This paper presents a description of the Saturn S-IVB stage and aft interstage weight and balance system. This system is used to fulfill the contractual requirements for determination of dry stage and aft interstage mass characteristics for use in weight control and in-flight trajectory analyses.

Special emphasis is given to the development of the weighing techniques and the design considerations required to obtain optimum system accuracy. These areas include: The “Glide-Aire” jack support, the flexural pivots, mechanical connections and weigh system instrumentation.

System evaluation tests run to determine acceptance of the weigh system operational features and test results establishing system accuracy are explained in some detail with a graphical presentation.

In conclusion, actual data from two S-IVB stage weighings are presented to show a system capable of being repeatable to within +/-0.04 percent. Perhaps even more significant is the high confidence shown during the qualification testing that this system is capable of +/-0.05 percent accuracy.