Space suit.

Louisville-based Space Systems challenges the rejection of its Dream Chaser with the GAO.

Louisville-based Sierra Nevada files formal protest over rejection of its bid for NASA’s commercial crew contract. »

Sierra Nevada Corp.’s Louisville-based Space Systems on Friday filed a formal protest with the U.S. Government Accountability Office over rejection of its bid for NASA’s commercial crew contract.

Space Systems lastweek lost out on the NASA contract for its Dream Chaser spacecraft, which would have shuttled astronauts to the International Space Station. NASA on Sept. 16 announced the $6.8 billion total contract would be split between Chicago-based Boeing Co., which received $4.2 billion, and Elon Musk’s SpaceX, which received $2.6 billion.

Sierra Nevada, in a news release, said the awards to SpaceX and Boeing will cost the U.S. government up to $900 million more on the contract than the system Sierra Nevada proposed. In its bid solicitation, NASA weighted price equally with the combined value of the two other mission criteria: mission suitability and past performance, the company said.

“SNC’s Dream Chaser proposal was the second lowest priced proposal in the competition,” the company wrote.

The company also said the winged Dream Chaser is amore flexible craft than the capsule styles proposed by SpaceX and Boeing. Its design, the company wrote, “provides awider range of capabilities and value, including preserving the heritage of the space shuttle program through its design as a piloted, reusable, lifting-body spacecraft.”

Sierra Nevada, a 51-year-old company based in Sparks, Nev., said it has never before filed a legal challenge to a government contract award but felt it had no alternative.

“However, in the case of the (Commercial Crew Transportation Capability) award, NASA’s ownsource-selection statement and debrief indicate that there are serious questions and inconsistencies in the selection process,” the company wrote.

Space Systems this week let go about 90 people in the wake of the contract loss.

Space Systems announced in January a November 2016 launch date for its first Dream Chaser orbital mission, aswell as an expansion along Florida’s space coast, sharing NASA facilities at Kennedy Space Center with Jefferson Countybased Lockheed Martin Space Systems.

Space Systems chief Mark Sirangelo said Wednesday he could not comment on how the layoffs would affect Space System’s 2016 launch plans.

Space Systems plans to continue developing the Dream Chaser, including a near-term bid on NASA’s second Commercial Resupply Services effort, according to a company spokeswoman. That contract is expected to be awarded in early 2015, according to NASA’s website.