CHICAGO — United Airlines got a much-needed boost of confidence, as well as $1.2 billion in cash, from credit card partner Chase Bank, sending its shares soaring 69 percent yesterday.

The deal, unveiled during United's midmorning earnings call, appeared to quell investor concerns about the carrier's viability as high oil prices, a sputtering economy and a looming seasonal fall-off in travel threaten to drain airlines' cash.

Analysts think that unless oil prices fall dramatically, mounting financial pressures will send one or more large airlines into bankruptcy over the next year. Those that can amass hefty cash reserves stand the best chance of surviving the tumult.

Chicago-based United appeared vulnerable after recording larger losses than its peers during the first six months of this year. But Chase's decision to purchase about $600 million of its frequent-flier miles far in advance suggests the powerful New York bank, which has deep ties to United, sees the carrier as a survivor.

"The market is assured that United is not going into bankruptcy any time soon," said Roger King, airline analyst with CreditSights Inc.

United CEO Glenn Tilton also provided new details of a partnership with Continental Airlines that could increase United's global reach and of cuts intended to reduce its overhead. United plans to eliminate 7,000 jobs by the end of 2009 and won't hesitate to cut deeper if the market declines, officials said.

Tilton also said United will trim overseas routes by 7 percent in the fourth quarter. He said routes to be eliminated will include Denver-London, Los Angeles-Frankfurt and San Francisco-Nagoya, Japan. Tilton said United will close its Nagoya station.

United ended the second quarter with about $2.9 billion in unrestricted cash, roughly the same as it had at the beginning of the period, even though it has raised $550 million in a series of financings during the period.

United suffered a net loss of $2.73 billion, or $21.47 a diluted share, compared with earnings in the year-ago quarter of $274 million, or $1.83 a share.

However, United's losses were magnified by $2.27 billion in accounting charges to write down "goodwill" on its balance sheet.

Excluding all charges, United lost $151 million — $1.19 per share, far less than the $2.05 deficit that experts had been forecasting.

United was one of three airlines that announced quarterly losses yesterday.

US Airways and JetBlue both posted big losses, though they, like United, beat Wall Street estimates.

For the three months ended June 30, US Airways lost $567 million, or $6.16 per share, compared with a profit of $263 million, or $2.77 per share, for the same period last year. Revenue rose 3 percent to $3.26 billion.

JetBlue posted a loss of $7 million, or 3 cents per share, compared with a year-ago profit of $21 million, or 11 cents per share. Revenue rose by 18 percent, to $859 million, from $730 million a year earlier.

And last week, Atlanta-based Delta Air Lines Inc. reported a $1.04 billion loss for the quarter; and Fort Worth, Texas-based AMR Corp., the parent of American, posted a $1.45 billion loss for the same period. Continental Airlines swung to a $3 million loss.

United's Tilton said the nation's second-largest carrier is already mapping out plans to expand its partnership with Houston-based Continental, billed by some as a "virtual merger," to give passengers far more connections to Latin America, currently the most profitable international region for air travel. In addition, the two carriers plan later this week to formally request antitrust immunity to coordinate North Atlantic flights along with Lufthansa and Air Canada.

Continental plans to join the Star Alliance, which United co-founded with Lufthansa, but can't exit its current alliance until two prominent members, Delta and Northwest Airlines, close their own merger.

"Nothing's going to happen there that's going to make them money anytime soon," King said of United's new venture with Continental, announced in June.

That's where United's ties with Chase come into play, a close relationship that Chase inherited from Bank One Corp., a Chicago-based bank that it acquired in 2004. In addition to processing United's credit card transactions, Chase owns the Mileage Plus affinity card, whose users accrue United frequent flier miles with every purchase.

Yesterday, Chase agreed to restructure one of the terms of an earlier credit card agreement, which has required it to hold $375 million of United's funds in reserve as insurance against United potentially being unable to provide the travel already paid for by credit card.

Under the new agreement, United's holdback has been reduced to $25 million, freeing up $350 million in previously restricted cash.

Once the carrier closes its new agreement with Chase, and including the $600 million of frequent-flier miles, its unrestricted cash will immediately increase by about $1 billion, said United spokeswoman Jean Medina. United also expects the transaction to increase its cash flow by about $200 million in the next two years.

Moreover, United has $3 billion in unencumbered assets that it could use to raise additional capital.

What's unclear is how long it will take United and most other major carriers to right their operations.

United plans to reduce its schedule by up to 11.5 percent in the fourth quarter, year over year, and by as much as 9 percent next year. Many of its competitors are likewise lopping their route networks at an unprecedented scale. It's anybody's guess how events will play out, how consumers will respond.

"It's not as if everything is going to go away," said aviation analyst Robert Mann. "But figuring the winners and losers is a gamble."

The Associated Press contributed to this report.