. Other airlines have faced similar problems. In September, United Airlines experienced an error in filing fares to its computer system. Many customers got tickets for $5 or $10, paying only the cost of the Sept. 11 security fee.