Green Liquid Propellant Upper Stage Engine for Air Launched Targets

TECHNOLOGY AREA(S): Materials
OBJECTIVE: Develop and demonstrate enabling technologies for a liquid upper stage engine utilizing low-toxicity, non-cryogenic liquid propellants.
DESCRIPTION: The goal of this topic is to develop and demonstrate enabling technologies for an air launch/air transportable liquid upper stage engine. Propellants may be new or existing formulations but must be non-cryogenic, non-toxic, and hazard classification 1.3C or better. Gelled propellants (or other approaches for increased viscosity and reduced vapor pressure) may also be considered but must address rheological properties to show understanding of flow behavior compared to conventional Newtonian propellants. Propellants should be able to meet standardized Insensitive Munitions (IM) test parameters and passing criteria as defined by MIL-STD-2105D and be insensitive to adiabatic compression. Engine design and/or components may also be proposed. Key design parameters and associated components should be identified and demonstrated at a subscale level. One example would be addressing the ignition and combustion process of AF-M315E monopropellant that would allow scale-up of the combustion chamber commensurate with performance parameters stated below. For design purposes, consider an engine with a thrust of 900 pounds-force (lbf) (4000 N), burn duration of 75 seconds, and a volumetric constraint of 50-inch diameter by 110-inch length.
PHASE I: Develop a proof-of-concept solution; identify candidate propellants, engine and/or component design concepts, test capabilities, and conduct initial design trade studies.
PHASE II: Expand on Phase I results by finalizing the engine design, building subscale, heavyweight test hardware, and conducting a hot-fire test to validate the design. The test should show high specific performance with scalability to a high thrust, flight representative engine.
PHASE III: The developed solution should be demonstrated via further engine hot-fire testing. Conduct engineering and manufacturing development, test, evaluation, qualification. Demonstration should include, but not be limited to, demonstration in a real system or operation in a system level testbed with insertion planning for a target program.
REFERENCES: George P. Sutton, "Rocket propulsion Elements; Introduction to Engineering of Rockets" 7th edition, John Willey &Sons, 2001. MIL-STD-2105DUS Insensitive Munitions Policy Update, DTICToxicity of Rocket Fuels: Comparison of Hydrogen Peroxide with Current Propellants; http://www.gulflink.osd.mil/al_jub_ii/al_jub_ii_refs/n50en153/dmattie.htm
KEYWORDS: Upper Stage, Liquid Propellant, Engine, Thrust, Low Toxicity