NASA will use Space Act agreements - instead of a formal Request for Proposals leading to a contract - to continue to push its commercial crew program forward.
The change in procedure is the result of uncertain funding, said NASA's Associate Administrator William Gerstenmaier.
NASA had been expected to issue an RFP on Monday, which would have culminated in the space agency signing a contract around June with at least two private companies to design a system to carry U.S. astronauts to the International Space Station.
Due to funding uncertainties, "it is really tough to lock into a a firm fixed price contract with the number of providers that can keep us moving forward," Gerstenmaier said,
NASA received $406 million for its commercial crew program in 2012, significantly less than the amount President Barack Obama had asked for.
If the agency had continued with its original plan for a formal contract, the uncertainty over funding - particularly in future years - could have: limited the number of companies selected or forced the contract to be repeatedly renegotiated based on funding changes.
The Space Act allows NASA "to carry more providers through this period," Gerstenmaier said. "We would like to carry two providers as a minimum or actually more. ... We think competition is a key piece."
NASA used a Space Act agreement for its commercial cargo program, and originally the private companies vying to win the commercial crew contract urged NASA to continue this. However, NASA argued that contracts allow the agency greater control and greater involvement in dictating what kind of system it needs.
Gerstenmaier said the agency still believed that was the case. Under a Space Act, "there is some potential risk at the end of this phase...it doesn't ensure we get exactly what we need coming out the other side."
But he said it was the best case scenario due to the funding uncertainty, and noted the companies have seen NASA's requirements so they know what the agency is looking for. These next competitively bid Space Act agreements, expected to be signed around June, would then lead to a design review and a contract for services.
Gerstenmaier also confirmed that they were now looking at a launch in 2017 - a year later than initially planned.