WASHINGTON — Dulles, Va.-based Orbital Sciences Corp. is throwing its hat into NASA’s commercial-crew transport ring with plans to develop a crew capsule based on the company’s Cygnus cargo module, according to industry sources.

Cygnus and its Taurus 2 medium-class launcher are currently in development with help from $171 million in NASA funding won in February 2008 under the agency’s Commercial Orbital Transportation Services (COTS) demonstration program. NASA in December awarded Orbital a $1.9 billion contract for resupply missions to the international space station.

“We’re definitely supportive of the idea of commercial crew,” Orbital spokesman Barry Beneski said Sept. 11. “We were initially focused on cargo, but now that the Augustine recommendations are out, there seems to be a more serious look at how the private sector can contribute, and that’s what Orbital has done for basically our whole history.”

An independent panel chartered by the White House in May to review NASA’s human spaceflight program released a summary report Sept. 8 endorsing commercial services to transport crews to and from low Earth orbit.

The panel, led by former Lockheed Martin chief Norm Augustine, found that while a space architecture crafted to provide opportunities to the private sector would not come without risks, it could save NASA money.

“As we move from the complex, reusable shuttle back to a simpler, smaller capsule, it is an appropriate time to consider turning this transport service over to the commercial sector,” the summary report states. “This approach is not without technical and programmatic risks, but it creates the possibility of lower operating costs for the system and potentially accelerates the availability of U.S. access to low-Earth orbit by about a year, to 2016.”

NASA’s space shuttle is slated to retire in 2010, and the agency’s planned replacement is scheduled to debut in 2015. However, the Augustine panel believes that system will not be ready before 2017.

In public meetings held this summer, the Augustine panel indicated it would urge the White House to set aside at least $2.5 billion to stimulate private-sector competition to develop a commercial crew capability.

Beneski said a crew variant of Orbital’s Cygnus pressurized cargo module capable of carrying three or four astronauts, along with a human-rated version of Taurus 2, could be developed at a cost of  $2 billion to $3 billion.

One industry source identified Boeing as a potential partner in the effort, which would involve adding a new liquid-hydrogen second stage to the Taurus 2, giving it the thrust needed to carry around 8 metric tons to the space station. This would accommodate an Apollo-sized capsule based on the Cygnus cargo vehicle design along with a service module.

Although Beneski declined to comment on the time that will be necessary to develop a crew transport capability, one industry source estimated four years from contract award.

“There are those companies who think it can be done more quickly and more cheaply than we do,” Beneski said. “On the other hand, there are participants in the industry that are a little more wedded to the current way of doing things. We’re somewhere in the middle.”

Hawthorne, Calif.-based Space Exploration Technologies (SpaceX) is developing the Falcon 9 rocket and Dragon cargo capsule with COTS funding help and has a $1.6 billion contract to deliver supplies to the international space station. SpaceX Chief Executive Elon Musk said Sept. 9 a man-rated version of Dragon could be fielded within three years and carry seven astronauts to low Earth orbit at a cost of about $20 million per seat.

Beneski said a COTS-like development program that minimizes costly NASA oversight would keep costs low while speeding development.

“Under the right conditions, the commercial sector can contribute and be successful, but we don’t underestimate the complexity, and the challenges, and the cost,” he said.