Akatsuki’s propulsion system

Akatsuki’s propulsion system
Akatsuki’s propulsion system Schematic of Akatsuki’s propulsion system, showing how the helium pressurant (GHe) is conducted to the hydrazine and oxidant (MON3) tanks via pressure regulators and valves. The cause of the pressurization failure during the 2010 insertion burn is the fuel-side check valve CV-F, which did not allow sufficient helium flow, and in turn restricted the fuel supply to the orbiter main engine OME. Note in this dual-mode propulsion system the hydrazine (N2H2) supply feeds various small thrusters AB, AT, and T, as well as the main bipropellant engine. Various other valves, filters (FLT), and test points (TP) are shown. Note also the location of the pressure transducers (P-1 to P-4), which allowed the failure to be diagnosed. JAXA