Space Exploration Technologies’ (SpaceX) Falcon 9 rocket was hoisted into vertical launch position Feb. 20 at the Cape Canaveral Air Force Station in Florida Feb. 19 in preparation for its maiden test flight later this year. The company is one of two firms contracted by NASA to provide unmanned cargo shipments to the international space station on commercially built spaceships.

The Hawthorne, Calif.-based company’s smaller Falcon 1 rocket completed its second successful launch into orbit last year. It was the fifth launch of a Falcon 1, which suffered three failures before hitting success on try No.4. A Malaysian satellite rode the fifth Falcon 1 rocket to orbit in last summer’s flawless launch.

Liftoff of the first Falcon 9 rocket is expected to come sometime in the next few months, possibly by May, SpaceX officials have said. But the final launch date hinges on successful systems and engine checks and range safety approval.

Fueling rehearsals, called a wet dress, and a short, 3.5-second static test firing of the Falcon 9’s first-stage engines are the next major milestones.

SpaceX has not set specific dates for wet dress or static fire as [the] schedule will be driven by the satisfactory completion of all test objectives and a thorough review of the data,” SpaceX officials said in a Feb. 21update.

This is not the first time SpaceX has hauled its 55-meter Falcon 9 rocket vertical atop its launch pad. The company assembled and moved its first Falcon 9 to pad in January 2009 as part of integration tests.

But this year, SpaceX aims to launch its first Falcon 9 missions. The rocket is designed to haul SpaceX’s unmanned Dragon spacecraft, which the company plans to use to fly 12 cargo missions to the space station under a $1.6 billion contract with NASA.

Another company, Virginia-based Orbital Sciences, is building its Cygnus spacecraft and Taurus 2 rocket to launch eight unmanned cargo flights to the space station under a separate $1.9 billion contract.

Both companies have expressed an interest in modifying their vehicles to carry astronauts. NASA is banking on commercial spacecraft arising to ferry astronauts to orbit since its Constellation program in charge of replacing the shuttle fleet with new rockets and vehicles was slated for cancellation in the agency’s 2011 budget request.