Sarnus S1-B
by gc1ceo
uploaded 2016-11-29
(updated 2017-06-15)
mod ship
#apollo #saturn #sarnus #kane


  • Type: VAB
  • Class: ship
  • Part Count: 57
  • Mods: 2


  • Bluedog DB
  • TweakableEverything

The Saturn I’s success paved the way for the more functional Saturn I-B which was the lifter used for the Apollo 7, ASTP, and Skylab missions and as such effectively began and ended the Apollo program’s manned missions. While it was a very reliable heavy lifter it was also a very expensive one, in comparison to Titan-based launchers, and was retired after the ASTP (Apollo-Soyuz Test Project) in 1975.

The Sarnus I-B is a two-stage heavy lifter derived from my earlier Sarnus I model albeit with a more powerful second stage that makes it more suitable for manned missions. The first stage is the same powerful mover from the Sarnus I which will get the payload well into the upper atmosphere on its own. However the upgraded Sarnus IV-B second stage allows for a greater payload, approximately 14-15 tonnes, and more efficiently completes the first of the ascent and the orbit circularization.

The payload is a Kane-11 CSM that simulates the Apollo 7 payload and weighs approximately 14.5 tonnes. It has been given just enough monopropellent, ablative shielding, liquid fuel, and oxidizer for extended missions in LKO (Low Kerbin Orbit). The spacecraft can be used for docking and rendezvous missions with adequately equipped stations and spacecraft and thus can also simulate the Skylab missions and the ASTP if so desired.

The lack of solar panels is addressed with an array of different fuel cells both for experimental purposes and to act as backups in the event of failure of the service module’s main fuel cell. If your planned missions require extensive use of the SPS engine then I recommend conserving your electric supply as best as you can and remembering that you need a bit of thrust left for deorbit and reentry.

The mission profile is simple enough with the first stage separating somewhere in the middle to upper-middle atmosphere with enough separation motors to safely move the massive spent stage away rapidly. The second stage can be a bit tricky especially in the first few seconds as your time to apoapsis may start to drop just a bit and you may have to re-adjust your angle of attack a bit after the separation. I recommend an orbit between 100km and 150km but some of my test flights have easily made 200-250km. The escape tower should be ejected once you have completely left the atmosphere but there is minimal effect by keeping it during the circularization burn.

Built in the VAB in KSP version 1.3.0.

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