One of the commercial vehicles vying to fill the void left by the retired space shuttles for carrying Americans into orbit from U.S. launch pads took to the skies over California's Edwards Air Force Base on Thursday for captive-carry testing.

Credit: NASA / Ken Ulbrich

Slung beneath a Sikorsky S-64 helicopter operated by Erickson Air Crane, the engineering test article of Sierra Nevada's Dream Chaser spacecraft spent two hours over the military base in the high desert to check systems before upcoming landings.

The vehicle's flight computer, guidance, navigation and control systems, aerosurfaces were tested during the captive-carry. The landing gear and nose skid also were deployed during flight, officials said.

"Today is the first time we have flown a fully functional Dream Chaser flight vehicle, and we are very pleased with the results," said Mark Sirangelo, corporate vice president and head of SNC's Space Systems.

The event flew a distance of three miles over the dry lake bed at a maximum altitude of approximately 12,400 feet. Officials said spacecraft followed the projected path it will fly during future approach-and-landing tests.

"Our team represents the very best in collaboration between industry and government. We have worked closely with NASA, Dryden and the Air Force to reach this important milestone in our flight test program. We will continue to work together to prepare for the approach-and-landing free-flight test," said Sirangelo.

Analogous to development of the space shuttle orbiters, the prototype Enterprise conducted a series of captive-carry flights atop the 747 carrier aircraft in 1977 at Edwards, paving that way to five piloted free-flights to test the approach-and-landing aspects of the vehicle that year.

An artist's concept of Dream Chaser atop an Atlas 5 for launch. Credit: Sierra Nevada

Dream Chaser, a reusable lifting body vehicle with wings, will be launched atop a United Launch Alliance Atlas 5 rocket carrying a crew of seven astronauts for docking to the International Space Station.

The vehicle then returns to Earth for landing on a conventional runway.

"We look forward to seeing Dream Chaser land on the same runway as the space shuttle orbiters once did as we move forward in the development of the next-generation crew transportation vehicle," said Sirangelo.

Dream Chaser is competing against capsules -- Boeing's CST-100 and the SpaceX Dragon -- in NASA's Commercial Crew program to resume U.S. human spaceflight launches in 2017, if the funding is provided by Congress.

Crews living aboard the space station have been launching on Russian Soyuz vehicles since the Columbia accident in 2003, with some limited single-crewmember rotations performed by the shuttles before their retirement in 2011.

Credit: NASA / Ken Ulbrich

Sierra Nevada plans to begin a series of free-flight tests at Edwards this fall. The initial landings will be automated, then progress into piloted ones.

"It's great to see real American-made hardware taking flight right here in the U.S.," said Ed Mango, NASA's Commercial Crew Program manager. "This is just the start of an exciting flight test campaign for SNC's Dream Chaser."

Recent work verified the spacecraft's computer and software systems, instrumentation and steering performance, and Dream Chaser's braking and landing systems through a series of ground tow tests.

"Watching Dream Chaser undergo tow testing on the same runway where we landed several space shuttle orbiters brings a great amount of pride to our Dream Chaser team. We are another step closer to restoring America's capability to return U.S. astronauts to the International Space Station," said Steve Lindsey, SNC's Space Systems senior director of programs and former NASA astronaut.

Sierra Nevada is eligible for $227.5 million in funding from NASA by completing 12 milestones through August 2014.