In the era of cryogenic propellants with high specific impulse; under microgravity situations, long-term storage and higher energy thruster management are highly needed. As methane is a reasonable cooling membrane for radiation and ablation chambers so high LOX/LCH4 combustion efficiency and reliable spark ignition to be achieved to develop a methane engine. To maintain the thermocouple system in the spacecraft and to prevent outer harmful radiation in space, the respected agencies may use thick-walled propellant containers with high pressure. To check the feasibility and effectiveness of a subcooled cryogenic propellant, a combination of pump depressurization as active cooling and liquid choke evaporation as passive cooling has been proposed and analyzed.