Mechanisms for the Formation of Parasitic Propellant Consumption in an Ablative Pulsed Plasma Thruster

Results of spectroscopic studies of electric discharge stages in the channel of an ablative pulsed plasma thruster (APPT) are presented. The initial stage has been shown to affect further discharge development. Shock surface ionization of the propellant has been found to be the dominant mechanism for “parasitic” propellant consumption of an APPT. The results of experimental studies of the dependence of propulsion efficiency and consumption on the distance between operating surfaces of APPT propellant bars are given.