Powersail High Power Propulsion System Design Study

In order to support the development of high power, thin film photovoltaic solar arrays by the Air Force Research Laboratory Space Vehicles Directorate, the Propulsion Directorate's Spacecraft Propulsion Branch carried out an in-house propulsion trade study and contracted for a propulsion design study with Virginia Tech University. The in-house study assumed a 100 kW array and performed the most in-depth analysis of the forces perturbing the array and of propulsion options to counteract these forces. Due to the 10 year duration of the mission, the recommendation was to reduce propellant mass by utilizing FEEP thrusters with their extremely high (8000 sec) specific impulse. However, due to the low level of maturity of FEEPs at the required power level, the trade study recommended a combination of the Busek BHT-200 Hall thruster and the AFRL micro-PPT for a near-term mission. The Virginia Tech University design study looked at a 5O kW array and provided a more comprehensive look at the entire spacecraft system. Prepared in collaboration with Virginia Polytechnic Institute and State University, Blacksburg, VA.