Technology and application aspects of applied field magnetoplasmadynamic propulsion

Currently available or realizable applied field magnetoplasmadynamic (AF-MP D) thrusters operating in the power range 5-100 kW appear to be excellently suited for orbit change and stationkeeping (drag compensation) of large sa tellites because of their high specific impulse, sufficient thrust, and com pact geometry, They were developed to considerable maturity almost 20 years ago, but have not yet been used in space because of the lack of missions, appropriate power, and qualification. There is evidence that these engines cannot be operated realistically in the laboratory, mainly because of the h igh vacuum needed to exclude unknown environmental interaction with the plu me, even at very low vacua, A space experiment is needed to provide proof o f I-sp and efficiency. The International Space Station now provides the opp ortunity to qualify the engine in space. This paper describes the applicati on potential, performance characteristics, and technological status of the AF-MPD thruster, remaining application issues to be resolved, and a space e xperiment proposed to operate and investigate the engine under space-flight conditions.