A resurgent Delta Air Lines has won back some customers from discount rival AirTran Airways, prompting AirTran to cut flights in Atlanta and expand elsewhere.

That's not Delta bragging, it's AirTran explaining the situation to analysts.

"Today, Delta is much stronger than the Delta we saw four or five years ago," AirTran Chief Executive Bob Fornaro said Tuesday at an investment conference in New York. "They've been able to ultimately take back customers that we actually borrowed for a couple of years. They are a tough competitor."

Fornaro said Orlando-based AirTran now has about 200 flights a day at Hartsfield-Jackson International Airport, its largest hub. AirTran had about 260 flights a day at the hub in 2008.

That was probably "too high" for a long-term scenario, Fornaro said during the J.P. Morgan Aviation, Transportation & Defense Conference in New York.

For years, AirTran focused on Atlanta for growth. Atlanta-based Delta struggled after the Sept. 11, 2001 terrorist attacks, then filed for Chapter 11 bankruptcy in 2005. "We were able to gain a lot of leisure and business travel from Delta," which helped AirTran post strong profits in 2007, Fornaro said.

Delta finished its bankruptcy reorganization in 2007, which Fornaro cited as reason for its renewed vigor, and closed a massive merger with Northwest Airlines in 2008.