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Accurately Estimating Class C Spacecraft Bus

Earned Value Management & Hardware Track

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EVM&HW-7 Thomas Paper Spacecraft Est Class A vs C


This paper quantifies the cost and explanatory technical differences between Class A and Class C space vehicles, both of which are often included in space cost databases. This effort was completed by the Air Force Cost Analysis Agency (AFCAA).
MIL-HDBK-343 defines Class C space vehicles as vehicles with a mission that has low complexity, short life, small size, short schedule, and non-critical launch time. Class C missions are typically thought of as “demonstration” programs. In contrast, the mission definition for Class A space vehicles is high priority, long life, high complexity, and critical launch time. This presentation discusses the technological and schedule requirements which drive the cost difference between the classes, and therefore a need for Class C specific cost estimating and risk analysis methodologies.
This study provides a viable starting point for further research into the use of Class C data in an comprehensive spacecraft database and its potential impact to specific cost estimating methods and analysis. Investigation focuses on the spacecraft bus and excludes mission specific payloads. Various cost drivers are identified that are primarily caused by the class of spacecraft bus, such as management oversight, redundancy, power, parts and schedule. Metrics are presented for the Class A and Class C spacecraft bus, including average weight, power, design life, and cost. Data sources for the study included the Air Force, NRO, and NASA programs. A summary of findings is shown in the following table:


Duncan Thomas
Duncan D. Thomas serves with the Air Force Cost Analysis Agency (AFCAA) as Technical Director to the Space Programs Division. In this position he is responsible for all data collection, normalization, research, model development, and estimating standards for Air Force space cost estimating. Prior to this, Mr. Thomas served as Chief of the Space Programs Division at AFCAA.
Mr. Thomas has been involved with cost analysis for over 18 years beginning as an intern and junior analyst for three years at Northrop Corporation, junior/mid/and senior analyst for 12 years with Tecolote Research, Inc., two years as Manager and Chief Scientist of the Cost Estimating Branch of MEVATEC Corporation, and the last five years with the AFCAA Space Division. Major program estimating and cost research efforts include the Air Force Follow-on Early Warning System (FEWS), US Army Theatre High Altitude Area Defense (THAAD) and RAH-66 Comanche helicopter, and research for Tooling for Composite Parts (presented at the 33rd DoDCAS). Mr. Thomas has a Bachelor of Science in Applied Mathematics from the University of California at Los Angeles

Meghan Connelly
Meghan Connelly is a cost analyst for Northrop Grumman IT – TASC and is currently providing cost support for the Air Force Cost Analysis Agency (AFCAA). Miss Connelly has over two years of experience working for Intelligence Community and Department of Defense customers, performing cost estimating, risk analysis, and model development on various Automated Information Systems (AIS)/Space programs. Miss Connelly has a Bachelor of Science in Computer Information Science from the University of Pittsburgh.

Greg Hogan