ADVANCED PROPULSION CONCEPTS ROCKET ENGINE TYPES A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site pulsed plasma thruster (PPT) A type of electromagnetic propulsion system that has been used on a number of satellites for station-keeping. The U.S. Air Force's LES-6 communications satellite, for example, had four PPTs each producing about 12 million pulses over the lifetime of the thruster. A PPT works by ablating and ionizing material from a fuel bar (typically consisting of a chlorofluorocarbon such as Teflon) with the current from a discharging capacitor. The positive ions released are then accelerated between two flat-plate electrodes – one positive, the other negative – arranged in the form of two long parallel rails which are connected across the capacitor. Escaping from the spacecraft, the accelerated ions produce a thrust of some several hundred newtons. The capacitor is then charged up again from a power supply and the pulse cycle repeated. Related categories    • ADVANCED PROPULSION CONCEPTS    • ROCKET ENGINE TYPES Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP