Launch controllers have reached the replenish phase of liquid hydrogen loading operations for the interim cryogenic propulsion stage of the Space Launch System rocket and are continuing operations to load liquid oxygen into the upper stage. Teams are moving into operations to conduct a pre-pressurization test, in which engineers will bring the core stage liquid hydrogen tank up to the pressure level it will experience just before launch while engineers calibrate the settings for conditioning the engines at a higher flow rate, as will be done during the terminal count on launch day. The pre-pressurization test is expected to last about an hour.
