Date of Award


Document Type


Degree Name

Master of Science


Department of Operational Sciences

First Advisor

Gregory S. Parnell, PhD


The Air Force has a requirement to quantify the force enhancement effects of military space systems, but no methodology currently exists for the measurement of their contribution to air combat outcome. This research examines the Global Positioning System GPS and models its influence on air-to-ground combat. The decision analysis technique of influence diagrams is used to identify the effects of GPS launch decisions and constellation size on the navigation accuracy available to air combatants. The effect of accuracy variations on combat outcome is shown by using a value tree to identify the affected campaign Measures of Effectiveness. The study reveals that the use of GPS for navigation and weapons guidance results in a significant increase in sortie lethality that depends on the actual probabilities of survival, engagement, and kill for various weapon, platform, and target combinations. Also, the simultaneous loss of several GPS satellites is shown to have only a moderate time-averaged effect on navigation and combat outcome in the Northeast and Southwest Asia theaters. The methodology presented can be adapted to the study of other military space systems.

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The author's Vita page is omitted.