Space Exploration Technologies is building a rocket with twice the lift capacity of NASA's space shuttle that will also cut launch costs, the company's chief executive said on Tuesday.

The new booster, called Falcon Heavy, is based on the company's Falcon 9 rocket, which has made two successful flights and which NASA has purchased to fly cargo to the International Space Station after the shuttle program ends this summer.

A test flight of Falcon Heavy is planned for 2013 from Vandenberg Air Force Base in California, Elon Musk told reporters in a news conference broadcast over the Internet.

Falcon Heavy can put about 117,000 pounds (53,071 kg) into orbit, twice the shuttle's 50,000-pound (22,680-kg) lift capability.

Flights also would take place from the company's launch complex at Cape Canaveral Air Force Station in Florida, and possibly from nearby Kennedy Space Center, which is soliciting proposals from companies and agencies interested in taking over the space shuttle's launch pads.

The shuttle program is ending after two more flights because of high costs and to free up funds to develop rockets that can travel beyond the space station's 220-mile (354-km) high orbit.

With a price tag of about $100 million per launch, Falcon Heavy is about half the price of existing heavy-lift U.S. rockets built by Boeing Co (BA.N) and Lockheed Martin Corp (LMT.N).

"I think we can realistically start to contemplate missions like a Mars sample return, which requires a tremendous amount of lift capability because you have to send a lander to Mars that still has enough propellant to return to Earth," Musk said. "If you try to do a mission like that with a smaller vehicle, you have to have several launches and either do orbital rendezvous or do some sort of much more complex mission."

Currently, it costs about $10,000 per pound to reach orbit. Falcon Heavy would cut that price to about $1,000 per pound, Musk said.

"We're very, very confident of being able to maintain those prices," said Musk, co-founder of PayPal and chairman and chief executive of electric car maker Tesla Motors.

Falcon Heavy, like Falcon 9, has been designed to meet NASA's requirements for human space vehicles, Musk said.

He said the company, based in Hawthorne, California, was ramping up for mass production of its proprietary Merlin engine, which powers the Falcon rocket family.