Crew Return Vehicle

The Crew Return Vehicle, sometimes called the Assured Crew Return Vehicle, was a proposed dedicated lifeboat or escape module for the International Space Station. A number of different designs were studied over roughly two decades, and several flew as developmental test prototypes, but none of them became an operational part of the station. Since the station's first permanent crew arrived in 2000, the emergency return role the Crew Return Vehicle would have filled has instead been covered by Soyuz spacecraft and, more recently, by SpaceX's Crew Dragon, each rotated out roughly every six months. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/