NOT KNOWN FACTS ABOUT APOLLO 3.5 BLUE PLUS PROCESSOR

The S-IVB also ongoing to thrust at a very low level by venting gaseous hydrogen, to help keep propellants settled in their tanks and stop gaseous cavities from forming in propellant feed traces. This venting also managed Risk-free pressures as liquid hydrogen boiled off in the fuel tank. This venting thrust simply exceeded aerodynamic drag.[citati