Faced with a deep cut in its budget request for commercial crew development in fiscal 2012, NASA will continue to use Space Act Agreements (SAAs) to seed work on the private spacecraft it needs to carry U.S., European, Japanese and Canadian astronauts to the International Space Station (ISS).

NASA had planned to issue a request for proposals Monday under the standard Federal Acquisition Regulations (FAR) for the third round of its Commercial Crew Development (CCDev) program. But with only $406 million of the $805 million requested for the current fiscal year, the agency has decided to opt for the “flexibility” it gains from the SAA approach over a fixed-price FAR contract.

“With a firm fixed-price contract, if we don’t get the funds that we anticipated it makes it tough to renegotiate the contracts,” says William Gerstenmaier, associate administrator for human exploration and operations. “There’s an inefficiency with renegotiating that contract. We don’t actually get the product we want out of this activity. We actually get a bunch of contract change paper back and forth, which isn’t a very good way of doing business.”

Under SAAs, which were used in the first two phases of CCDev, NASA in general has less say over the work a spacecraft developer does, and has less insight into it. Some of the agency’s CCDev partners in the second phase of the work resisted the announced shift to FAR procurement.

“We applaud NASA’s decision to use Space Act Agreements for the next round of commercial crew and look forward to the competition,” says Space Exploration Technologies (SpaceX) President Gwynne Shotwell.

Gerstenmaier says the public interest should be protected by the competitive nature of the procurement, which so far is funding spacecraft work by Blue Origin, Boeing, Sierra Nevada and SpaceX, and by clear public specifications of NASA’s requirements for a human-rated spacecraft that can dock with the ISS.

“The competition between the providers is going to make them want to adhere as much as they can to the requirements that we’ve defined, so I think we’ve mitigated that risk,” Gerstenmaier says. “But there is a risk there that we won’t get exactly what we had anticipated.”

To ensure that any vehicles resulting from the competition meet NASA’s requirements, there will be a certification period after the expected 21-month period of the CCDev-3 SAAs. Gerstenmaier conceded that may take longer than would be the case under a contract approach, which was already anticipated to push beyond the end of NASA’s current contract to buy seats on Russian Soyuz vehicles for the astronauts it flies to the ISS.

That contract will end in the spring of 2016, he says, so the agency will negotiate for seats on two more Soyuz flights a year after that. The change will also require an extension to NASA’s exemption in non-proliferation law that allows procurement of the Russian services. Gerstenmaier says NASA has briefed its congressional oversight committees on the change in procurement strategy, and is working within the executive branch on asking Congress for a continuation of its exemption on doing business with Russia.

The agency is still working out the details of its new CCDev procurement strategy, which will delay release of an announcement for proposals until the first quarter of 2012. Gerstenmaier says the agency hopes to award “multiple” contracts next summer.