The space shuttle is the primary vehicle supporting the assembly  and resupply of the station. NASA plans to return the shuttle to flight in July 2005. Figure 2 shows NASA’s proposed plan for operational support of the space  station until 2016. NASA’s 2004 Assessment Was Based on Insufficient Knowledge for Concluding Space Shuttle Was Best Launch Option, but Opportunities Now Exist for More Detailed Study

According to program officials, NASA’s 2004 informal assessment  concluded that alternative launch vehicles would present operational  risks, technical challenges, and long program delays and would cost more  than returning the space shuttle to flight, making the space shuttle the best  option for both assembly and logistics missions through the end of the  decade. According to previous studies and our discussions with  commercial industry representatives, the time involved for developing an  alternate capability would probably preclude assembly missions from  consideration. Furthermore, NASA officials did not document these informal proceedings  and decisions reached; therefore, the thoroughness of any assessment of  alternatives cannot be verified, nor can their conclusions be validated. NASA is currently evaluating responses from commercial industry on  different ways to provide logistics services to and from the space station. However, NASA did not have sufficient knowledge to conclude that the  shuttle was the best option for logistics missions prior to its retirement of  the shuttle in 2010. When asked about the details  of the assessment, NASA officials indicated that the informal assessment  was based primarily on the expertise within the headquarters and they did  not formally document the decision paths. Combining the information gathered from commercial industry and a  better definition of space station requirements, NASA officials agreed  there is an opportunity to perform a more comprehensive assessment of  alternatives, especially for the logistics missions late this decade. While we recognize that  the extensive experience of its senior managers is an important element in  evaluating alternatives, NASA did not have the full breadth of knowledge  necessary to perform a comprehensive assessment of alternative launch  vehicles to enable it to conclude the space shuttle was the best option to  support space station operations. However, NASA’s recent request for  information from industry offers the agency an opportunity to enhance its  knowledge of alternatives to the space shuttle for providing logistics  support for the space station and to explore the use of alternatives to the  existing space shuttle manifest currently under review. Although alternate  vehicles would not be available for missions to the space station until later  this decade and difficult to use for assembly missions, several of the space  shuttle’s final flights are planned logistics support missions that might be  conducted using alternative launch vehicles. Recommendation for Executive Action

To better position the agency to determine the best available option for  providing logistics support to the space station, we recommend the NASA  Administrator take the following three steps:    Direct current efforts to explore other space launch options to utilize a  comprehensive and fully documented assessment of alternatives that  matches mission requirements, and associated manifest, with the  launch vehicles expected to be available;    As part of this assessment, (a) determine the development and  operation costs associated with these potential alternatives and (b)  perform a detailed analysis of these alternatives to determine the best  option for delivering the logistics cargo required for space station  operations prior to and after space shuttle retirement; and    Ensure this assessment is completed before any NASA investments are  made for commercial space transportation services to the space  station.
Why GAO Did This Study

The National Aeronautics and Space Administration's (NASA) space shuttle fleet has been key to International Space Station operations. Since the grounding of the fleet in February 2003, Russia has provided logistics support. However, due to the limited payload capacity of the Russian space vehicles, on-orbit assembly of the space station stopped. In May 2004 and in February 2005, NASA testified before the Congress that it had assessed using alternative launch vehicles to the space shuttle for space station operations. NASA concluded that using alternatives would be challenging and result in long program delays and would ultimately cost more than returning the space shuttle safely to flight. Yet uncertainties remain about when the space shuttle will return to flight, and questions have been raised about NASA's assessment of alternatives. GAO was asked to determine whether NASA's assessment was sufficient to conclude that the space shuttle is the best option for assembling and providing logistics support to the space station.

What GAO Found

NASA's 2004 assessment identified significant challenges associated with using alternative launch vehicles for space station assembly and operation. According to previous studies and our discussions with industry representatives, these challenges would likely preclude using alternative vehicles for assembly missions. However, NASA's assessment was insufficient to conclude that the shuttle was the best option for logistics support missions prior to the proposed retirement of the space shuttle in 2010. NASA relied primarily on headquarters expertise to conduct the informal assessment, and while we recognize that the extensive experience of its senior managers is an important element in evaluating alternatives, NASA officials did not document the proceedings and decisions reached in its assessment. As a result, the existence of this assessment of alternatives cannot be verified, nor can the conclusions be validated. NASA is currently evaluating responses from a September 2004 request for information from various commercial space transportation industries that could provide launch services to support space station operations, following retirement of the shuttle in 2010, until the station's planned retirement in 2016. NASA officials indicated that a commercial launch capability to support space station operations is possible prior to the proposed shuttle retirement in 2010, but stated that this capability would not eliminate any of the scheduled space shuttle flights. NASA is also re-examining its requirements for the type of scientific research to be conducted on the space station as well as the manifest requirements of the space shuttle. Combining the information gathered from commercial industry and a better definition of space station and shuttle requirements, NASA officials agree there is an opportunity to perform a more comprehensive assessment of alternatives, especially for logistics missions late this decade.