NASA: Challenges in Completing and Sustaining the International Space Station

The International Space Station (ISS), the most complex scientific space project ever attempted, remains incomplete. NASA expects the station's final construction cost will be $31 billion and expects sustainment costs through the station's planned retirement in fiscal year 2016 to total $11 billion. The space shuttle, the only vehicle capable of transporting large segments of the station into orbit, is critical to its completion. NASA plans to complete ISS assembly and retire the shuttle in 2010 in order to pursue a new generation of space flight vehicles, which will not begin to be available until 2015. To provide crew rotation and logistical support during this 5-year gap, NASA plans to rely on spacecraft developed by the commercial sector and other countries. In light of these circumstances, GAO examined the risks and challenges NASA faces in (1) completing assembly of the ISS by 2010 and (2) providing logistics and maintenance to the ISS after 2010. GAO's work to accomplish this included reviewing budget, planning, and other documents from NASA; reviewing NASA officials' testimonies; and interviewing NASA and foreign space program officials.