Superfluid experiment in the zero gravity state was performed with a cryostat aboard a sounding rocket S-520. The observation of dynamic behavior of liquid helium (He II), the verification test of a porous-plug phase separator with a controlling heater, the investigation of thermal behavior of superfluid thin film or of a superfluid heat pipe, and the noise test of a cooled FET pre-amplifier for IR detectors were performed. The experiment showed that the initial bulk fluid motions rather quickly damped and a stable liquid containment in the cryostat was realized, and that a very good temperature uniformity was attained throughout the vessel. The porous-plug was found to work as good as the prediction for the zero-g state. The adsorbed film became thicker in the reduced gravity state than on the ground.
