Virgin Galactic founder Richard Branson and pilot Kelly Latimer stand next to the 747-400 airplace that would be used to air launch the company's rocket. (Photo courtesy of Virgin Galactic.)

SAN ANTONIO--Richard Branson’s Virgin Galactic is best known for its ambitions to fly tourists to the edge of space. But it has been increasingly focused on another venture: launching small satellites.

The company took another step in that direction Thursday, showing off a new "mothership" aircraft that would help launch its LauncherOne rocket to space. At a hangar at the airport here, Branson showed off the Boeing 747-400 airplane, dubbed “Cosmic Girl,” that would carry LauncherOne into the sky.

Unlike rockets that take off vertically from launch pads, Virgin plans to tether its rocket to the wing of the 747, which would fly to an altitude of about 35,000 feet.

Once aloft, the rocket would drop, fire its engine and shoot off into orbit, where it would deposit satellites.

“I never even thought of satellites when we thought of Virgin Galactic originally,” Branson said in an interview. “I just thought of human space travel and a personal desire to go to space and trying to make dreams come true and so on. And then embarking on that, suddenly you realize there’s another whole aspect to this. Which is equally as exciting, really.”

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He said he wants to help deploy legions of small satellites into orbit that would help provide the Internet and communications services to rural parts of the world that aren’t yet connected.

“I spend a lot of time in Africa and poorer parts of the world, and you know if somebody doesn’t have WiFi or a mobile phone or the Internet they are going to be held back from every body else,” he said. “The satellites will make a massive difference here on Earth.”

Virgin already has signed a $4.7 million contract with NASA to launch more than a dozen experimental satellites on a test flight. And it also has a deal with OneWeb, which plans to build a global Internet satellite system, for 39 satellites with an option for 100 more.

By using a commercial airplane, the company says it can be more flexible and timely because it doesn’t have to adhere to the constraints and schedule of a launch pad.

“You need to be able to send a plane up with 24 hours notice,” Branson said in remarks at the unveiling ceremony. “If you’re waiting for one of these giant rockets to put small satellites into space, you sometimes have to wait six months, or a year.”

The “air launch” is also how Virgin flies SpaceShipTwo, the spacecraft designed to take tourists to the boundary of space. Last year, the craft crashed during a test flight in the Mojave desert, killing one of the pilots.

Company officials said Thursday that the development of the new spacecraft, yet unnamed, was making progress, and that Virgin would unveil it in February before beginning its testing program.

The new 747 would free up the aircraft that flies SpaceShipTwo, known as WhiteKnight, to remain dedicated to the human flight program.

Traditionally, satellites were massive and expensive. But there has been a movement to build smaller, cheaper satellites, some the size of a shoe box, that could be used for communications and observing the Earth.

In September, Virgin announced that it was enhancing LauncherOne so that it would be able to handle larger payloads, including as much as 400 kilograms to low Earth orbit. That would allow the company to compete for more government satellite launch contracts.

George Whitesides, Virgin’s chief executive, said that because the small satellite market has grown so rapidly, the company is treating it on par with its human spaceflight program.

“We view this as an equal business focus for the company now,” he said.

The 747 was plucked from the inventory of Virgin Atlantic, Branson’s commercial airline company. It’s 14 years old and once flew from London, to New York  and to San Francisco.

The aircraft needs to be modified to carry the rocket, which weighs 55,000 pounds. Then test flights would begin in 2017.