This paper updates a previous effort investigating how the evolution of initial concept designs are related to the cost and schedule growth of missions. 12 The paper shows examples of the design evolution, and associated cost and schedule growth, for twenty historical NASA missions. Issues behind the cost and schedule growth of missions are varied, but in part may be attributed to systems that have changed substantially from those examined at initial concept through to launch. Historical resource growth is investigated for a variety of missions and mission types to provide guidelines and lessons learned to be used during the initial conceptual design stage for future missions. The data developed for the paper should help both project managers and cost and schedule estimators to develop more robust estimates earlier in the design process.
NASA science instruments have had a history of developmental delays. These development delays can lead to cost growth for the overall mission, as shown in recent studies of NASA missions and a larger historical data set. An analysis was conducted to assess if a new mission development process, labeled instrument first, spacecraft second (IFSS), could provide reduced cost and schedule growth in future missions by minimizing the impact of instrument development issues on mission development. A cost and schedule analysis was conducted for representative Tier 2 and Tier 3 Earth Science Decadal Survey missions to quantify the benefits. The results indicate that the savings resulting from such an approach is on the order of $2.5B, making more funding available for future missions, while providing a less volatile and more manageable mission portfolio. This paper reviews the results of this analysis and assesses the implications of implementing such a mission development process by showing the approach on specific mission development examples.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.