America's largest airlines are on course to deliver another disastrous year. Goldman Sachs expects the airline industry to lose at least $6 billion in 2002 -- exceeding last year's record losses -- and hit turbulence in 2003 as well. The research firm lowered earnings estimates for airlines across the board Thursday, two weeks ahead of the one-year anniversary of last year's terrorist attacks. Glenn Engel, an analyst at Goldman Sachs, described low autumn bookings as particularly worrisome. "We cannot determine whether the weak bookings reflect a downturn in leisure demand or caution ahead of the 9/11 anniversary," Engel wrote Thursday. "Demand weakness cuts across all airlines, weak and strong, big or small, hub or point-to-point." Despite that warning, Engel expressed optimism about two major airlines. He rates Continental ( CAL) as a buy and recommends Delta ( DAL) as well. "We believe these airlines have the financial staying power, network strength and cost structure to return to profitability faster than their hub competitors," he explained. But some industry experts see little reason for hope. "I don't even see a light at the end of the tunnel until well into 2003 -- maybe later," said Tom Parsons, chief executive of Bestfares.com. "The major airlines have a hard, hard road ahead of them." Michael Boyd, president of an airline consulting company in Colorado, said the airlines are largely responsible for their own problems. Unlike Southwest ( LUV), which prides itself on customer satisfaction, the major carriers have done more than their share to scare customers away, he said. "I don't think this can be blamed on a fear of terrorism," Boyd said. "I think it's an absolute fear of what people have to go through at airports. "Unfortunately, it's only going to get worse as we go forward." John Pincavage, an industry consultant who spent years as an airline analyst, has already predicted wholesale bankruptcies among the major carriers. He compared the airlines to the railroads of the Depression, when virtually all of the major players were forced into the equivalent of Chapter 11 bankruptcy. "There is a precedent for this," Pincavage said. "The big airlines -- all of them -- may have to go through bankruptcy before they can be profitable." Experts are widely expecting UAL ( UAL) to become the first major carrier to follow US Airways ( UAWGQ) into bankruptcy court. ( TSC examined US Airways' woes earlier.) UAL's United unit already warned earlier this month that bankruptcy is unavoidable without major concessions from its labor unions, which it has yet to gain. UAL's stock fell 6.4%, to $3.07, in Thursday afternoon trading. Except for Northwest ( NWAC) -- which slipped back into the single digits Thursday -- the other major airlines were tacking on gains. Leading the sector was industry giant American, up 4.7%, to $10.46 by midafternoon. Delta, one of Goldman Sachs' picks, climbed 2.9%, to $18.22. Continental, the other pick, added 7 cents to hit $10.32.