S-IVB Second stage
S-IVB stage is the improved S-IV stage from Saturn I for Saturn V. S-IVB stage for Saturn IB is developed by modify Saturn V S-IVB.
- Diameter : 21ft 7in (6.6m)
- Height : 58ft 4in (17.78m)
- Weight(dry) : 23000lb (10.43ton)
- Weight(loaded) : 253000lb(114.76ton)
- Burn time : 7.5min approx.
- Manufacturer ：McDonnell Douglas Astronautics Co. Huntington Beach, Calif.
Fundamentally, systems were same as S-IVB 500 series used for Saturn V. In appearance, the form of Auxiliary Propulsion System is different. And, the number of the sphere helium tank being installed around the J2 engine was fewer.
Aft Interstage Assembly
This is composed of the panel of stringer-stiffened aluminum skin panels. When S-1B jettison from S-IVB, Aft Interstage remain with S-1B. Then four retrorockets located on Aft Interstage were used for separate between S-1B and S-IVB.