Yvonne Madelaine Claeys Brill was a Canadian-born American aerospace engineer rocket scientist who pioneered the electrothermal hydrazine thruster. She identified as it hydrazine resistojet. Resistojet is a technique of spacecraft propulsion that presents thrust by heating a non-reactive fluid. Yvonne Brill patented her propulsion program for satellites in 1972. She acquired U.S. For the last twenty years of her lifestyle, Yvonne C.