SSTO S-108 Long Mk4
by Val
uploaded 2015-11-29
(updated 2016-11-01)
stock spaceplane
#Heavy #Cargo #SSTO #Mk3 #RAPIER
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The SSTO S-108 Long Mk4 is a Single Stage Spaceplane Drone that will take 100 t to Low Kerbin Orbit with 200 m/s dV spare for rendezvous.

With it’s very long cargo bay, it is well suited for lifting interplanetary ship and station modules.

The Mk.2 has been redesigned to a pure RAPIER setup and now has full RCS translation and a front external docking port.

It is much easier to fly and has lower time to orbit.

  • When loading cargo, be sure to place the Center of Mass close to the pointy end of the landing gear bay.
  • Use RCS only for translation, not rotation. Then it’ll last much, much longer.
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  • Front external docking port
  • Full translation RCS
  • Propulsion: 16 RAPIERs.
  • Liquid Fuel: 13780
  • Oxidizer: 8580
  • Dry Weight: 77.9 t.
  • Wet Weight: 189.7 t.
  • Max Payload (LKO): 100 t.
  • Max Take-off weight: 290 t.
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  • Type: SPH
  • Class: spaceplane
  • Part Count: 92
  • Pure Stock
  • Built in the SPH
  • KSP version 1.2.0
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Ascent Profile

  1. SAS on, Full throttle, Stage and take-off using full runway length.
  2. Build up speed to 400 m/s at sea level. (Below 300 m)
  3. Pitch up to 15° above horizon.
  4. At 5 km pitch up to 10° above horizon.
  5. At 8 km pitch down to 5° above horizon.
  6. At 11 km pitch up to 10° above horizon, again.
  7. At 22 km switch RAPIER Mode. (Action Group 1)
  8. Pitch down slightly to midway between 10° and the prograde marker.
  9. When speed is 1800 m/s pitch down to follow prograde marker.
  10. Throttle down when AP is at 85 km altitude.
  11. Circularize at AP.
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Descent Profile

  1. 80 km orbit. In Map mode, focus Kerbin and turn camera so KSC is facing towards you right above the Navball.
  2. Time warp until your spaceplane is right behind Kerbin.
  3. Put a maneuver node right where you orbit appears from behind Kerbin on the left side.
  4. Pull the retrograde handle until the maneuver is ~100 m/s dV.
  5. Move the maneuver node until the planned orbit intersects the surface through KSC.
  6. Pull the prograde handle until the maneuver is ~80 m/s dV.
  7. Perform the maneuver.
  8. Turn Prograde and time warp till you enter atmosphere.
  9. Keep nose ~35° above horizon until your speed is around 1500 m/s. (May need to move fuel around to keep stable)
  10. You should be nearing the coast of the landmass where KSC is at 25-30 km altitude.
  11. Nose down 5°-10° below horizon and aim to pass the mountains at 10 km, at 650-750 m/s.
  12. Nose down further, if needed, and aim for a point about half the runway length in front of the runway.
  13. At 200 m, flare and aim for the runway.
  14. Touch down with ~70 m/s horizontal speed and less than 3 m/s vertical speed.
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