Up to seven passengers can ride Dream Chaser into space. The spacecraft hitches into orbit on the tip of a rocket, detaches, and is designed to back in to the docking station of the space station. Dream Chaser has not yet flown, but engineers towed the craft for runway evaluations and dropped it from helicopters for glide tests.
Space planes have advantages. Instead of passively plummeting through the atmosphere like a capsule, they can maneuver, change their landing destination midflight, and be reused after a short turnaround. But two U.S. space shuttle disasters suggest that space planes are not ideal for orbital missions. By carrying cargo and crew in the same vehicle, the shuttle required that everything be carried aloft on expensive, human-rated equipment. Also, tacking the shuttle alongside its boosters and fuel tank allowed for the kind of debris strike that doomed Columbia. But Sierra Nevada Space Systems is betting it can redeem the reputation of the orbital space plane with the Dream Chaser, a winged crew-delivery vehicle that’s competing for NASA contracts to deliver people to the ISS.
Dream Chaser will avoid the shuttle’s main flaws by carrying crew separately from cargo and by launching atop an Atlas V rocket. But it will retain its advantages, including a maximum deceleration on reentry of only 2 g’s—1 g less than what a capsule experiences. The spacecraft also has flexibility as to where it can land. “Anywhere a 737 can land, Dream Chaser can too,” says Mark Sirangelo, vice president of Sierra Nevada.
The Dream Chaser spacecraft, originally envisioned to fly with astronaut crews, will now fly on space missions with cargo deliveries heading for the International Space Station. That change means the spaceship will return to Earth on autopilot, using navigation aids to descend to a runway, deploy its landing gear and touch down like NASA’s space shuttles.
More Information can be found at http://spacenews.com/sierra-nevada-corp-prepares-for-next-round-of-dream-chaser-tests/