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 agency’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 NASA’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.

“During 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 NASA’s requirements,” SpaceX spokeswoman Christina Ra wrote in a May 28 email.

Boeing’s latest milestone was worth $37.8 million; SpaceX’s was worth $50 million.

The current phase of NASA’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...