CLEVELAND, Ohio -- United Airlines' promise to stay in Cleveland expires today, but that doesn't mean anything will change.

Two years ago, after merging with Continental Airlines, United Continental Holdings Inc. signed an agreement to keep its huband 90 percent of its flights at Cleveland Hopkins International Airport.

After two years, the world's largest airline was free to change its mind about keeping Cleveland as its 10th service hub.

But from all accounts, nobody expects anything like that to happen today - or in the near future.

"United is proud to call Cleveland a hub and serve the city's business and leisure travelers," said United spokesman Joe Micucci in Chicago.

"We continue our partnership with local business and community leaders to provide viable and sustainable air service for Cleveland."

Not only is the region's largest carrier not showing any signs of leaving, United has actually expanded its nonstop flights out of Cleveland Hopkins:

* United added 10 daily nonstops this summer: one daily flight each to Boston, Denver, Dallas-Fort Worth, Washington Dulles, Portland (Maine), San Francisco, and St. Louis, Mo.; and three more daily flights to Chicago O'Hare International Airport.

* On Dec. 19, United will introduce two daily nonstops to Nashville.

* Starting Feb. 14, United will start flying nonstop to Oklahoma City.

That doesn't mean, however, that United for the Hub and other regional efforts to drum up support for the airline will diminish.

Joe Roman, president and chief executive of the Greater Cleveland Partnership, said the message has changed from "Keeping the Hub" to "Growing the Hub," and increasing awareness of its importance to the business community.

And even the most fervent United supporters acknowledge that there remains a gap between what business travelers see in the hub and what leisure passengers think of United.

With United's nearly 250 daily departures from Cleveland, the Greater Cleveland Partnership estimates the hub's economic impact at more than $4 billion, which includes its role in attracting business, travel and tourism and conventions and corporate meetings.

The number of United and United Express flights out of Cleveland varies according to the time of year, but it's still the airport's largest carrier with 65 percent of the flights, spokeswoman Jacqueline Mayo said.

"While we cannot speak for United, we can say the hub will remain as long as it is a productive asset for United and Northeast Ohio travelers use the service," Airport Director Ricky Smith said in an emailed statement.

"We're pleased to say that based upon United's new service announcements for flights from CLE to Nashville and Oklahoma City, that they still genuinely value their Cleveland hub and its performance."

Rob Turk, executive vice president for Professional Travel Inc. in North Olmsted, which manages travel arrangements for more than 300 companies and organizations, said: "The Northeast Ohio companies that we work with fully support and see the value in having a hub carrier in Cleveland.

"We're optimistic, and we think United is still committed to the Cleveland hub."

Even though other airlines might offer lower airfare to some cities, the long-term benefits of keeping the hub outweigh the fare difference, Turk said.

"We've seen a double-digit increase in overall support of the hub carrier," with more than half of their clients choosing to fly United.

David LaRue, president and chief executive of Forest City Enterprises Inc., said: "I can't overstate the importance the hub has for us.

"Since we are a national real estate company, being able to get from Cleveland to multiple markets that they service directly -- like Boston, New York, Washington, D.C., Denver, Los Angeles, San Francisco and Dallas -- is a huge benefit just in terms of efficiency," he said. "Those are the core markets where we do business."

Of the estimated 2,600 flights that Forest City employees take in a year, more than 75 percent of those flights are on United Airlines, spokesman Jeff Linton said.

LaRue compared the risk of losing United from Hopkins to the prospect of a major anchor tenant whose lease is ending at a shopping center.

"If you lose that major tenant, it affects the value of the entire property," so you concentrate your efforts on preventing it from leaving, he said.

David Gilbert, president of Positively Cleveland, the region's convention and visitors bureau, said that despite the community's best efforts, "Ultimately, United's decision on the hub is a financial one; 'Is it profitable?' and 'Does it fit into their business plan?'

"It's not a matter of 'Do they like Cleveland or not?' "

"We've heard anecdotally that the hub is performing well, and we're getting more people to fly United" and understand the importance of maintaining the hub.

Last week, United Continental Holdings reported that its passenger revenue per available seat mile -- an important measure for airlines -- dropped by an estimated 1 percent to 2 percent for the third quarter.

United, liked other airlines, has cut capacity by 1.4 percent on United and United Express flights, but the news raised concerns about passenger demand and still-high fuel costs.

United does not break out its financial results by market.

But Greater Cleveland also is becoming more of a business and tourist destination, drawing 14.9 million visitors from outside a 50-mile radius in 2011, compared with 13 million in 2009.

The number of hotel rooms is up 10 percent this year compared with this time last year, and both of those numbers are expected to jump even higher when the medical mart and convention center open next year.

"We're encouraging locals who are involved in regional or national associations or who are in positions of influence to help us bring that meeting or convention to Cleveland," Gibert said.

"We're reaching out to both CEOs and meeting planners within mid- to larger corporations in Cleveland to make sure that they're aware of what Positively Cleveland can do to help them plan and manage those meetings at no cost, and we're already seeing the fruits of that labor."

Lee Thomas, managing partner of the Cleveland office of Ernst & Young, which provides professional audit, tax, transaction and advisory services, said that taking advantage of United's nonstop flights enables his 1,200 local employees to maximize their time advising out-of-town clients and still get home to their families.

Although Ernst & Young doesn't officially specify that United is its first choice airline, he said that more often than not, it ends up being the best option simply because it has the most direct flights.

"Are we willing to pay a premium for having a hub here and having those direct flights?" he said.

"If it costs a couple extra hundred bucks and we can save someone five hours, six hours or seven hours by flying direct instead if having a layover, then we think it's worth it."

Bill Christopher, chairman of the Greater Cleveland Partnership's Air Service Demand Task Force, pointed out that Columbus, Cincinnati and Pittsburgh each lost their hubs, and "nobody who's ever lost one has gotten it back."

Even though United's traffic and revenue numbers still aren't as high as everyone wants them to be, "we know a lot of cities who'd love to be in our position," he said.

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