NASA will attempt to stimulate a portfolio of private transportation providers in its commercial crew program, striking a balance between emerging and established space companies, according to new agency plans released Monday.

SpaceX's Falcon 9 rocket, a keystone of that company's plans for human spaceflight, is on the launch pad at Cape Canaveral this week for testing. Credit: SpaceX

The space agency also plans to finish a draft of human-rating standards for commercial vehicles by the end of 2010.

In a fiscal year 2011 budget estimate posted Monday, NASA unveiled several details of the commercial crew initiative, but offered no specific timetable for when the agency will begin selecting providers. NASA officials previously stated they hoped to start operational commercial flights as early as 2014, but those schedules may be optimistic.

The fastest companies say they reach initial operating capability around three years after receiving approval, and the first contracts may not be awarded until 2011.

The document suggested NASA will procure crew-carrying spacecraft in a way similar to the Commercial Orbital Transportation Services, or COTS, program that is applying government funding to SpaceX and Orbital Sciences to develop capsules to ferry cargo to the International Space Station.

Such an acquisition paradigm would provide NASA funding to commercial partners based on milestones achieved in technical development and financing. The partners would also be required to add significant private funding to the program.

The NASA budget request for 2011 includes $6 billion over the next five years for commercial crew development.

"These funds will be competed through COTS-like, fixed-price, milestone-based Space Act Agreements that support the development, testing, and demonstration of multiple commercial crew systems," the budget estimate said.

NASA awarded $50 million in seed money to five companies in early February, part of the Commercial Crew Development program that seeks to aid companies in early design and development work for key space technologies. The CCDev funding was appropriated by Congress in the 2009 stimulus package.

The CCDev work will be completed by the end of 2010, and NASA says there will be a "full and open competition for commercial development activities at the conclusion of the CCDev activities." That schedule means the outcome of any competition would likely not occur until 2011.

A key difference from the COTS program will be the inclusion of experienced companies and existing rockets in the commercial crew competition. The COTS program focused on smaller companies and new entrants in the market.

"This program will also be open to a broad range of commercial proposals including, but not limited to: human-rating existing launch vehicles, developing spacecraft for delivering crew to the ISS that can be launched on multiple launch vehicles, or developing new high-reliability rocket systems," NASA said.

That news is good for companies like United Launch Alliance, which has agreements with several spacecraft developers to use the Atlas 5 rocket. A partnership between Boeing and Bigelow Aerospace working on a space capsule and Sierra Nevada's Dream Chaser lifting body design would both launch on the Atlas 5 booster.

Artist's concept of the Dream Chaser spacecraft approaching the International Space Station. Credit: Sierra Nevada

Both teams, plus ULA, received CCDev funding earlier this month.

"I think they want to leverage the entire space community's expertise and figure out to deliver the best value for our nation to move forward," said Michael Gass, ULA president and CEO. "You want to get an opportunity to have new entrants, but you also need to honor the experience and expertise that comes with 50 years of experience."

SpaceX, Orbital and other companies are also assembling proposals for commercial crew contracts.

NASA will also strive to help fund multiple providers, but the ultimate mix of commercial partners will depend on budget demands and the companies' technical competency.

"The competition will result in a targeted portfolio of up to four companies with a mixed risk balance consisting of launch vehicles, crew capsules, and supporting technologies," NASA wrote in the budget estimate.

After the selected companies achieve development milestones and demonstrate technical and financial stability, NASA would issue contract awards for operational missions. The agency followed a similar plan with the Commercial Resupply Services contract for logistics resupply missions to the International Space Station.

In the documents released Monday, NASA also addressed concerns by the Aerospace Safety Advisory Panel in a January report slamming the safety standards of firms vying for the crew transportation job.

The ASAP report urged NASA to "promptly" establish definitive human-rating certification and safety requirements for commercial operators carrying NASA astronauts. The panel also recommended that NASA conduct extensive oversight during operations.

Although the ASAP report cautioned against canceling the Ares 1 rocket, which was scrapped in the White House budget request Feb. 1, NASA says it agrees with the panel's recommendations on developing detailed human-rating standards.

"NASA will work to complete an agency and industry-coordinated human rating draft by the end of 2010," the agency said.