Kennedy Space Center NextGen Website
NASA Space Systems Cost Models
For time/processes - see Simulations
The term "model" is used here in the sense of an abstraction, an elaborate thought experiment, where mathematical formulas come together to create a predictive framework for the analysis and understanding of future systems. A model is different than a simulation, with models generally focusing on "what", for example a type of engine or technology, and "how" it is acquired.
Objectives in modeling space systems life cycle costs:
- Launch systems vs. in-space, spacecraft costs
- Development vs. operations costs
- Direct vs. indirect costs
- Industry (price to the government, procurement costs to the government, for contractor, partner, support contractors, etc.) vs. government costs (NASA civil servants, personnel costs, or other costs for government program / project management, acquisition management, etc.)
- Understanding Causality
- What causes a cost (not the same as what comprises a cost)
- "What" vs. "How" as cost factors - Technical (what, design, technology, characteristics) and non-technical cost contributions (how, acquisition approach, cost-plus or commercial, other transaction authority, process, practices, etc.)
- Identifying Significance
- Space systems characteristics and approaches that are drivers for significantly improving affordability and reliability
- "Why" - Benefits
The current Life Cycle Cost (LCC) model
Older (inactive/archival) cost models, including data:
- LLEGO (2006-2010): This model emphasized reusable space transportation vehicle design (what) as well as processes (how), together for the first time. With an improved understanding of direct vs. indirect costs, what comprised costs versus what caused costs, LLEGO was used in support of many NASA studies. One of these was the independent cost analysis of parts of the NASA Constellation program.
- SFAC (2005): This model, unlike previous efforts, delved into non-recurring facilities and ground support equipment costs. The exercise was especially useful in understanding historical cost data.
- SAGE (2004): This model was a bottoms-up model (unlike top-down models to date). The exercise was especially useful in understanding levels of detail appropriate in different decision making phases.
- AATe (2002-2003): This model added more details to inputs, with an emphasis on supporting decision making when architecting potential space transportation systems. The model was used in many NASA studies addressing the direction for what might follow the Space Shuttle.
- AAT (1998-2002): This model was a prototype for calculation methods that would be used in future operations cost models for space transportation systems.
- Vision Spaceport Partnership (1998-2000): This model significantly advanced operations cost modeling methods. A comprehensive set of technical characteristics (inputs), beyond just propulsion, were related to a recurring launch site operations effort and cost (outputs). Also, some programmatic, non-technical characteristics were explored.
- Launch Operability Index (LOI) tool (1992): This model first used MS Excel to provide a graphic user interface and a calculation method to generate an operability index for propulsion sub-systems. The index was a relative measure of the operability of a propulsion system.
Papers & Presentations:
- Russell Rhodes, Timothy Adams, and Carey McCleskey, "Space Transportation System Availability Requirement and Its Influencing Attributes Relationships (.pdf)", SpaceOps 2008 Conference, hosted and organized by ESA and EUMETSAT in association with AIAA
- Dr. Alex Ruiz-Torres, Edgar Zapata, Marcella Cowen, "Modeling of Turnaround Operations for Next Generation Space Transportation Architectures (.pdf)," International Journal of Industrial Engineering, 2006
- Dr. Alex Ruiz-Torres, Edgar Zapata, Dr. Kazuo Nakatani, Marcella Cowen, "Knowledge Based Representation and Operations Assessment of Space Transportation System Architectures (.pdf)," Journal of Knowledge Based Systems, June 2006
- Carey McCleskey, NASA KSC, "Space Shuttle Operations and Infrastructure, A Systems Analysis of Design Root Causes and Effects, NASA TP-2005-211519 (.pdf)," April 2005.
- Dayana Cope, Dr. Mansooreh Mollaghasemi, Assem Kaylani, Dr. Martin Steele, Dr. Alex Ruiz-Torres, Marcela Cowen, "An Integrated Estimation and Modeling Environment for the Design of the Orbital Spaceplane (.pdf)," Winter Simulation Conference, 2004
- Edgar Zapata, Dr. Alex Ruiz-Torres, "Space Transportation Operations Cost Modeling and the Architectural Assessment Tool - enhanced (AATe) (.pdf)," International Astronautical Federation, October 1999