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December 29, 2010 Vol. 3, Issue 12


NASA faces a potential gap in medium class launch vehicles for science missions due to the discontinuation of the Delta II.

The Delta II launch vehicle has been a workhorse for NASA science missions for decades. After its last launch in 2011, NASA will not have another certified vehicle in its cost and performance range to take its place. The Government Accountability Office (GAO) assessed NASA’s transition and risk mitigation plans to determine the agency’s level of preparedness for this eventuality.

GAO found that the Launch Services Program is taking steps to address the risk associated with safely flying the last Delta II flights. Regarding the gap that will be left by the retirement of the Delta II, it noted that NASA expects to certify the Space X Falcon 9 and the Orbital Taurus II, medium class vehicles designed to resupply the International Space Station, for use on science missions. GAO reported that NASA has not developed detailed estimates of the time and money required to resolve technical issues likely to arise during the launch vehicle certification process, and it recommended that the NASA Administrator should require:

  • NASA’s Science Mission Directorate—in conjunction with NASA’s Space Operations Mission Directorate—to perform a detailed cost estimate to determine the likely costs of certification and the trade-offs required to fund these costs.
  • That the costs identified through developing the detail cost estimate are adequately budgeted for and identified by the Science Mission Directorate.
  • The Science Mission Directorate to identify and budget for additional contingency funding for the projects requiring a medium launch capability vehicle and approaching their preliminary design review prior to certification of Falcon 9 and Taurus II that could be impacted by additional costs associated with certification of these vehicles, including the need to address technical issues and shoulder delays in the certification process.

Read the GAO report.

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