The S-IVB also continued to thrust in a reduced degree by venting gaseous hydrogen, to keep propellants settled in their tanks and stop gaseous cavities from forming in propellant feed traces. This venting also maintained Safe and sound pressures as liquid hydrogen boiled off during the fuel tank. This https://mylesdkryf.thelateblog.com/34757181/not-known-factual-statements-about-apollo4-blue-plus