A Survey of Monopropellant Hydrazine Thruster Technology.

Since the development of the Shell 405 catalyst for the spontaneous decomposition of hydrazine, hydrazine thrusters have been used almost exclusively for attitude control and on-orbit maneuvering of satellites and spacecraft. This report gives a brief account of the multitude of thrusters ranging from less than 1 lb of thrust to greater than 300 lb of thrust that have been developed for more than 30 applications. Major emphasis, however, is on problems that have been encountered during development or flight. These problems include catalyst bed life, thermal management, material compatibility and valve leakage. It is concluded that in spite of the apparent success and widespread acceptance of hydrazine thrusters, reactor design is still largely empirical, requiring substantial testing to establish performance and life characteristics for each new application. In addition, as longer life thrusters are developed, the problems of catalyst life and material life become more limiting. Recently initiated government sponsored programs aimed at solving these long life problems are described briefly. Modified author abstract