The Hydra-70 uses small solid rocket motors, which are produced in large numbers. It is used by all branches of the US armed forces and those of several other countries. A research and development program was initiated in 1994 which had the objective of improving the quality of the motors. The motors use solid fuel grain and the effort reported in this paper focuses on providing motors with higher reliability in terms of performance and safety, and at the same time achieving a significant reduction in inspection costs.
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