United parent UAL Corp. reported its most profitable quarter in seven years Tuesday, a $274 million second-quarter profit that reflected increased capacity on international routes as well as fuller U.S. flights and lower costs. Besides having Hawai'i flights in its operations, the air carrier also owns a minority interest in Honolulu-based Aloha Airlines.

JetBlue Airways Corp. also posted solid second-quarter earnings, but its 50 percent profit increase was tempered by the announcement that it plans to slow its growth in the wake of the February ice-storm debacle.

The better-than-expected earnings by UAL, for years an industry laggard financially, reinforced that carriers are benefiting more than in past years from the busy summer travel season. Like United, many have restructured to reduce domestic flights and trim costs.

Among other U.S. carriers in the latest quarter, American Airlines parent AMR Corp. posted a $317 million profit last week, Delta Air Lines Inc. earned $1.77 billion or $274 million excluding bankruptcy-related items, Southwest Airlines Co. netted $278 million and Continental Airlines Inc. earned $228 million.

Chicago-based UAL had its best quarter since earning $408 million in the second quarter of 2000, before it spiraled into a lengthy decline that landed it in bankruptcy from 2002-06.

The results easily topped Wall Street estimates and more than doubled the company's earnings from a year ago, when it finished in the black for the first time since 2000. Its stock surged.

United has prospered in part by cutting domestic capacity earlier this year, which has meant existing flights are carryng more passengers. It filled 89.1 percent of its seats last month, the highest ever for June.

It also is increasingly focusing on its more profitable international network, including rolling out a revamped international business class cabin this week featuring cushier seats that recline flat and allow long-haul business travelers to sleep lying down.

International passenger revenue climbed 16 percent in the quarter while North American revenue fell 2 percent, for an overall increase of more than 4 percent despite flat capacity growth.

United registered improvement to its operating costs, which have been among the highest of any U.S. airline for years. Costs per average seat mile, excluding fuel and severance charges, declined 0.5 percent from the second quarter of 2006 and operating expenses were reduced by $177 million.

Chairman and CEO Glenn Tilton said the results showed solid performance momentum across the board.

"We delivered these results by maintaining good cost control, executing excellent revenue and capacity management and reducing interest expense by paying down and refinancing our debt," he said in a message to employees.

UAL's net income for the April-through-June period amounted to $1.83 per share, up from $119 million, or 93 cents per share, in the same period a year earlier. That far exceeded the consensus estimate of $1.39 per share by analysts surveyed by Thomson Financial.

Revenue rose 2 percent to a record $5.21 billion from $5.11 billion. Revenue per average seat mile, a commonly used gauge of an airline's health, also climbed 2 percent.

Goldman Sachs analyst Robert Barry hailed UAL for good cost management despite domestic results that are lagging along with those of other airlines.

UAL, which has gradually improved its financial situation since ending a three-year bankruptcy overhaul early last year, also increased its cash balance in the quarter by $895 million to $5.1 billion. The hefty stash of cash has prompted speculation that the company may initiate a stock buyback or add to its fleet in the near future.

With the cash pile mounting, "shareholder pressure for value-added transactions or financial engineering are growing too loud for management to ignore," J.P. Morgan analyst Jamie Baker said in a note to investors.

But Tilton wouldn't tip his hand on the company's intentions.

"We continue to have discussions with the management team and the board on the various best uses for our free cash flow. We haven't made any judgment" on a possible stock buyback, he said on a conference call. "We are managing this business to maximize value for our shareholders."

JetBlue, a low-cost carrier that had been expanding rapidly, increased revenue by 19 percent but missed Wall Street's estimate by a penny a share.

The Forest Hills, N.Y.-based company said net income grew to $21 million, or 11 cents a share, in the second quarter, from $14 million, or 8 cents a share. Revenue rose to $730 million from $612 million a year earlier.

JetBlue said it will take delivery of three fewer airplanes this year and will sell three planes from its fleet. New CEO Dave Barger has said he thinks JetBlue's February storm meltdown was caused, in part, by the fact that the company grew too fast.

"Slowing capacity growth will allow us to strengthen our balance sheet and facilitate earnings growth," Barger said.

But slower growth doesn't mean no growth. JetBlue will continue entering 2 to 4 cities a year, he said.