KerbalX

Description - Updated to KSP 1.8.1

Has science gone too far?! The Niyaama SSTO has been pushed to new boundaries, with this V3 variant capable of taking 108-tons; or 3 orange-tanks worth of payload to LKO with 2800m/s dV remaining. This is enough delta-V to take the payload to the Mun, offload and return. 36-ton payloads (single orange tank) can be taken with 4300m/s dV remaining.

An exercise was conducted to see how far the Niyaama airframe could be pushed without bringing drastic changes. Multiple iterations, and many hours of testing have resulted in the Niyaama V3 variant, which is the most refined version of this design by far. While the tandem gull-wing design remains, multiple changes have been made, which include, but are not limited to:

• Replacement of multiple radial tanks with MK3 tanks and adapters,
• Ramjet replaced with an additional Nuke,
• Four additional Rapiers to help with performance,
• Cargo bay now opens downward to make offloading easier, nose gear moved
• Batteries and reaction wheel assemblies moved and hidden in the rear
• RTG added for backup electrical power,
• Big-S wings added in the middle fuselage,
• Wing angle-of-incidence adjusted to reduce drag,
• Left-rolling tendency minimized with a wing panel adjustment,
• Revised part attachment scheme, giving flexbility in swapping cargo bays and & tanks,
• Various fit and finish improvements.

The result is a massive 113-ton increase in takeoff weight over the Niyaama V2 (and nearly 164 tons over the V1), yet the craft still remains just as easy to fly, with decent TWR. The part count is almost the same as the V1, so previous users should not expect much change in lag.

Built in the SPH in KSP version 1.8.1

Launch Profile - 108-ton payload

It is recommended to keep precision controls on until 20km altitude. Kerbal Engineer is HIGHLY recommended for the readouts it provides.

• Space to activate rapiers, use rudder inputs to remain centered.
• Lift off at 120m/s, minding the tail. Pitch up to 10 degrees, get a climb, then tap F and maintain level flight below 150m.
• Passing 350m/s, stop tapping F, let the nose come up by itself as you accelerate.
• At 7km, hold F to drop the nose to 5 degrees again, and maintain until 1400m/s. Let the nose come up by itself afterwards.
• Your target is 1500+m/s by 20km, with just over 10 degrees pitch. This is essential for the ascent out of the atmosphere.
• At 20km, tap 3 for NERVs. Slowly bring the nose down to maintain speed, while targeting an Ap above 28km.
• At 28km, press 1 & 2 to switch rapiers and close intakes. Pitch up to 20 degrees and hold. Change velocity readout to Orbital.
• When -ORBITAL- velocity reaches 2070m/s, press 4 to shutoff Rapiers, gently drop the nose to prograde, accelerate.
• At 2150+m/s OR when time to Ap reaches 15 seconds, hit RCS and bring the nose up to 20-25 degrees
• Maintain your time to Ap, use RCS if necessary. Slowly lower the nose to maintain the time to Ap constant.
• As your time to Ap starts increasing, slowly start lower the nose to 10 degrees, then hold this pitch above horizon.
• When Ap reaches 65km, hit prograde and hold. At 76km, shutdown the nukes.
• Use Physics warp for the coast to Ap, since this may take a while.
• Add low throttle bursts of the Nukes using shift to maintain the Ap around 75km.
• Once you are out of the atmosphere, deploy the solar panels and antenna by pressing 8, then circularize at Ap.

You should reach orbit with around 2500 oxidizer remaining, which is sufficient for Mun Landings.

Through testing I found that a shallow profile was more efficient than a steeper one, due to the low drag of the craft.

For a 36-ton payload, the profile is almost exactly the same, though you could cut the Rapiers sooner.

Re-entry from 75km Orbit - tested up to 270 tons craft weight

Use this as a general guide for re-entry purposes:

• Aim somewhere near the old-island airfield, and target to deorbit with a 140-ish m/s burn.
• Pitch attitudes of 10-20 will increase your range, 30 degrees or higher will decrease it.
• It is recommended to keep your pitch below 45 degrees. RCS will provide enough authority above 45 degrees.
• If are stuck above 45 degrees, a quick recovery method is to pitch up past 90 degrees, then down again towards prograde.
• The aforementioned maneuver can be used to quickly slow down if done correctly.
• Pitching down too hard can put you into a spin. If this maneuver is required, go no more than 15 degrees below prograde.
• Correct any roll / yaw motions you may have if you pitch down too much.
• If you enter a spin, set SAS to prograde, activate RCS and you should recover soon.
• In the lower atmosphere, avoid drastic yaw inputs .
• The craft has been tested to 18.4g vertically, however it is recommended to keep the g-meter under the red line.
• Try to land as soon as possible on the runway at 75-90m/s (45-75m/s at 158 tons)
• Hold the nose up as long as possible to help with braking.

For lighter weights, move the aiming point further from the runway, practice makes perfect!

Mun landing general tips

Mun landings can take a bit of practice, so use the quicksave! There is no single best way to land on the Mun, so consider this a VERY general guideline.

• Initially make a small retroburn just enough to lower your Pe to your target landing zone.
• Start on the Nukes, pitch up to control your descent rate.
• At the point where you have to pitch up sharply to maintain your descent rate, consider adding Rapiers.
• Press 5 to toggle the Rapiers on the rear as required. Use them just enough to control your descent.
• RCS is essential during the landing phase, since the craft is quite massive.
• It is highly recommended to retract the solar panels and antenna for landing, as these components are rather fragile.

While landings can be done on Nukes alone, paradoxically, I have found it more efficient to use some of the Oxidizer, as that leaves less total mass to be carried by the Nukes for the return trip, increasing your remaining dV

Minmus landings are far easier, and can be done on Nukes alone. I have not tried other bodies as of yet, but I believe Duna would be a bit more challenging and would require more oxidizer and limited payload.

Other tips and warranty information

• If the craft keeps on sliding/rolling on low-g bodies even with brakes applied, just retract the landing gear!
• Plan your trips accordingly, no refueling facilities included. Towing fees apply for craft that run out of fuel.
• You can swap the side-mounted Mk3 rocket fuel tanks, and the central cargo bays for additional fuel as per your needs.
• Remember to autostrut any compartments that you swap. Insurance not available for craft that break apart.