NASA has nearly finished a study on the feasibility of accelerating the crew transport portion of its Commercial Orbital Transportation Services (COTS) program, which for now remains focused exclusively on cargo.

During testimony April 3 to the House Science subcommittee on space and aeronautics, Richard Gilbrech, NASA's associate administrator for exploration, said the agency would be happy to share the results of the study with lawmakers as soon as it is completed. "We're in the final stages of vetting that," he said.

SpaceX and Orbital Sciences have been funded under the $500 million COTS program, which was begun to nurture commercial options for transporting cargo - and eventually crew - to the International Space Station (ISS).

So far only SpaceX has said it also plans to develop crew transport capability for COTS. Some lawmakers have expressed the desire for NASA to speed that part of the effort to help narrow the expected gap in U.S. human spaceflight capability between the 2010 retirement of the space shuttle and the introduction of NASA's Orion vehicle, which is not slated until early 2015.

SpaceX plans its first demonstration of cargo transport to the ISS in March 2010. An earlier target of September 2009 had to be abandoned because of welding issues with the Merlin 1C engine on SpaceX's Falcon 9 rocket. (DAILY, Feb. 28).

A crucial milestone for SpaceX will be the next launch attempt for its smaller Falcon 1, which is set for June from Kwajalein Atoll in the Marshall Islands. It will be the third Falcon 1 launch attempt, after two launch failures.