Mike Boyd, who heads the Boyd Group, an aviation consulting and forecasting company based in Evergreen, Colo., projects a 13.4 percent growth in passenger traffic at McCarran by 2012. Boyd's figures, announced this week at the 11th-annual aviation forecast conference here, says McCarran is expected to enplane 26.2 million passengers a year in six years.

Since most passengers at McCarran are counted twice for their airport usage — once when they arrive and once when they leave — Boyd's projection would mean the Las Vegas airport would serve 52.4 million people.

Airport officials have said McCarran has a capacity of about 53 million passengers, but they're hoping that a new airport proposed south of the city would relieve some of the traffic. But the Ivanpah airport isn't expected to be built and operational until 2017 or 2018.

Clark County Aviation Director Randy Walker already sounded the alarm on capacity issues earlier this year when commenting on growth issues associated with MGM Mirage's Project CityCenter, Boyd Gaming's Echelon Place and an expected project by Harrah's Entertainment.

According to Mike Boyd's forecast, Las Vegas' growth prospects would rank it as the seventh fastest growing hubsite airport in the country behind Detroit, Dallas-Fort Worth, Chicago's Midway Airport, Washington's Dulles International, Philadelphia and Phoenix.

Boyd defines "hubsite airports" as those that have some connecting traffic. Walker says Clark County prefers flights and airlines that deliver passengers to Las Vegas and not those that connect passengers to other cities because of the airport's importance to the city's resorts. Walker often notes that McCarran is the No. 2 operation and destination airport in the country, meaning that it is only behind Los Angeles as an airport for a passenger's end destination.

Also making an appearance in Boyd's forecast of the 25 fastest-growing airports in the country was Reno-Tahoe International Airport, which is projected to have an 18.7 percent growth rate over the next six years, with 3.1 million enplanements projected by 2012. It's ranked 20th in the nation for all markets.

Boyd said the leading growth market is the Sarasota-Bradenton airport in Florida, which is expected to grow by 33.1 percent to 976,000 enplanements by 2012.

Most airport growth nationwide is expected to be driven by community investment, such as new manufacturing and production plants in their respective cities. In the case of Las Vegas and Reno, Boyd said quality-of-life factors are generating most of the community growth. As he said at his conference last year, water development issues are the wild card for the city and its airport sustaining the forecasted growth.

The state's vibrant tourism industry also is a key factor. McCarran had back-to-back months of airport traffic exceeding 4 million passengers in July and August. Gaming revenue exceeded $1 billion in August, the sixth time it has hit that level.

Boyd said the reason traffic is growing nationwide is that several airlines are retiring passenger jets with fewer than 50 seats in favor of larger-capacity single-aisle jets. Boyd also is counting on bumps in international traffic, particularly the Chinese market, to expand passenger counts across the United States.

But he also cautioned that ever-volatile fuel costs, a slowing in the economy and increased competition among low-cost carriers and a resultant pull-back of capacity by those carriers could cloud the growth picture.

Boyd said the low-cost carrier market is getting to be an increasingly hostile competitive environment and that there already are signs that growth is slowing and change is occurring.

Low-cost carriers provide about 71 percent of the seats coming into the Las Vegas market — 78.3 percent if you count United Airlines' Ted service as a low-cost carrier.

Both AirTran and JetBlue have deferred orders on some aircraft and industry stalwart Southwest Airlines has entered two big-city markets, Denver and Washington's Dulles International Airport, to expand market share. Southwest attributes much of its operational success in the past to staking out niches at secondary airports that are cheaper to operate from, such as Midway Airport instead of O'Hare in Chicago and Manchester, N.H., and Providence, R.I., instead of Boston.

Boyd said Southwest, the largest operator at McCarran with more than 1 million passengers a month, may try some additional unconventional approaches in order to bolster market share.

The company already has completed a six-week trial, experimenting with assigned seating. One of Southwest's trademarks is its first-come, first-served approach to seating on flights.

During the test, on some routes flown from San Diego, Southwest determined that there were no conclusive results for the experiment.

John Jamotta, senior director of schedule planning for Southwest, said the airline appears to be headed back to the drawing board when it comes to assigned seating because about as many people disliked Southwest's assigned-seats methods as people who liked them.

Whitney Eichinger, a spokeswoman for Southwest, said additional tests may be forthcoming as the company experiments with other boarding routines.

"In the San Diego tests, sometimes planes were boarded faster than usual, but sometimes they weren't," she said. "There was nothing conclusive."

Eichinger said the company may tinker with some procedures, but the airline is far from reaching a decision about whether to assign seats or keep the current process.

Boyd also predicted Southwest would study operating another aircraft type in addition to the Boeing 737. The airline often touts the operating efficiencies from crew familiarity, to training, to maintaining an inventory of spare parts as the reason it has stuck with the twin-engine 737, Boeing's most utilized aircraft.

Eichinger said Southwest is always looking at options to gain more fuel efficiency in operating their planes, but there have been no plans made to look at other aircraft types.

Boyd suggested that Southwest could have the leverage to work with Boeing to develop a 737 model using composite technology that is being used to construct the Boeing 787 Dreamliner jet, which is expected to be introduced in 2008.