FORT WORTH — The nation's airlines are about to do something they haven't done in six years: report profits for a second consecutive quarter.

Fort Worth-based American Airlines today will kick off the parade of profit reports for the July-September quarter. If Wall Street has it pegged, airlines are likely to report a collective profit of more than $1 billion for the quarter.

American is expected to report a profit despite costs associated with the Aug. 11 bomb-plot scare in London. The largest U.S. carrier in the U.S.-U.K. market, American said last month that the terrorist scare and its aftermath cost about $50 million in lost revenue.

Two other big Texas-based carriers, Continental in Houston and Southwest in Dallas, are expected to report quarterly profits tomorrow.

The rest of the country's big airlines are expected to report over the next few weeks and to show a profit. The only exceptions will be Delta and Northwest, both of which have been operating in Chapter 11 bankruptcy since September 2005. And even they are expected to report third-quarter operating profits excluding bankruptcy-related costs.

Ray Neidl, airline analyst at Calyon Securities, says he expects the industry's third-quarter profits to total about $1.3 billion, excluding one-time accounting items. For all of 2006, he expects the industry to earn about $1.1 billion, which would be the first industry profit since 2000.

Neidl expects the airlines to report record profits in 2007 of $6.1 billion. His projection assumes continuing economic stability and oil prices at about $60 a barrel.

Last achieved in the second and third quarters of 2000, the latest run of profitability for the industry is driven by general economic strength, high travel demand and higher fares. Third-quarter revenue is expected to be up about 10 percent from the quarter last year.

Airlines' restraint in adding flying capacity and moderating oil prices also are factors. However, the full impact of a 20 percent decline in oil prices since midsummer won't be evident until results of the fourth quarter are announced early next year.

Still, analysts who cover the airlines continue to express concerns about the industry, which has lost more than $40 billion over the last five years.

Matthew Jacob at Majestic Research says he's concerned about recent guidance from most big carriers suggesting slower growth in the average revenue generated from flying one airplane seat one mile.

"We're still talking about pretty solid growth," he says. "Most will be in the mid- to high-single digits."

That's down from the double-digit growth that many carriers were reporting earlier this year.