 The reentry motor was a solid propellant, and maneuvering thrusters utilized cold gas, so that it would have had a five-year on-station life cycle.The design was rejected, though, in June 1996 in favor of the NASA CRV/X-38 program.Besides referring to a generalized role within the ISS program, the name Crew Return Vehicle also refers to a specific design program initiated by NASA and joined by the ESA.