KerbalX

Details

• Type: SPH
• Class: ship
• Part Count: 240
• Pure Stock
• KSP: 1.11.0

Stats

• Total KER D-V: 8,398m/s

• NERV D-V (laden): 7,921m/s

• Mass: 360t dry/705t wet

• EC storage: 9.8k

• Monopropellant: 1t/270u

• LqdFuel: 350.34t/70,068u

• Oxidizer: 211.8t/42,372u

• Xenon: 0.306t/3,060u

• Funds to assemble in orbit: 4,937,317

• Crew: 5

• Mission time: 10y 368d (~9h realtime)

Description

The complete ship I used to conquer the venerable Jool-5 challenge! My video submission can be found above, but it’s long, so I’ll give a text run-down of everything here.

Overview

This is a modular vessel, consisting of five main components assembled and fueled in LKO over eight ultra-heavy lifter launches. These components include:

• The command section, consisting of the cockpit, a service bay containing extra lander fuel and the ion-powered Bop-Pol lander, the Tylo-Vall lander, some fuel, and a docking node for the Laythe spaceplane lander.
• The drive section, consisting of three MK3 liquid fuel fuselage stacks, providing for nine NERVs that will be used to maneuver around in and return from the Joolian system.
• The interplanetary boosters, two Rhino engines and their accompanying massive fuel stacks. These double-dock to each side of the drive section to provide the kick for our initial trans-Jool injection and subsequent deep-space course corrections.
• The Laythe spaceplane, a questionably functional RAPIER lander designed specially for Laythe.

Notes

• I used MechJeb when flying this craft, but it’s not a requirement.
• As aformentioned, specially designed ultra-heavy lifters are needed for the assembly process, which aren’t shown here. Some of the ones I built weighed in at over a megaton!
• This craft completed the challenge on level three, meaning that one unique Kerbal went to each moon and returned safely to Kerbin. Science, mass and other factors were not considered.
• Feel free to dissect my design and use it as inspiration, but (obviously) don’t plagiarize it.

Mission Profile Part 1 - Orbital Assembly

• Launch one: The command section. Just ditch this one in a standard equatorial parking orbit.
• Launch two: The drive section. I recommend you launch it dry. Dock it to the command section.
• Launches 3-5: Fueling launches, to fill all the MK3 tanks. Simply bring up some full MK3 tanks, dock to one of the side ports, and pump everything over.
• Launches 6-7: The interplanetary boosters. These double-dock to the sides of the drive section - using AutoStrut is highly recommended, although I got away without it.
• Launch 8: The Laythe spaceplane, which docks to the top-rear of the command section.

Mission Profile Part 2 - Flight

• Wait for a Jool transfer window, plot a burn, and light up the Rhinos. Their TWR should make the burn trivial; once you’re on an escape trajectory, plot and perform a plane change to match Jool, followed by a course correction to encounter Tylo with a PE of about 30km. When the transfer boosters run dry, ditch them as close to Jool as possible before firing up the NERVs.
• Brake directly into Tylo orbit. Decouple the Vall-Tylo lander from the command section and use RCS to move it to the side before reconnecting the cockpit to the rest of the craft; land on Tylo and ascend, ditching everything but the core tank and engine in the process. Dock the lander to the nose of the cockpit. Plot and execute a transfer to Vall.
• After capturing into Vall orbit, refuel the lander from the dedicated tank in the service bay. Undock, land, and return. Transfer any remaining liquid fuel to the drive section before ditching the lander.
• Eject the Bop-Pol lander from the service bay. Burn prograde at periapsis to eject from Vall’s SOI; once in a Joolian orbit, perform a plane change to match Bop, followed by a standard transfer. Not the most efficient method, but the ion drive has crazy D-V, so it doesn’t really matter.
• Capture into Bop orbit, wait for the batteries to recharge if necessary, then land. I assure you the ion drive has more than enough thrust and juice to touchdown safely. Wait for the batteries to recharge, then ascend, and burn prograde at periapsis to eject from Bop. Match planes with Vall, transfer/capture, and refuel from the mothership.
• Repeat the above two steps for Pol.
• Once you return to Vall orbit, burn for a Laythe transfer and subsequent aerocapture maneuver. This’ll take some quicksaves to get right, but it’s possible.
• Launch, land, and return the Laythe spaceplane. Drain any remaining LF from the spaceplane and ditch it in Laythe orbit.
• Eject the mothership from Laythe orbit into an elliptical Joolian orbit with a low-ish periapsis - we want to take advantage of the Oberth effect to cheapen our return burn. Make sure to lower your apoapsis to below 15 million to avoid any unplanned Laythe gravity assists - which can and will sling you out of the Joolian system.
• Wait for a Kerbin transfer window and execute a trans-Kerbin injection burn. Capture propulsively into LKO - which should take all of your remaining fuel - and send up a retrieval ship for the crew to conclude the mission!