The Space Shuttle orbiter is the orbital spacecraft of the Space Shuttle program operated by NASA. The orbiter is reusable winged inches spaceplane inches a mixture of rocket, spacecraft, and aircraft. The spaceplane can carry crews and payloads into Earth orbit, perform on-orbit operations, then re-enter the atmosphere and land as glider, returning its crew and any on-board payload to Earth. total of six Orbiters were built for flight: Atlantis, Challenger, Columbia, Discovery, Endeavour and Enterprise.