Boeing Space Exploration and Space Exploration Technologies Corp. (SpaceX) said they have cleared key milestones on their funded Space Act Agreements with NASA, part of the agencyโ€™s plan to get at least one crew-carrying vehicle launching to the international space station from U.S. soil by 2017.

Boeing in May completed a series of wind tunnel tests it began in March at NASAโ€™s Ames Research Center in Moffett Field, Calif., Boeing and NASA said in May 31 press releases. Boeing tested a scale model of its CST-100 spacecraft mated to a United Launch Alliance Atlas 5 rocket.

Meanwhile, SpaceX, which like Boeing is working on a capsule-based system, finished up a review of its human certification plan with NASA.

โ€œDuring this milestone, SpaceX detailed to NASA how we are going to achieve human rating for the Dragon-Falcon 9 crew system, including how we will prove that we meet all of NASAโ€™s requirements,โ€ SpaceX spokeswoman Christina Ra wrote in a May 28 email.

Boeingโ€™s latest milestone was worth $37.8 million; SpaceXโ€™s was worth $50 million.

The current phase of NASAโ€™s Commercial Crew Program wraps up in April 2014. NASA plans to solicit proposals for a follow-on phase, intended to culminate in a crewed demonstration flight to the space station, later this year.

Dan Leone is the NASA reporter for SpaceNews, where he also covers other civilian-run U.S. government space programs and a growing number of entrepreneurial space companies. He joined SpaceNews in 2011.Dan earned a bachelor's degree in public communications...