Yvonne Madelaine Claeys Brill was a Canadian-born American aerospace engineer rocket scientist who pioneered the electrothermal hydrazine thruster. She named it hydrazine resistojet. Resistojet is a strategy of spacecraft propulsion that presents thrust by heating a non-reactive fluid. Yvonne Brill patented her propulsion program for satellites in 1972. She been given U.S. For the final twenty decades of her existence, Yvonne C.