An innovative Microwave-Powered Plasma Thruster concept for On-Orbit application is proposed based on its significant ISP magnitude advantages over the electric arcjet thrusters attained by reduction of inherent arcjet energy losses resulting as a consequence of the pinch plasma arc used for heating of the arcjet propellant gases. The proposed approach is based on microwave gas turbine engine ignition/stabilization technology developed by API and tested in component test beds and on a jet engine. This effort has demonstrated the capability on non-resonant plasma generators and has characterized the efficiency and quantified the energy losses; and the results along with the known, high efficiency energy coupling characteristics of microwave plasmas support that a higher efficiency is obtainable. The emphasis of the proposed effort will be to design, fabricate and test a thruster for precise thrust and ISP quantification. API has devised a precision thrust measurement technique suitable for the microwave-powered plasma thruster configuration that can accurately quantify the low-power thruster thrust levels. Data from these results will be used to produce a thruster for a Phase II flight prototype Demonstration Test.
