BEVERLY HILLS, Calif. — Entrepreneurs of the new commercial space age plan to start test flights in 2010 of a practical four-engine rocket ship that will take people on Mach 2 thrill rides up to 200,000 feet and which also has the interest of the Air Force.

The design of the Lynx rocket was shown off last week by Xcor Aerospace, a Mojave, Calif.-based company that has spent nine years developing rocket engines.

Fueled by liquid oxygen and kerosene, the two-seat ship — a bit more slender than a small executive jet — is intended to operate like an airliner, making up to four flights a day while using runways for takeoffs and landings like a normal airplane.

CEO Jeff Greason withheld specifics of costs and technical details at a news conference but said he was certain investors will finance construction of the Lynx, which he estimated will cost "south of $10 million," not including previous development costs.

Xcor has been in talks with companies that may operate Lynx spacecraft for space tourism, Greason said without naming them.

"We don't usually discuss a lot of the details of our projects until the hardware rolls out and that's not so much because of some deep-seated desire to be secret as it is that we don't want to tie the hands of our engineers by saying too much too soon," Greason said.

But he said the decision to talk about the Lynx was primarily due to the involvement of the Air Force, which under a contract has been receiving reports on the progress of Xcor's design work for the past year and recently notified the company it will continue that under a Phase Two contract.

Coming two months after British billionaire Richard Branson's Virgin Galactic unveiled a model of SpaceShipTwo, a six-passenger vehicle that may begin flight tests this year, the Xcor announcement suggested that real competition is nearing in the infant industry of space tourism.

Greason said that since various companies are offering different vehicles that will provide different experiences, "we thought it was time to let the potential travelers know what the options were out there so they can start thinking about what their plans need to be."

Greason wouldn't discuss what Lynx operators might charge for a ride, but he said Xcor's price to operators should allow them to charge passengers half what others charge. The ability to launch four times a day will make up for the fact that the Lynx will only carry one passenger at a time, he said.

The Lynx will have a pressurized cabin but the pilot and passenger will wear helmets and pressure suits for safety. Passengers will need some kind of medical clearance and perhaps a day's training in such things as operating the suits and evacuating the rocket. The Lynx will have an escape capability but no ejection seats.

While SpaceShipTwo will be flown by a crew of two with passengers in seats behind them, Xcor chief test pilot Rick Searfoss, a former space shuttle commander, emphasized that the passenger on each Lynx flight will ride "in the co-pilot position essentially, with an incredible view the whole time."

A Lynx flight will begin with all four rockets firing to send the craft down the runway, said Searfoss, 51. The Lynx will tilt up in near-vertical flight, with increasing acceleration.

Drawing on his shuttle experience, Searfoss likened the G-force feeling to lying on his living room floor with legs sticking up in the air and "having two big dogs sitting on your chest."

Searfoss said that when the engines shut down three minutes into flight, the passenger will instantly feel weightless as the Lynx coasts to the top of its ballistic trajectory.

While a SpaceShipTwo passenger might unbuckle and float briefly, a Lynx passenger will remain strapped in. But Searfoss said the main enjoyment will be the vantage point — "high enough to look out across the horizon and see that thin blue line of the atmosphere, see the blackness above you even though its broad daylight below."

On the way down, the Lynx will go into a long circling glide, landing 30 minutes after takeoff.

Greason was asked whether a flight to 200,000 feet — about 37 miles — is high enough considering that SpaceShipTwo's predecessor, SpaceShipOne, topped 62 miles in three flights in 2004.

"I think it's more than high enough to offer an experience that's going to leave us with more people lining up to take the ride than we'll at first (be) able to supply," Greason said.