Reliant Panther SSTO
by histalonia
uploaded 2017-05-29
(updated 2017-07-05)
stock spaceplane
#Panther #mk3 #cargo #SSTO #mid

Mid Tech Cargo SSTO for career mode. Able to build and fly with just level 2 buildings.

On orbit delta V of 300-400 m/s. Costs 5400 per flight for fuel.
Highest tech needed is tech 7 Heavy Aerodynamics for MK3 cargo bay.


  • Holds up to 10 tons of cargo. Try and keep liftoff weight at 100 tons or less.
  • For refueling missions there is a small docking port on the belly.
  • For other missions, remove the fuel tank in the cargo bay and add your own cargo attached to a docking port in the cargo bay. Add struts if needed to secure long or heavy cargos.
  • For reentry orbits higher than 90km, add a cooling radiator on the forward bulk head to keep the probe core cool. Or alternatively move the probe core to the rear bulk head.


  • Type: SPH
  • Class: spaceplane
  • Part Count: 93
  • Pure Stock


Set brakes, close doors, set throttle to 30%, and set SAS. Stage to start jet engines. Release brakes, then at 15 m/s use left shift and throttle up to 100%


Accelerate to 131 m/s then flare.

Climb at 17 deg to 2500m
Level to 10 deg and lock SAS
at 3500m stage reliants
at 10000 m stage terrier and time accelerate
at 38000 m switch SAS to Prograde
Abort to shutdown Reliants
Circularize at 74km or higher

Note, when locking SAS, have the nose about 5 degrees higher than your target pitch angle.
The spaceplane is a bit nose heavy. That is mostly due to the liftoff weight.
At 2500m, once you get the SAS set to a pitch angle near 10 degrees let the plane fly itself.
Its real important not to make many corrections, set it close and let it fly.
Most small corrections can be done on orbit or above 45000m.

Rentry Checklist

  1. Make sure batteries are mostly charged.
  2. Switch Panthers to Dry mode. Make sure they are activate.
  3. Pump fuel from both large tanks to forward rocket tank. Target level is 50% - 70% full. You can fly it home empty, its just tougher to control, and you won’t have RCS.
    You may also pump all 4 of the side liquid tanks into the nose liquid tank if you are low on rocket fuel, just keep the side tanks balanced.
  4. Keep a small amount of fuel in the smaller tail rocket tank for your RCS thrusters to continue to function.
  5. Verify Reliant engines are deactivated. (Abort key toggles them)
  6. Perform the deorbit burn.
  7. Close cargo bay doors.
  8. Deactivate tail engine.

Deorbit burn

When first in range of Crater Rim tracking station, burn retrograde until periapsis is 15km. This assumes a 75km circular orbit.
Turn SAS to prograde after the burn.


Stall speed is pretty low when empty, about 55 m/s.
Without SAS on, the plane will slowly climb.
Once on the ground keep the nose down until the brakes bring you below 20 m/s.

A stock aircraft called Reliant Panther SSTO. Built with 93 of the finest parts, its root part is mk3CargoBayM.

Built in the SPH in KSP version 1.2.2.

July 4th 2017 Update. Lowered front gear so its easier to land. Takeoff speed is now 131 m/s vs 128 m/s.

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