The costs to acquire space-based missile defense systems are often reviewed by DoD. Issues are raised concerning the cost models used to generate cost estimates for space-based missile defense systems. The Ballistic Missile Defense Organization questions the use of traditional weight-based spacecraft cost models developed by the Air Force Space and Missile Systems Center. The concern is motivated by changes in satellite designs of future systems where smaller but more capable spacecraft are being built. Using weight-based cost models yields lower cost estimates, although the spacecraft are more capable. IDA developed spacecraft functional (engineering and manufacturing) cost-estimating relationships (CERs) at the spacecraft subsystem level using performance and physical characteristics that are not primarily weight-based. We developed nonrecurring (design, development, and test) and recurring (production) CERs for the spacecraft bus, including ground support equipment, and for communications payloads. The CERs show that programmatic aspects, which reflect the requirements and acquisition environments that the satellites were acquired under, have considerable influence on satellite costs.

1. Introduction / 2. Space system fundamentals / 3. Reviewing a cost estimate / 4. Space vehicle cost crosschecks / 5. Common issues in estimating space programs / 6. Resources for space system cost estimation / 7. Recommendations.

NASA is responsible for developing much of the nation's future space technology. Cost estimates for new programs are required early in the planning process so that decisions can be made accurately. Because of the long lead times required to develop space hardware, the cost estimates are frequently required 10 to 15 years before the program delivers hardware. The system design in conceptual phases of a program is usually only vaguely defined and the technology used is so often state-of-the-art or beyond. These factors combine to make cost estimating for conceptual programs very challenging. This paper describes an effort to develop parametric cost estimating methods for space systems in the conceptual design phase. The approach is to identify variables that drive cost such as weight, quantity, development culture, design inheritance and time. The nature of the relationships between the driver variables and cost will be discussed. In particular, the relationship between weight and cost will be examined in detail. A theoretical model of cost will be developed and tested statistically against a historical database of major research and development projects. Cyr, Kelley Unspecified Center ...

This paper examines the estimation accuracy of a group of parametric cost models used for a variety of spacecraft. It reinforces the caveat of model builders that models should not be used mechanically but should reflect changing spacecraft characteristics. Weight, the most widely used independent variable, should be less constraining in the next generation of spacecraft with space-shuttle launching. Spacecraft are becoming cheaper on a per-unit-of-performance basis. In estimating nonrecurring costs, none of the models are generally applicable to any subsystem except structure, but several SAMSO models are useful for estimating total nonrecurring cost. All the models do better in estimating recurring costs. The SAMSO models appear most reliable for the user who lacks detailed knowledge of a program and wishes to base an estimate on such characteristics as weight and maximum array output.

Why have the costs of acquiring space systems been so high? What are the sources of the problems? To answer these questions, RAND researchers examined the sources of cost growth of Air Force space systems and undertook an extensive study of two space systems--the Space Based Infrared System-High (SBIRS) and the Global Positioning System (GPS)--including an evaluation of their sources of cost growth, an assessment of their approaches to technical risk assessment, and an examination of their acquisition policy adaptations and industrial base environments. The researchers recommend independent program assessment for space systems that emphasizes technical and program factors, and a modified organizational structure that maintains cost analyst independence. They also summarize the cost estimating best practices of several other government organizations.