The Orbital Space Plane (OSP) program was a NASA spaceplane concept in the early 2000s designed to support the International Space Station requirements for crew rescue, crew transport and contingency cargo such as supplies, food and other needed equipment.
With the initiation of the Constellation program in 2004, NASA transferred the knowledge gained on the OSP to the development of Crew Exploration Vehicle, an Apollo-style capsule with separate crew and service modules.
