The Atlanta-based airline blamed the huge loss on a drop in U.S. airfares, soaring jet fuel costs and Florida hurricanes that laid waste to flight schedules.

Delta, which operates its third-largest hub at Salt Lake City International Airport, in September unveiled a turnaround plan that includes dismantling its hub at Dallas/Ft. Worth International Airport and shifting dozens of flights to Salt Lake City and its second-largest hub in Cincinnati. The plan will take effect at the end of January.

But the next several weeks are crucial for the airline - which has lost $5.5 billion in the past three years - in its effort to avoid Chapter 11 bankruptcy.

Negotiations are continuing with pilots over the company's demand for $1 billion in annual wage and benefit concessions. The company also has offered $680 million in bonds to the owners of $2.6 billion of its debt. If accepted, the deals would cut the airline's costs by $5 billion over the next two years.

Delta has made it clear that without pilot concessions and relief from its creditors, it will seek bankruptcy protection.

"As Delta's financial situation continues to deteriorate, time is of the essence," Delta Chief Executive Gerald Grinstein said in a statement.

The Air Line Pilots Association issued a statement Wednesday saying, "Any pilot agreement must be part of a comprehensive restructuring involving all Delta stakeholders. The pilots are also seeking equity in return for their substantial investment."

Airline analyst Ray Neidl of Calyon Securities argues against a growing assumption that bankruptcy is inevitable for Delta.

"There is still time to fix it - if they get all the parties to agree to terms," Neidl said. An agreement with the pilots should come in a matter of two weeks, he said, but creditor negotiations "may drag on until Thanksgiving or December."

In 2003, American Airlines came within 30 minutes of filing bankruptcy, when its union agreed to $1.8 billion in concessions.

But pilot pay, which accounts for less than 15 percent of total operating costs, is only a part of Delta's problem.

Air fares, on average, fell nearly 5 percent for the quarter ended Sept. 30 compared with the same period last year, mainly as a result of intense competition from low-fare airlines. And Delta's operating costs lurched upward as jet fuel prices increased 63 percent to $786 million during the quarter. Finally, the airline calculates it lost $50 million in the four hurricanes that ripped through Florida in September.

Even if Delta can get concessions it needs to put its turnaround plan in place, the future is still cloudy for it and other so-called legacy airlines. Many analysts fear that the industry will never return to its pre-Sept. 11, 2001, level of normalcy. But no one is sure what the new market will look like.

"It's hard to figure out what the successful business model is for the major airlines," said Ralph Mabey, a Salt Lake bankruptcy lawyer and former U.S. Bankruptcy Court judge. "That's been the problem for US Airways and United. It's hard to know what your cost structure has to be to compete."

Neidl believes the evolving market will not sustain as many major airlines - perhaps only two or three.

"We have too many legacy carriers and hubs. All of them are trying to be one of the ones that survive," Neidl said.

Delta's shares fell 6 cents, or 2.01 percent, to $2.93 in New York Stock Exchange trading. The airline's stock has declined 75 percent this year.

Also on Wednesday, legacy carriers American and Northwest airlines, which with Delta make three of the four largest U.S. airlines, posted third-quarter losses driven in a large degree by the 51 percent to 63 percent jump in fuel costs.

l American, the world's largest carrier, had a net loss of $214 million, or $1.33 a share.

l Northwest reported a loss of $38 million, or 54 cents a share.

Continental Airlines Inc., the fifth-largest U.S. carrier, has already forecast a ''significant loss'' for this year and 2005. Continental had a third-quarter loss of $13 million.

United Airlines, the world's second-largest carrier, and US Airways already are operating under bankruptcy protection.