Passive suppression of pogo on the space shuttle

A qualitative assessment of the tendency for pogo instability of the shuttle vehicle in the absence of suppression devices, and the effectiveness of two passive suppressors (the compliant accumulator and the resistive accumulator) in counteracting any tendency toward instability is provided. In addition, the relative effectiveness of three suppressor locations (the low pressure pump (LWOP) inlet and discharge and the high pressure pump (HPOP) inlet) is also evaluated. The primary conclusion of the study is that effective pogo suppression, with passive devices, can be accomplished at the HPOP inlet location but not at the LPOP locations. Other conclusions are drawn regarding the relative effectiveness of the two accumulator types and with respect to tentative accumulator design requirements. Finally, a number of recommendations are made regarding future studies.