NASA's Road Maps for both Launch and In Space Propulsion call for the development of non-toxic, monopropellant reaction control systems to replace current state-of-art hydrazine. The Orion Multi-Purpose Crew Vehicle capsule with twelve 160 pound force (lbf) hydrazine monopropellant thrusters and the Orion Service Module with eight 100lbf NTO/MMH auxiliary propulsion thrusters are obvious insertion candidates. Additionally, the Commercial Crew and Cargo spacecraft have also demonstrated the need for 100lbf class attitude control thrusters with quantities comparable to Orion. Hydrazine replacements, including HAN- and ADN-monopropellants, combust at higher temperatures making them incompatible with current Inconel 625 thrusters used in 100lbf engines. In addition, Orion MPCV models indicate when current thrusters are fired during re-entry, the extra thermal loads of re-entry may exceed the operating envelope of Inconel. In support of NASA's goal to replace hydrazine and the need for higher performance 100lbf class engines, Plasma Processes proposes to design, fabricate and test a 100lbf thruster with emphasis on non-toxic propellant, increased performance, ease of manufacturing and cost reduction.
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