NASA X-38

The X-38 Crew Return Vehicle (CRV) was a prototype for a wingless lifting body reentry vehicle that was to be used as a Crew Return Vehicle for the International Space Station (ISS). The X-38 was developed to the point of a drop test vehicle before its development was cancelled in 2002 due to budget cuts

The crew size for the ISS depends upon the crew return capability: the crew is limited to three because the Russian Soyuz TMA vehicle that will remain docked to the ISS can only hold three people. Since it is imperative that the crew members be able to return to Earth if there is a medical emergency or if other complications arise, a Crew Return Vehicle able to hold up to seven crew members was planned from the outset: this would have allowed the full complement of seven astronauts to live and work onboard the ISS. NASA has designed several crew return vehicles over the years with varying levels of detail.