DECADAL SCIENCE STRATEGY SURVEYS: REPORT OF A WORKSHOP by National Research Council of the National Academies

Author:National Research Council of the National Academies
Language: eng
Format: epub
Tags: Policy for Science and Technology
Publisher: NATIONAL ACADEMY PRESS
Published: 2007-07-03T00:00:00+00:00

There was much discussion about how cost models could be used in surveys. Most participants believe they might have limited utility or accuracy since most missions are far short of being ready for PDR at the time of a survey. That said, survey committees need to be educated consumers of cost models and need to have members who have cost modeling expertise. It was also suggested that survey committees should contract out at least two independent cost estimates. It was clear from the discussion that missions (particularly large ones) need to have the technology development well understood or characterized before a cost estimate can be reasonable. It was suggested that a flagship mission should not go forward if its technology is not fully understood and should be recommended only as a candidate for technology development until it is better understood. Participants also noted that cost estimates usually do not take into account other key factors (such as the cost of the “marching army”) if a problem introduces a significant delay in the development schedule. That situation demands that a large reserve be maintained for such problems, and that reserve should be off-limits to other program needs (e.g., technology development). True reserves should be a critical component of any mission budget and should probably be ~20 percent of the total mission cost estimate.

The discussion turned to whether there were also lessons to be learned with respect to how NSF plans and manages large, ground-based projects. Some participants thought that there was some commonality with space missions, but others saw the terrestrial construction industry as quite different from the aerospace industry. Furthermore, the NSF major research equipment and facility construction budget represents only about 5 percent of the total NSF portfolio, and final cost estimates for projects take a long time. The National Science Board signs off on these large projects after an extended definition phase, and the board approves projects with fixed budgets. NSF facility construction projects are also separate from NSF division research budgets. Therefore, while development costs do not affect the research division, the long-term operational costs must be accounted for within the research budget.

There was considerable discussion of the cost risks associated with international collaboration. NASA representatives pointed out that NASA has explored these risks recently and is moving toward not getting too dependent on international contributions. Participants cited the contrasting examples of the European Space Agency’s Huygens Probe and the German propulsion system on the Galileo mission. The Huygens atmospheric entry probe would not have happened without international cooperation, but the probe was separate from the rest of the Galileo mission and the core mission was not dependent on it. On the other hand, because the German propulsion system was highly integrated into the Galileo spacecraft, it had an impact on the overall mission cost. Others mentioned that when technology development is outsourced to other countries it diminishes the robustness of the technology coming from our nation’s aerospace community. Some participants, however, reminded their colleagues that one

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