Two of the companies competing in NASA's Commercial Crew Development (CCDev) program have been busy in the wind tunnel. The overly secretive Blue Origin broke its silence this week with pictures of its unique capsule design and Sierra Nevada Corporation also released news of its Dream Chaser, completing scale model wind tunnel testing in Texas.

Blue Origin, the space company started by Amazon.com founder Jeff Bezos, is easily the quietest of the CCDev participants to provide astronaut transportation to the International Space Station and other low-earth-orbit missions. Little is known about what is going on at the Seattle-area company, with news only leaking out a few times a year. This week's update provided a few more details about the innovative design the company is developing for its creatively named Space Vehicle.

Instead of using a more traditional symmetrical capsule design, the Blue Origin Space Vehicle uses a biconic shape with one side of the capsule flattened and a split flap (most likely two) that can be used for directional control. The flap can be seen in the multicolored image above from the computational fluid design program used to develop the spacecraft. Similar designs have been developed in the past, most notably McDonnell-Douglas' legendary Advanced Maneuvering Reentry Vehicle (AMaRV) developed in the 1970s. This vehicle also used split flaps for directional control, though it was designed to deliver weapons launched from a Minuteman missile.

Blue Origin's president Rob Meyerson says the Space Vehicle's design is just one of the features he hopes will enhance the safety and affordability of spaceflight. “Our Space Vehicle’s innovative biconic shape provides greater cross-range and interior volume than traditional capsules," he said in the press release, "without the weight penalty of winged spacecraft.”

Scale model of Blue Origin's Space Vehicle in the wind tunnel. Photo: Blue Origin

The Blue Origin design increases the lift-over-drag ratio of the spacecraft compared to a traditional capsule like those used during NASA's Mercury, Gemini and Apollo programs that essentially free-fall during re-entry, only allowing small amounts of steering via small rocket thrusters. The design gives it the ability to better control the descent as well as making relatively large course corrections if needed, though not to the same extent as a winged vehicle like the space shuttle. The company conducted more than 180 tests at Lockheed Martin's high-speed wind tunnel facility in Dallas. The Space Vehicle is a separate program from Blue Origin's New Shepard suborbital vehicle, which underwent test flights late last year.

Texas was also the location for Sierra Nevada's recent wind tunnel testing of its CCDev vehicle, the Dream Chaser. Originally developed by SpaceDev, the Dream Chaser is a lifting body design based largely on NASA's HL-20, which began testing in the 1980s.

Sierra Nevada Corporation's Dream Chaser spacecraft during wind tunnel testing. Photo: SNC

Several lifting body vehicles were tested by NASA in the '60s, including the Northrop M2-F2, which was made famous as part of the intro for the television show The Six Million Dollar Man. The body design develops lift from the fuselage rather than using traditional wings. Like the Blue Origin Space Vehicle, the goal is to add more control and range, filling in the gap between a free-falling capsule and a true winged vehicle.

Sierra Nevada's Dream Chaser is designed to be launched at the top of a rocket – initially an Atlas V – like a capsule but would glide back to a runway similar to the Space Shuttle. The company said the successful low-speed wind tunnel testing at Texas A&M University provided data that will be used to define the flight characteristics of the lifting body design. Sierra Nevada is planning for the first test flight of the Dream Chaser this fall.

To help keep all of the acronyms related to the new commercial space push straight, NASA's CCDev program is part of the agency's drive to fund the development of commercial replacements for the space shuttle to deliver people and payloads into low earth orbit. The program is run by NASA's Commercial Crew and Cargo Program Office, which appears to be named so NASA could use the clever C3PO acronym when talking about the program.

In addition to Blue Origin and Sierra Nevada Corporation, CCDev is also providing funding support for Boeing's CST-100 and SpaceX's Dragon spacecraft. SpaceX is scheduled to launch the Dragon on May 7 for a mission to the International Space Station as part of NASA's Commercial Orbital Transportation Services (COTS) contract to deliver cargo to the ISS. SpaceX is the only company developing a vehicle for launching both astronauts with the CCDev program and cargo with the COTS program.