In rocket engine applications, the requirements for light weight and low inlet pressures have resulted in many pump problems. These problems have included impeller rubbing that resulted in oxidizer-pump explosions; bearing failures caused by high axial and radial thrust; excessive cavitation damage; inadequate suction performance; undesirable oscillations in suction and discharge pressure; impeller blade failures; housing ruptures; stress-corrosion cracking; loss of design fits caused by centrifugal or thermal loads; static-seal leakage; and inadequate retention of the components. Additionally, problems have been encountered wherein the structural and dynamic characteristics of the vehicle were involved with those of the pumping system (i.e., POGO effect upon Titan II and Saturn. The solutions to such problems become highly complex.