The Dragon capsule, a prototype passenger spaceship developed by Space Exploration Technologies, is set for a practice cargo run to the International Space Station in December. The capsule will carry food, water and other station supplies

According to Bobby Block, SpaceX vice president for communications, the liftoff of the Dragon capsule aboard the SpaceX's Falcon 9 rocket has been targeted for Dec. 19, although the final launch date will be set by NASA.

SpaceX's contract called for three test flights before the company starts delivering cargo to the station under a separate $1.6 billion contract. With Dragon's successful debut mission in December 2010, however, SpaceX petitioned NASA to combine the objectives of the next two flights.

In its trial run to the International Space Station, SpaceX plans to put Dragon into orbit to test its maneuvering, communications and other systems. If successful, the capsule would then be cleared to approach the station and astronauts would use the station's robotic crane to attach it to a berthing port.

Unlike other cargo vessels which incinerate in the atmosphere after leaving the station, Dragon returns via parachute and lands in the ocean bringing cargo from the station as well.

"It's important that we're successful and we're doing a lot of work with our NASA partners to make sure that we've done all the necessary cross checks, verify all the requirements to make sure this vehicle is ready to go," said SpaceX vice president Ken Bowersox at the Symposium for Personal and Commercial Spaceflight in New Mexico last week.

But the final decision as to whether to let Dragon dock at the station will not come until the flight is under way.

"We'll be prepared to go all the way to the station," Block said.

SpaceX, founded, owned and operated by Internet entrepreneur Elon Musk, is one of two companies hired by NASA to deliver cargo to the station. The other is Orbital Sciences Corp which plans to debut its Taurus 2 rocket and Cygnus space station cargo capsule on a test flight next year.