The historical background and characteristics of the experimental flights of ion propulsion systems and the major ground-based technology demonstrations are reviewed. The results of the first successful ion engine flight in 1964, Space Electric Rocket Test (SERT) I, which demonstrated ion beam neutralization, are discussed along with the extended operation of SERT II starting in 1970. These results together with the technologies employed on the early cesium engine flights, the applications technology satellite series, and the ground-test demonstrations, have provided the evolutionary path for the development of xenon ion thruster component technologies, control systems, and power circuit implementations. In the 1997-1999 period, the communication satellite flights using ion engine systems and the Deep Space 1 flight confirmed that these auxiliary and primary propulsion systems have advanced to a high level of flight readiness.

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Ion Propulsion Development Projects in US: Space Electric Rocket Test I to Deep Space 1

Analyses were conducted to examine ion thruster scaling relationships in detail to determine performance limits, and lifetime expectations for thruster input power levels below 0.5 kW. This was motivated by mission analyses indicating the potential advantages of high performance, high specific impulse systems for small spacecraft. The design and development status of a 0.1-0.3 kW prototype small thruster and its components are discussed. Performance goals include thruster efficiencies on the order of 40% to 54% over a specific impulse range of 2000 to 3000 seconds, with a lifetime in excess of 8000 hours at full power. Thruster technologies required to achieve the performance and lifetime targets are identified.

/pdf/scaling-of-ion-thrusters-to-low-power-2w8avvmale.pdf

Scaling of Ion Thrusters to Low Power

The historical background and characteristics of the experimental flights of ion propulsion systems and the major ground-based technology demonstrations were reviewed. The results of the first successful ion engine flight in 1964, SERT I which demonstrated ion beam neutralization, are discussed along with the extended operation of SERT II starting in 1970. These results together with the technology employed on the early cesium engine flights. the Applications Technology Satellite (ATS) series, and the ground-test demonstrations, have provided the evolutionary path for the development of xenon ion thruster component technologies, control systems, and power circuit implementations. In the 1997-1999 period, the communication satellite flights using ion engine systems and the Deep Space I flight confirmed that these auxiliary and primary propulsion systems have advanced to a high-level of flight-readiness.

/pdf/a-synopsis-of-ion-propulsion-development-projects-in-the-ncgmfz47cf.pdf

A Synopsis of Ion Propulsion Development Projects in the United States: SERT 1 to Deep Space I

Future missions, both station keeping and primary electric propulsion, will require multiple thruster restarts after periods of inactivity from a few hours to over one year. Although not a part of the original SERT II (Space Electric Rocket Test) flight objective, the opportunity to demonstrate multiple cathode restarts in space became available following completion of thruster running. Both neutralizer and main cathodes of each flight thruster have been restarted repeatedly following storage periods up to 490 days. No deterioration of cathode heaters has been noted nor has any change been required in starting voltages or currents.

SERT II Hollow Cathode Multiple Restarts in Space

5 "Space Shuttle Phase B System Study Final Report, Part II, Technical Summary," Rept. MDC E0308, June 1971, McDonnell Douglas Corp., St. Louis, Mo. 6 Orton, G. F. and Schweickert, T. F., "Space Shuttle Auxiliary Propulsion System Design Study—Phase A, Requirements Definition," Rept. MDC E0603, Feb. 1972, McDonnell Douglas Corp., St, Louis, Mo. 7 Herr, P. N., private communication, April 1973, NASA Lewis Research Center, Cleveland, Ohio. 8 Kelly, P. J., "Space Shuttle Auxiliary Propulsion System Design Study—Program Plan," Rept. MDC E0436, July 1971 (Revised Dec. 1971), McDonnell Douglas Corp., St. Louis, Mo. 9 Anglim, D. D., Bruns, A. E., Perryman, D. C., and Wieland D. L., "Space Shuttle Auxiliary Propulsion System Design Study— Phase C and E Report, Storable Propellants RCS/OMS/APU Integration Study," Rept. MDC E0708, Dec. 1972, McDonnell Douglas Corp., St. Louis Mo.

Development of a 5-cm Flight-Qualified Mercury Ion Thruster

Prototype auxiliary propulsion subsystem with isolated single tank propellant feed system and 5-cm-diameter ion thruster

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A. J. Weigand

Papers

Status of a five-centimeter-diameter ion thruster technology program