SSCM is a parametric cost model that is the end result of more than 19 years of study at The Aerospace Corporation. Its development was motivated by the observation that traditional cost models, based on larger civil and military space systems, tended to drastically over predict the development costs of modern, smaller satellites (post 1990 and under 1000 kg).
Initiated in 1989 as an in-house study of small satellites and their capabilities, the development of the Small Satellite Cost Model is the result of many hours of data collection, normalization, and analysis. The cost model remains one of the most relevant and credible cost models today for performing cost estimates of small spacecraft.
SSCM employs a parametric methodology for estimation of program cost, and is best suited to the early, conceptual development phase of a spacecraft program, during which time the design is likely to be less mature, and when cost and performance trades can be easily performed. SSCM consists of a collection of cost-estimating relationships, or CERs, which estimate the costs of developing and producing a spacecraft system with the following subsystems:
- Attitude Determination and Control Subsystem (ADCS)
- Telemetry, Tracking, and Command (TT&C)/
Command and Data Handling (C&DH)
CERs were also developed for Assembly, Test, and Launch Operations (ATLO), a combination of Integration, Assembly and Test (IA&T) and Launch and Orbital Operations Support (LOOS), and Program Management (PM)/Systems Engineering (SE). Individual subsystem cost estimates are statistically “rolled up” to yield a cost-risk distribution, which provides the estimator with a range of cost estimates and percentiles.
As with any cost model, SSCM is only as good as its underlying data. To create the first version of the model, the developers relied on an initial database of 10 small missions from the late 1980s and early 1990s. Although this initial release focused on Air Force and Department of Defense programs, the data gathering strategy has been applied to the (proprietary) acquisition of technical and cost information of more than 100 post-1990 Earth-orbiting and planetary missions, spanning Air Force, Defense Department, NASA, civil, and foreign programs. This database includes such diverse missions as AIM, ALEXIS, Coriolis, Dawn, FAST, GALEX, IBEX, Kepler, Lunar Prospector, Mars Climate Orbiter, MESSENGER, MightySat II.1, MSTI-1, OCO, Seastar (OrbView-2), STEP 0-4, SWAS, and THEMIS.
In general, a new version of the SSCM is developed whenever a significant number of new missions are added to the SSCM database. Currently, the model is planned to be released approximately once every two years. This ensures that the model properly reflects the latest trends in cost-efficiency and technology development, with the most up-to-date database of spacecraft buses.