Saturn II - friznit/Unofficial-BDB-Wiki GitHub Wiki
Background
The Saturn intermediate payload study (1966) intended to create lower-cost launch vehicle based on Saturn V hardware to bridge the gap between Saturn IB and Saturn V MLV. Proposals include using the S-II as a first stage with modified sea-level J2 engines or standard J2's air lit after 'Stage 0' solid booster burn out.
Saturn V INT-20 uses the S-IC and S-IVB, skipping the S-II altogether and optionally reducing the number of first stage engines to compensate for the lower overall mass. INT-21 uses the S-IC and S-II second stage with no S-IVB upper stage. A similar design launched Skylab, given that the orbital workshop was a converted S-IVB stage.
Where source docs refer to an "advanced upper stage engine", which is often assumed to be the conceptual HG-3, this guide uses the BDB RL20-P3 as a drop in replacement.
Tags: Sarnus
Variants
| Variant | First Stage | Second Stage | Third Stage | Boosters |
|---|---|---|---|---|
| INT-17 | MS-II-2; 4-7xRL20 | MS-IVB; 1xRL-20 or J-2T | ||
| INT-18 | S-II | S-IVB | UA-1205 or 1207 | |
| INT-19 | S-II | S-IVB | Minute Man SRBs | |
| INT-20 | S-IC; 3-5xF1 | S-IVB | ||
| INT-21 | S-IC | S-II |
Basic Build Guide
From top to bottom
Upper Stage
- S-IVB with Sarnus-HE2JS-428 "Dnoces" Cryogenic engine
First Stage & Boosters
- Sarnus-SIVB Interstage adapter
- S-II with Sarnus HESL2J-475 "Dnoces Sea Level" Cryogenic engine
- Sarnus SII Interstage
- 0-4x Prometheus-1205 or 1207 SRB (INT-18)
- 4-12x Dioscuri-MGU27A "Perseir" SRB (INT-19)
Saturn INT-17, INT-18, INT-20, INT-21
Saturn Derivatives
Saturn V-A is identical to INT-20 but uses a 2-2 main engine shutdown sequence 61s apart. Saturn V-B/C/D concepts are stage and a half designs, similar to Atlas. The first stage consists of five F1 engines, of which four are jettisoned leaving the single sustainer engine to carry the payload into orbit. The engine fairing can be equipped with parachutes to enable the engines to be recovered. S-IVB stage is added to the V-C for achieving higher orbits and an optional Centaur upper stage for deep space missions. The V-D is essentially a fully upgraded Saturn V with the addition of 4 massive SRBs. Truly a bonkers rocket.
| Variant | First Stage | Second Stage | Third Stage | Comments |
|---|---|---|---|---|
| A | S-IC | S-IVB | ||
| B | S-ID | S-IC tank | ||
| C | S-ID | S-IVB | Optional Centaur (S-V) | |
| D (Uprated) | S-ID (+8m); 5x F1A | S-II; 5x J2S | S-IVB | 2/4x 120"; 156" or 260" SRB |
Saturn V-B