United Launch Alliance (ULA) and NASA have announced the signing of an unfunded space act agreement (SAA) to develop human-rating the Atlas V rocket.

The agreement, though unfunded, will allow NASA and ULA to exchange information on human ratings standards, a job expected to take six to nine months. Specifically, the contract will center around the emergency detection system, as did a funded 2010 award under Commercial Crew Development (CCDev) round one. ULA failed to win a grant under 2011's CCDev 2. Both parties maintain that few changes will be required to modify the rocket to NASA's stringent human spaceflight requirements. The system will only be certified to carry people after integrating the rocket and as-yet-undecided spacecraft, which is not included in the SAA.

"We've maintained for quite a while that the Atlas can be ready by the time any spacecraft is ready. Best case, and this depends on funding of the program, is three to four years" said ULA business development manager Dr. George Sowers. "Since the Atlas V vehicle is flying, and has flown 26 times, we don't expect to do more testing on the vehicle itself," he added.

Atlas V, developed under contract to the US Air Force, has launched 26 times to date, with a single partial failure recorded when the Centaur upper stage ceased firing slightly early. ULA has launched several NASA payloads on the Atlas V, including the Mars Reconnaissance Orbiter and New Horizons probe.

"This vehicle has flown some of the highest-value payloads from the DOD side as well as the NASA side," said Ed Mango, NASA commercial crew development program manager. "It has the pedigree that we think we can get through the risk assessment pretty quick."

Several companies developing commercial crew vehicles have approached ULA to use the rocket. "The Atlas V appears to be the vehicle of choice," said Sowers, though he declined to specify further. Sierra Nevada and Boeing are both examining the Atlas 5 as a vehicle for their commercial crew spacecraft. "We anticipate using the lower end of the Atlas performance range for the commercial crew," added Sowers.

Source: Flight International