THE SMART TRICK OF AMBIQ APOLLO3 THAT NOBODY IS DISCUSSING

The S-IVB also continued to thrust at a low level by venting gaseous hydrogen, to keep propellants settled of their tanks and forestall gaseous cavities from forming in propellant feed strains. This venting also managed Harmless pressures as liquid hydrogen boiled off during the gasoline tank. This venting thrust quickly exceeded aerodynamic drag.[