An Evaluation of Green Propellants for an ICBM Post-Boost Propulsion System

Propellant toxicity is a major concern in storing, maintaining, and transporting strategic missiles. Many low toxicity green propellants have been developed which hold the potential of increasing the safety and lowering the operation and support costs of liquid-fueled strategic missile propulsion systems. This study evaluates several green propellants for use in a notional next-generation post-boost propulsion system PBPS. The mission and physical dimensions for this PBPS were defined by the requirements of the current Minuteman III propulsion system rocket engine PSRE. Possible propellants were initially screened in terms of toxicity, performance, and technical feasibility for the PBPS application with a multi-attribute ranking method based on an overall evaluation criterion OEC. Promising propellants were identified, and candidate PBPS concepts were developed and sized for each of these propellants. These concepts were evaluated in terms of weight, cost, and technical risk to determine which concepts, and hence propellants, show the most promise for the application. Probabilistic techniques were employed to explore the effects of uncertainty in the propellant performance and structural weight estimates. The results indicate that high-test peroxide HTP combined with either an ethanol-based nontoxic hypergolic miscible fuel NHMF or competitive impulse non-carcinogenic hypergol CINCH is a very viable propellant solution.