A pump system for loading fluid into a tank onboard a translating aircraft includes a substantially rigid tube member having a diving device on the distal end of the tube member. The multiple readwrite circuits are organized into a bank of similar stacks of components. A relative rotation between the screw plunger and the handle about the longitudinal axis is restricted, and a relative rotation between the cartridge and the cover about the longitudinal axis is enabled within a predetermined rotation angle and restricted otherwise. The spring biasing force closes the valve member and shuts off the flow of plastic once the mold cavity is filled with the requisite amount of plastic material.