CHICAGO — Airline stocks are soaring as bankruptcy fears for major U.S. airlines appear to be dissipating faster than a jet's vapor trail.

Just a month ago, analysts were mapping the point at which Chicago-based United Airlines and other carriers would run out of cash. But analysts have reversed course in recent days, predicting United and others may actually make money in 2009 if fuel prices continue to tumble.

Others caution investors against getting too giddy over airlines' brightening prospects, warning that oil prices remain highly volatile and haven't yet fallen to the point where profits are assured.

Furthermore, no one knows whether consumers will balk at the rash of new fees that are just starting to take effect at many old-line airlines. Also unknown: how the unprecedented 11 percent combined cutback in domestic service planned by these carriers for this fall will affect their revenues, expenses or pricing.

"There's a lot of risk there," said Michael Derchin, an airline analyst with FTN Midwest Securities.

Jamie Baker, an airline analyst for J.P. Morgan Securities Inc., triggered a rally in United's shares yesterday when he predicted in a research note that it will earn a profit of $2.64 per share in 2009. Baker thinks United's performance will be bolstered by deep cost cuts and the $1.2 billion it will raise through a recent agreement with credit card partner Chase Bank, J.P. Morgan's parent company.

Baker had previously predicted that United would lose $7.12 per share in 2009 after racking up a whopping $11.48 per share deficit this year. In the report, he attributed the turnaround at United and other carriers to a combination of fiscal discipline, new liquidity and moderating fuel expenses.

"There is simply no escaping the fact that the recent jet fuel price decline, now topping $1 (per) gallon from June's peak, represents the single most rapid and significant annualized savings the industry has ever realized — topping $13 billion at current levels," Baker wrote.

United's shares closed yesterday at $13.30, up 8 percent for the day's trading session. The carrier's stock has risen nearly three-fold since bottoming out at $3.13 on July 15. That $10 jump is the largest increase seen by any large U.S. carrier over the past month

But other analysts think it will take longer for airlines to recalibrate operations to offset fuel bills that, even with oil at $113 a barrel, are still 50 percent higher than they were a year ago. There's also significant risk that oil prices will rise to the stratospheric highs seen earlier this summer once the global economy regains steam. The U.S. Department of Energy predicts that prices will be above $130 for much of next year.

Kevin Crissey of UBS Investment Research thinks every large carrier except Southwest will tally large losses next year. In an Aug. 11 research note, he cautioned that airlines would have to struggle to meet the hefty revenue targets projected by analysts, especially given the large capacity cuts many have planned.

Derchin attributes the recent rally to investor relief that none of the major U.S. carriers appears in imminent danger of bankruptcy. Airline stocks have also attracted investors seeking to hedge fuel-related holdings against sudden price drops.

But the industry is far from robust, Derchin cautioned, and will likely remain that way until 2010. "We've gone from the market viewing these companies as short-term bankruptcy risks to more like survivors," he said.