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For want of a really big nail (or possibly a bolt): kerbalism grand tour at hard level

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My previous kerbalism grand tour mission (lucy in the sky with deadly radiations; incidentally, i will refer to that mission a lot, as this mission is its spiritual successor, and most of my design was directly influenced by that experience) wasn't yet done, and i was already looking for the next step. Ok, I made a grand tour with kerbalism, though i did allow some slightly relaxed rules for isru. what next? what could i do for a greater challenge?

first thing to mind was to do a similar grand tour, without relaxed isru. Now, normal kerbalism isru is practically unmanageable. except for duna, everywhere else it takes a large convert-o-tron and 100 electricity/second to produce 10 kg of fuel in a whole day. and in the meanwhile, your crew is still going to get stress and randomly smash components. the weight constraints of all that equipment make this virtually unmanageable. Still, i would like to try that some day, either by designing a ship that can keep together for a few decades while it refuels, or by designing a mission that's supposed to only refuel at duna - well, my previous mission was supposed to only refuel at duna, but it used separate shuttles to reach Moho, Dres and Eeloo. I took a shortcut there. I would like to orbit every planet with my mothership. And using the full kerbalism rules for mining at duna is still going to be a major bother.

But I don't feel ready for that mission. it's going to take a lot more adaptation for long term missions. I must also check if the resources needed are actually available; in particular water and nitrogen are very hard to find.

The second idea was spurred by the success of the Dolphin return vehicle. 15 km/s of deltaV on ions, supplies for 3 kerbals for 3 years - those could be stretched easily, food is light - it returned from Eeloo in less than one year and it did drive a small lander on the moons of Kerbin. So I thought, hey, I could make a mission based on that! Instead of a huge gigantic spaceship with greenhouses and mining rigs, a small compact mission for a minimalistic grand tour. No more greenhouses, just a few tons of packed food. No more giant solar array, just a handful of rtg. no more 400-ton radiation shield, just a fuel tank to provide shade. ion engines and a few small landers. and while i am there, i can run a geological survey and check if there are water and nitrogen in the right places for the next mission.



Part 0: How the mission is planned

0.1) Picking up additional challenges


So, the original plan was


Mission: perform a grand tour with kerbalism. the mothership must orbit every planet. No isru is allowed.

It sounded easy enough. and as I am always looking for a challenge, if something sounds easy I will start adding requirements, until the mission becomes challenging, then hard, then OMG HOW AM I EVER GOING TO DO THIS STUFF???

Ok, first additional challenge: this time I will actually land a kerbal on every planet. the previous time i couldn't, because the radiations on the inner moons of Jool would have killed any who attempted to visit all three. This time I discovered how to enable the radiation decontamination, which actually removes radiation damage. So I can land someone at laythe, move away, heal, then land on vall, and then tylo. sounds feasible.


Mission: perform a grand tour with kerbalism. the mothership must orbit every planet. No isru is allowed. One kerbonaut must land everywhere

but wait, why only land one? I'm going to bring the default 4 kerbals. i want to leave a pilot on the mothership - i will rotate vall and jeb. no reason why i should not land everyone else every time. i certainly want a scientist to land on a planet. and an engineer too! and it would only add some weight to the landers.


Mission: perform a grand tour with kerbalism. the mothership must orbit every planet. No isru is allowed. Three kerbonauts must land on every planet

But then, just landing is not particularly inspiring. I already did that. what if I also go scouting around the planet? say, visit multiple biomes? i can do that by just including wheels on the lander. Of course i can't stay long on the inner moons of Jool, so in that case an unmanned rover is acceptable


Mission: perform a grand tour with kerbalism. the mothership must orbit every planet. No isru is allowed. Three kerbonauts must land on every planet and must visit multiple biomes (deploying an unmanned rover is acceptable where radiations do not allow an extended stay).

but hey, what if, instead of wandering aimlessly to the closest biome, i went for specific targets? let's try to visit all anomalies. ok, the mun has a lot of them, and i'm not sure i want to visit them all. i'm also not sure i want to go halfway around tylo just for the cave complex. so, let's just stick with the green monolyth for requirement. so that i will also have to look for it, as its location is random. also, since i will go for discovery, i will use science mode and will try to gather as much science as possible. no specific objective here, just a general principle of trying to include science instruments.


Mission: perform a grand tour with kerbalism. the mothership must orbit every planet. No isru is allowed. Three kerbonauts must land on every planet and must visit the green monolyth, as well as carrying out as much science as possible (using an unmanned rover is acceptable where radiations do not allow an extended stay).

but look, when i choose the new career, it asks for difficulty. i wonder if it does anything to the kerbalism default settings? oooh, it does! radiation shielding efficiency goes down from 90% to 70%, so triple more radiations! Can I even survive laythe like this? The last time i got 60% damage, which would become 180% in this setting, but i spent 3 hours needlessly orbiting the planet. if i squeeze the time hard, maybe i can do it. sounds fun, let's try. And more chances of stuff breaking down in ways that cannot be fixed. longer, more frequent solar storms, but my sun shade should cover that. less resources, but i won't be trying isru anyway. let's do it.

saves/loads not enabled. This, absolutely not. i am still dependent on reloading stuff to correct manuevering blunders. not to mention all the kraken attacks i am expecting to face. so, this feature stays on.


Mission: perform a grand tour with kerbalism. Settings are default for hard level, except for a few minor communication nerfs (requires signal for control, plasma blackout) but with quick saves and reloads enabled (but not allowed to revert malfunctions). the mothership must orbit every planet. No isru is allowed. Three kerbonauts must land on every planet and must visit multiple biomes (deploying an unmanned rover is acceptable where radiations do not allow an extended stay). One command pod must visit all planets.

By this time, what was supposed to be a "small" mission has already been inflated with:

- a much bigger Eve rocket, to account for the crew of 3

- 3 disposable planes (Eve, Laythe and Kerbin, none of the three is recovered to orbit)

- 2 disposable rovers (Tylo and Vall, I won't have the time to use the manned rover)

- a manned lander/rover for the other planets that's much bigger than what it was originally supposed to be.

- a requirement of modular design to complicate engineering.

Ok, now the challenge seems about right. Let's go with it

Part 1: Projecting Nail

To survive radiation storms, i must have the habitats shaded by something else. As I learned in the previous mission, it doesn't have to be all that big, but it has to cover everything. As I want to stick to a simple design, the plan calls for a thin, narrow, long ship, that can be covered by a single S4 fuel tank. No laterally attached crafts or habitats. The name of Nail reflects this simple shape, as well as how this mission is much more unassuming in design than its predecessor

I also grew fond of the idea of a fully modular spaceship, where i would be able to rearrange around the various building blocks. I built with that criteria.

1.1) Habitation module


The mission is supposed to be small, so I won't try to get the full 20 cubic meters per crew member which should be the ideal value. But I must include 4 hitchhicker containers; each one has a radiation decontamination unit, and each one can heal a crew member at a time, so one of those for every crew member. Then i want a lab, to process all the samples i will get. And I want a cupola, because it gives a bonus against stress. Plants are also supposed to give this bonus, but it does not work, so a greenhouse will not be included. A gravity ring also gives a bonus against stress, but it is large and not compatible with a single S4 tank shielding it, so it will not be included.


Technically I can just mount the cupola in line, as nothing in the mod check that there is actually a panorama. But I care for my poor astronauts, so I placed it radially for an unobstructed view. One cupola alone was ugly, so I placed two symmetrically. I also placed some RCS propulsors to help in docking, but I now think I will just save the fuel for EVA. There are some big gas tanks, because i won't be able to get any new. I said no isru, but this says nothing about recycling what you already have, so i included chemical plants to recover oxygen from the waste carbon dioxide. The middling section is food and water containers. in the bottom are electric batteries, reaction wheels, two radiation shields (I won't try to carry 130 again, but a couple are useful) and many rtgs. No solar panels this time; I will just plan for the worse at Eeloo. RTGs are fine as long as I keep them far away from the crew modules

1.2) Engine module


This module will include all the spare fuel for the landers in the sunshade tank, as well as the ion engines and the xenon. Kerbalism gives some very efficient gas tanks, so carrying xenon is even easier than usual. I include the option to discard empty tanks, for some weight savings.



Those pressurized tanks store over 200 tons of xenon, should be enough to give me around 40 km/s.

I did include some solar panels here. The RTGs aren't enough to operate 24 ion engines at 100% power unless I pack a ridiculous number of them, so I decided to compromise. Those panels give me 100% thrust as far as Duna, and going further I can afford slower manuevers.

Do notice the price tag; xenon is really expensive in this game

1.3) Eve sucks Eve lander


My previous - and only - Eve lander, the FU Eve, was huge and riddled with problems. But I learned a lot from it, and I am ready with a new, best, ligher, improved version. The main problems were aerodinamics, so I streamlined those


I fixed the thermal shields so I could get away with 3 instead of 8. I placed them on high towers to keep them away from the center of mass, now the ship is much more stable during reentry. I also made sure to put the parachutes on the discardable towers, a detail that caused me a lot of grieving with the FU Eve. The airbrakes tower is something I learned about from another user, I would expect them to blow up in the heat but they are actually covered enough, and they help decelerate and stabilize.

The two boosters are inclined so that they will push away from the rocket when released, and they need less struts. As the ship is optimized, only two are needed.

I learned to not discard things from the sides because Eve's atmosphere will push it back against the rocket, still the modular design of the main ship made this unavoidable. But at least I made the boosters lower than the ship, for reduced risk of collision. WIth this, I am able to detach the boosters at over 300 m/s, while the FU Eve had to slow down to 150 m/s before stage separation


The design includes a small propeller plane to cruise around the planet. The plane has a hydrogen/oxygen fuel cell for power, and solar panels + chemical plant to recharge the stockpile of hydrogen. It is attached between the second stage engine and the thermal shield; while the rocket will fall down on parachutes, the plane will be detached, and will land on its own. It's supposed to be piloted, but it has an antenna and a command module so it can go remote if needed.

The landing pod on the left is my alternative to ladders. The FU Eve had this ridiculously convoluted ladder, which misaligned during landing and almost left me stranded. I decided to include two cabins at the bottom for the astronauts to exit from. Instead of climbing a long ladder, they can take the elevator inside the ship.

Wait, if there is an elevator inside, shouldn't it have extra mass? NEXT!


While I swore I'd never do that again, I decided to use the last stage as Laythe lander this time too. The size was about right. I hope I can land it upright, but it doesn't look too thin.

The rocket design (12 vernier Cub engines) solves at once two problems: how can i make a lander that won't be doomed by the failure of a single engine (something that was a major problem for the FU Eve, while the Can tried to solve this but got a too low TWR), and how can I make a lander than I can dock on the base. And the docking port on the base let me put the parachute on top, where it should be, and it avoids most aerodinamic problems of its predecessor. The command pod can be detached and attached somewhere else, i hate to add 400 kg to an Eve rocket like this, but i like the modular design. On top I have supplies for over 50 days, two solar panels, and a fuel cell for nights. I was unable to include an electrolysis plant, so the fuel cell is limited by the amount of hydrogen stored. There is enough for a few days, though, which lets me get by for a few planetary nights. I deemed this enough, I plan to only stay on Eve for a few days, on Laythe and Tylo for a few minutes, and everywhere else the pod will be coupled with the rover, which has RTG of its own.

1.4) Rover/lander platform (name to be determined)


Having covered all the worlds with atmospheres, I now need a rover for everywhere else. I need 2000 m/s to land everywhere, but not much more because that would be dead weight. I need a stable base, because I want wheels on it. And this time I'm definitely going to remember to put a decent TWR on it! Oh, and it must be able to couple with the command pod


Not visible in the picture are 4 spark engines underneat the fuel tanks. This allows the lander to survive the loss of any two engines.

For power there are 4 rtg on the opposite side of the robotic arm, for weight balance. Looks a bit clumsy, but it should be pretty stable, and without an atmosphere it won't have stability problems.

I haven't come up with a good name yet. I'm sure I will come up with something once I start using it.

1.5) Disposable planes


I wanted planes for Laythe and Kerbin too, and I decided to do a single design for both.


Instead of keeping the design of the Eve plane (which assumed a lot of sunlight to recharge batteries) I used some rtgs in the cargo bay. That's uncomfortably close to the crew cabin, but those things are supposed to stay unmanned most of the time. I also included a rover arm (i was worried about drag on Eve, it's much more unforgiving) and two small rockets with 100 m/s, just enough for a bit of manuevering and to deorbit on their own.

Again, no name. But they are simple enough, I don't even think I will give them names.

1.6) Tylo descent stage


As usual, whenever isru is not possible, one must include a special stage just to land on Tylo. This time I did the unthinkable and decided to actually attach it to the bottom of my rocket. The advantages of having a rocket with a docking port on the bottom!


This tank should supply 2000 m/s to the main stage, which, in addition to its 3200, should give a comfortable margin. I used 4 darts as engines, mostly because i could stick 4, for redundancy. And I will also be using the Cubs during descent, of course. After the tank is discarder, there is a rover ready to be dropped. Here the operation is going to be complicated, because the rocket is going to land on top of the rover. My plan calls for landing, detaching the rover, doing a short hop - it should take 100-150 extra m/s, within the fuel budget of the mission. But I haven't tested the system, so there's plenty that could go wrong. At least I was careful about the TWR, I learned that lesson.

There are two rovers here, but one is for Vall. they have a seat to bring around a kerbonaut, but i don't expect to use it much. Maybe to collect a surface sample from the closer biome.



And that's all. No mining rig, no Moho stage, no escape capsules. I have a lot of objectives, but still I aim for a simple design.

Edited by king of nowhere
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46 minutes ago, Single stage to ocean said:

How do you activate the radiation decontamination unit @kingofnowhere? Thanks.

there is an option you have to check when starting the sandbox: not really sure how it is in english, but it means "all parts upgrades are applied in sandbox mode"


if you didn't check this option when starting the game, i'm afraid there is no workaround.

alternatively, you can start in science mode, edit the file to give you a few tens of thousand science points, and tech everything manually.

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Part 2: Assembling Nail

The various components of Nail are launched and assembled


2.1) Launching Eve sucks


Launching the Eve sucks on its own fuel would have been too easy, so I made a special launcher to send it to orbit with tanks full. It's quite awkward because the limitation on not attaching stuff underneath the mammoths is quite the problem here. Having a plane attached in the middle, strangely, is not a problem; or at least, not enough of an aerodinamic problem to register on this launcher.


Liftoff! To launch this thing I attached a large mammoth tower at the bottom, and 4 srb at the sides



Liquid fuel boosters separation


Running on the second stage, which comprises a mammoth and the 4 srb


The boosters finally run out of juice and are jettisoned. The final mammoth has enough fuel for circularization

2.2) Launching the habitation module


The habitation module was launched with a single stage mammoth. For all that it looks complex, it's barely 50 tons of payload.


Inside the fairing I included two service probes. They are a slightly refurbished version of the one I brought with the Marco Polonium: they have a claw to grab stuff, a lot of reaction wheels to move it around, and a disproportionate engine. Plus a docking port because the claw does not allow refueling at this difficulty level. They are useful for grabbing parts and moving them around, which I expect I will be doing a lot.


The service probes. I am carrying 2 for redundancy. I later saw fit to include a third one.


Once in orbit, this small RCS stage takes care of docking. I used vernor engines because I could fit them between the fuel tanks and the decoupler. Using engines would have requires a 2.5 m engine, which would have been too big for the task, or a change in diameter which would have messed up aerodinamics.

A thin, long, narrow ship like this requires a lot of autostrutting to avoid wobbling. And autostrutting does not mesh well with kerbalism, resulting in misshapen ships. But I learned by now that those bugs will be reverted between saves and are not fatal, so I'm mostly ignoring them


The ship-scrambling bug strikes already!


First two parts docked successfully

2.3) launching the Tylo descent stage, plus a bunch of rovers


Next is the Tylo descent stage, with the rovers. Since I have room on this one, I also include one of the planes. This thing would be an aerodinamic nightmare to launch, too draggy and in a very complex shape. I actually tried encasing the whole plane in a fairing, but to include the wings it had to be exceedingly large, and the drag was a real killer.

So, since the draggy parts tend to go to the back of the rocket, I tackled this problem by putting them in the back in the first place! I capsize the rocket, put the engines on top on the sides, this way the engines are dragging the offending part behind them and there is no chance of capsizing.


I wonder what would happen to try and launch this thing in real life. It probably could be done, at the cost of reinforcing the trusses to much that the whole thing becomes completely impractical

And hey, this thing actually flew very well! No shacking, no twisting, very stable.


I never noticed it before, but the twin boar engines have a very pretty bluish/purple flame. Perhaps my favourite exhaust. Too bad the low Isp makes them unsuitable as anything but first stage


This module had a small docking module with some Vernor RCS thrusters, just like the habitation module


Docking the various pieces


Nail begins to take shape

2.4) Launching the engine pack


Finally, the engine pack, with the last plane. This is also a very aerodinamically challenging piece, being very large and flat, so I'll use the same strategy of carrying it backwards



I would like to make some witty remark on how this thing should never fly, but words are failing me


booster separation


atmosphere cleared, nose cones separation


I sure hope those exploding are the nose cones, and not my ship



yes, they were the nose cones. The ship is intact

In all this, I am producing quite a lot of orbital debris, of which I take care with the tested-and-true method of deleting them manually from the tracking center.

Ok, it's a bit like cheating. Then again, it's not like it would be actually difficult to perform a small retrograde burn to ensure that those nose cones end up suborbital, before raising orbit again. And for the other rocket pieces, including an okto2 for control and a small engine to deorbit would be trivial. Just a bit of a wasted time. So, as with so many things that can be done trivially with just some expenditure of time, i decided they are not worth my time. I 'll just pretend I have deorbited them manually


Ion engines have a nice blue exhaust. Solar panels are clipping, I will have to fix them with an EVA


And this is what happens when I try to dock the engine module to the rest of the ship without enough autostruts

2.5) Launching the rover base, probes, and various leftover. Assembly complete


Finally the rover base. At this point I realize I am missing an important factor: something to actually detect the anomalies. So I put together a couple of small probes with a rovemate core (the only core with 100% anomaly detection),  an ion engine and a lot of antennas. Being basically spy satellites, I called them get your tinfoil hat.


I also sent a cargo container with a bunch of materials for EVA construction, because I forgot a lot of things: repair kit, EVA experiment kits, docking ports, lights... before that update, I frequently had to scrap whole ships after forgetting some pieces. Now I have the chance to fix them on the spot.


I'm using the reverse rocket for this one too


Docking to Nail


Finally, I run a few calculations and decided i needed additional food, water and oxygen. I launched this additional piece of supply storage


I forgot a docking stage, the service probe is doing its job


Finally, Nail in all its illogic glory. The planes on the side ruin the profile a bit


I plan the trip to last 20 years, so I brought supplies for 30

With this, Nail is ready to start. Of course, since I started assemblying it straight away instead of waiting the Eve transfer window, I have to wait in orbit for over one year...

Edited by king of nowhere
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Part 3: Feeding Nail to the kraken

Before even leaving low Kerbin orbit, Nail is struck by a crippling kraken attack. The engine pack must be scrapped, and the ship rebuilt without ion engines


This screenshot shows the engines throttled up, and active, and with plenty of xenon and electricity, yet not working

3.1) Did you get your tinfoil hat?


Since I have to wait one year to launch for Eve, I may as well use the time to explore the moons of Kerbin. I would like to land there, but I cannot get rid of the airbrakes on the command pod; I must land at Eve first. But I can send a Get your tinfoil hat to scan all the anomalies in the meanwhile. This is actually the first time I really try scanning for anomalies. And hey, it actually works! I never got the hang of it in the past, but that's because i was scanning outer planets where there were no anomalies to be detected.


If those anomalies didn't want to be detected, they should have gotten a tinfoil hat!

It's actually a bit sad. There are so many interesting things on Kerbin and Mun. Then on the other planets there's almost nothing. I'd hope they add more anomalies in the future, but it's a bit late for that. I'm not even sure how long they'll keep supporting this game with the 2 in development and close to release

3.2) The kraken strikes again


After a long wait, it's time to launch for Eve. There is only the little problem of thrust.

Nail is around 700 tons, a third of which are the Eve lander alone. Goddamn planet! It has 24 ion thrusters, and it's hard enough to get electricity for them in the outer Kerbol system as it is. This makes it 48 KN of thrust, accelerating the ship at a breathtaking speed of almost 7 cm/s!!!! The 1000 m/s burn should require 4 hours. And for some reason it ends up accelerating even less, because a continuous thrust over 6 days raised my orbit from 80x80 to 3000x3000 (yes, I know, raising the orbit like that is not particularly efficient. I was going to reload and do it again with proper apoapsis raising, except that i had to remake the ship)


why, why did you have to leave us? You were too young, and your exhaust too beautiful

Until, suddenly, the engines stopped working.

But ok, I can reload the game, it generally fixes this kind of stuff.

I reload the game, and the engines stop working again. At exactly the same time. I reload at a more ancient save, and the engines this time work... for a while, then they eventually shut down again.

I run some tests, the chemical engines also don't work anymore. The rockets are just not functional. And nothing I can do seems to fix this.

I also got the same problem with the get your tinfoil hat earlier, but that time a reload fixed it. Then again, that small probe has a burn time of a few minutes.

Long story short, I was able to ascertain that the problem is the persistent thrust mod. This mod allows me to time warp while using the ion engines. Except sometimes it prevents time warp altogether, and some other time it stops the engines from functioning. After more attempts to fix ( they are the primary reason it took me one month from the end of the previous mission to actually posting the new one), I determined that the only way to make Nail work is to remove the mod.

This, of course, would force me to run a several-day-long burn in real time. No, thanks. Even i am not this crazy.

So I resolve to remove the persistent thrust, remove the engine pack, and remake Nail as a nuclear-powered ship.

The persistent thrust mod is looking pretty bad here, but I want to remember that it allowed me the 6-day burn when Dolphin 3 returned from Eeloo, as well as other very long burns when I was rejoining Dolphin 1 with the DREAM BIG. It has its uses, and I am keeping a copy in my hard drive in case I need it again. But it won't work for Nail.

Edited by king of nowhere
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I would do it in real time b/c I’m a lunatic. Poor you, you have to replace the whole thing. Hope you fix it fast with the new nuclear apparatus

And @kingofrandom, you can change it mid game, just go to homescren,where you see the VABSPH, mission control, etc, press escape, then press settings, then search for “All part upgrades are applied”

And adding more ions and solar would actually increase delta-v b/c of gravity losses.

I bet you can increase speed to 21 cm/s

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Part 4: Goodbye Nail, welcome Bolt

The ion engine pack is removed and swapped for a nuclear engine pack. Moar fuel is added. The ship doesn't look like a nail anymore, so it's now called Bolt


4.1) Plutonium for the plutonium god!


Ion engines are not an option, so I turn to the second most efficient engine, the nuclear one. The overall shape stays more or less the same, i still want something large that I can attach stuff on both sides. This is the result


I kept the same general structure of the engine pack, but I attached 18 liquid fuel fuselages, for a total of 900 tons. They can be discarded one by one as they get empty. now the ship is much bigger and it needs more reaction wheels, i added them to the drop tanks so they can be discarded too when they are no longer needed. I attached the NERVs on the sides with trusses, I already tested this configuration with the flying christmas tree and it works really well to apply engine power while leaving a convenient docking port on the back.


I used 18 NERVs; my target is TWR between 0.1 and 0.15, again based on my experience with the flying christmas three and the marco polonium. more twr would require more engines, and the NERVs are very heavy; too many of them, and I lose the advantage of the Isp. But less engines than that would be too complicated to make fast manuevers.

Now I have to launch this thing. It's over 1000 tons, with a horrible aerodinamics. To begin, I start by putting some detachable nose cones everywhere


For the second stage, i attach some liquid fuel tanks and rhino engines. the awkward shape of the liquid fuel fuselages makes things more complicated. I could look for the mod to swap the engine functionality, but i prefer to not install additional mods unless i really have to. Especially after the bad experience with the ion engines.


For the first stage I use mostly boosters, because even though i am not keeping track of money, i still like to think of this as a somewhat realistic mission, with some limitations about funding. So I use a bunch of clydesdale, until I have enough for the target deltaV. I strap some additional thumpers for extra thrust at liftoff. In the middle there is a liquid fuel tank with a mammoth, to provide gimbaling control




Thumper separation


Dropping the clidesdales. There are a lot of them, this parts get quite messy




Atmosphere cleared, nose cones ejected


Docking with Nail


I swapped out 200 tons of xenon for 900 tons of liquid fuel. It has 5 times less Isp, so I carry 5 times more fuel, it's going to be enough?

There isn't a good way to calculate the actual deltaV of a ship with drop tanks and multiple landers that are discarded after use, but I think of a guideline to at least make an estimate:

1) calculate the deltaV as if you are not going to drop any weight. You certainly have more than that. I have about 400 tons of payload, including the Eve sucks, the fuel for the landers, the habitation module. with 900 tons of fuel it would give me 9000 m/s. Ok, I know i at least have more than that, but it's not terribly informative.

2) calculate the deltaV as if all your dry mass is the dry mass you're going to have in the end. You certainly have less than that. If I keep only the habitation module, the engines and a few tanks i cannot drop, I am left with around 150 tons. I make the calculation with 900 tons of fuel, and it tells me I have 16000 m/s.

So, my actual deltaV is somewhere between 8 and 16 km/s.

Now I make some estimates on how much fuel I'll need... oh, crap!

Kerbin-Eve 1500
Eve-Moho 4000
Moho-Duna 6000
Duna-Dres 2200
Dres Jool 800
all Jool 5000
Jool Eeloo 2000
Eeloo-Kerbin 3000
total 24500

Now, some of that cost can be reduced. I know I can find some gravity assists from Eve to Moho to save some fuel. On the other hand, with low thrust, I'll certainly lose some efficiency. I need at least 20 km/s to even try this grand tour with some hope of success. 30 km/s would be an ideal margin.

So, I need at least twice more deltaV. And because of the way the rocket equation works, I need about 3 times more fuel.

To think I started with the idea of a small mission :huh:

4.2) Fuel for the fuel throne!


For every fuel tank I have, I need 3 more. The most straightforward way is to attach them directly at the bottom of the tanks I already have.

This will quadruple the weight, so I will need moar engines and moar reaction wheels. I want to drop them too, because I'll top at over 50 NERVs, that's 150 tons of mass, it would be overly wasteful to carry them all the time.

So, here is the drop tank project


18 of those will be joined to the 18 exhisting tanks, bringing the total fuel to 4500 tons. This ship is going to be heavier than the DREAM BIG.

Only problem, there are no docking ports on the fuel tanks. Don't worry, we have EVA construction for this. I only need to send up the docking ports


18 docking ports to be used for construction. Must be one of the dumbest things I ever launched. Do notice the ant engine on the side: The bobcat (indeed, any engine big enough to lift this) can only be used twice without maintenance.



bringing all the docking ports in place. 18 is a surprisingly large number when it's work you have to do

Now I have to launch the drop tanks, all 18 of them. To save time, I'd rather avoid 18 launches. Launching 18 tanks all together would be very complicated, I compromise with launching 6 at a times, so I can get away with 3 launches. This time I can use a standard asparagus stack





First stage separation


Second stage separation


Ejecting the nose cones. This time I had the foresight to include sepratrons to kick them out of the way. The fairing is discarded, revealing the Forklift


Third stage separation


After third stage, the rocket is left with the central tank and a rhino to circularize. The rhino can only be turned on twice, so there are also four wolfhounds for manuevering


After rendez-vous, the Forklift is sent to dock to a tank



And it pushes the tank in place, thanks to its powerful RCS system to move in all directions


Assembly goes on


EVA construction is used to get rid of the remains of the hydraulic detachment manifolds; they are heavy and they increase part count


Stacking the tanks require precision, but the Forklift is up to the task

The shakings are still a problem, despite everything being autostrutted. Many times, upon docking a tank, the ship starts trembling and breaks apart. I can always get by with reloading, but in one case a single engine got broken without me noticing. I only discovered it when I saw an unaccounted-for piece of debris on the map. By then it was late to revert with a simple reload, i decided to keep going; one single engine more or less won't make any noticeable difference out of 54.


The broken piece of engine, floating in space

It was a long, grueling task. By now I had around 1000 parts in physics range, so the game lags heavily. The ships are all very big, and they are slow to rotate. The forklift actually doesn't work all that well, having only RCS it cannot fine-tune the thrust, and it is very overpowered when it's not attached to a tank. Plus it wasn't perfectly balanced, so I had to shut down the SAS every time I used the engines. Overall, it was very good at moving in all directions, but nigh-impossible to control (if you are wondering why I saw fit to only use RCS: RCS engines are the only ones in kerbalism without a fixed amount of allowed ignitions. i needed engines for many manuevers, and it seemed a good thing to not have to worry about ingition numbers). And after I finished docking a tank - which required 30 to 60 minutes of real life time - the rocket with the other tanks had drifted away, so I had to rendez-vous again. With a vehicle with poor manueverability.

After the first 6 tanks, I then improved the whole setup. I put more reaction wheels on the Forklift. I included regular engines on it (ant engines, they have over 100 allowed ignitions). And I put a large clamp-o-tron on the front of the main rocket so I could dock it to Nail; no more drifting in space after every tank is attached.

Well, it took over 2 days of real life gaming  (also because my free time is no longer what it was while I was using the DREAM BIG). But the result was good


997 parts, 4840 tons


some of the fuel tanks didn't align perfectly and were docked hapazardly. But apparently it doesn't cause any problem.


Also, I learned to increase environment light so that the ship is always well lit. No more "sorry you can't see anything, but i was manuevering by night"


Now I am, again, ready to start.

There is only one problem: when I devised the ship, it was called Nail because it had a long, thin body with a large, flat head. That's no longer the case, so I need a new name. My brother came to the rescue: "it has a larger head, so it's now a bolt".


I'm not sure...


That's it!

Bolt it is, then.


Edited by king of nowhere
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I have an idea. Instead of rad shielding, you just put all the crew in rad detox and control it with a probe? When coverage is out and you have Kerbals in passenger pods, they can be transferred, you have limited control, then transfer them to cupola for control.*insert Hal-100 reference here*

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Part 5: Eve sucks, but it's not too bad

In the first part of its trip, Bolt reaches the Eve system and deploys the landers. The monoliths are found on Eve and Gilly. Some difficulties were encountered that forced a ship redesign


5.1) "Think of it as a learning opportunity"


It's kinda traditional that, upon launching a large mission, i barely reach the first major destination before realizing i have miscalculated/forgotten something important and restarting fresh. This mission is no exception. Real life space agencies don't have the luxury of reloading halfway through the mission; on the other hand, real space agencies have hundreds of people working on a project full time. Here I am alone, I can forget things.

In this case, what I forgot was an intermediate cruise vehicle.

On the big level, I have the mothership with all the life support and supplies. That's very expensive to move, and should manuever as little as possible. It reaches a planetary's SoI and gets parked there in the cheapest possible way. You do not want to circularize its orbit, it would be too expensive

On the small level, there is the lander. It needs powerful engines to overcome gravity. In this case it also wants to move on the ground. And it's got to burn a lot of deltaV to go up and down from everywhere. So you want it as light as possible. You drop it from low orbit with minimal fuel. You only give it enough fuel to land and take off from Moho, anything more would be wasteful. You do not want to circularize orbit with it, as that would require extra fuel tanks, those would require extra engines, and to move them you'd need extra wheels.

None of those two extremes wants to circularize. For this you need an intermediate vehicle, one that leaves the mothership in high orbit, brings the lander to low orbit, picks up the lander when it returns to orbit, and carries it back to the mothership. In the previous mission, the Diggers had that role. In the previous previous mission (with flying christmas tree) no ship was deputed to that task, but i had isru everywhere, so i could afford to waste fuel.

Here I cannot waste fuel and I didn't have a taxi. And so I found myself having explored Eve, and coming back to orbit, and needing an additional 500 m/s for the command pod to rejoin Bolt. And I didn't have anything that was up to the task.


The command pod emerges from Eve's atmosphere having heroically spared almost 900 m/s worth of fuel. I tried a dozen times, and I could never again make it with more than 500

Oh, I tried to improvise something as a taxi. After all, the point of a big modular design is that it gives you options. And here I had many perfectly serviceable fuel tanks with engines, and service probes to provide control. Seems like a solution. Go service probe!



The engines are not aligned with center of masss, so i must drive this thing very slowly to let the reaction wheels compensate. Why didn't I think to align them?

Well, and why should I have? It's not like this was ever supposed to be anything but a disposable fuel tank

The low thrust of this impromptu vehicle forced multiple passages to slowly brake (aerobraking is not an option; I tried, the atmosphere destroied the ship before it slowed by as much as 5 m/s). Unfortunately, just as the tank was passing behind eve, it lost contact.

Yes. The service probe has no antennas. It gets piloted directly from Bolt, or it uses it as a relay. No, I never imagined that a service probe would have to be sent away from Bolt, unable to use a radio bridge. And I couldn't take one of the antennas from Bolt and paste it on the fuel tank with eva construction because I didn't have an engineer on Bolt.

So, I decided I needed to scrap the mission, and restart equipped with a suitable vehicle, which I called Taxi


It has 4 engines, 3 reaction wheels and 2 antennas for redundancy. It also has 2 life support modules, again for redundancy; I realized, while I was looking for small improvements to make, that the command pod only has one life support, and losing it would end the mission! The small pod didn't have room for a redundant system, but it's going to spend most missions coupled with rover. So I added a couple spares there too. The only other times it will be on its own will be during Tylo and Laythe descent; and in those cases I'll want to quit immediately for the radiations, and I am sure the crew can survive one hour with the life support offline if needed. But it will take some days (at least) to rejoin Bolt, and giving life support to taxi fixes that need. It also has 2 smaller relay antennas to help bridge communications between command pod and Bolt. Or between a Get Your Tinfoil Hat (GYTH for short) and Bolt.

I also made other small improvements to a few more vehicles, like the planes and the rover. None of those is big enough to be worth "before" and "after" pictures, though.

In fact, most of the mission was similar enough, I decided I can keep using the old screenshots for the rest of part 5. So, if in some pictures you see the plane with a rover arm and in others it's not there, that's the reason.

5.2) From LKO to Eve elliptic


Launch from Kerbin and trajectory are normal. I use a Mun gravity assist to save a bit of deltaV. There are a lot of apoapsis-raising manuevers, maybe as much as 10 of them, but it does not present particular problems




Dropping the occasional spent tank


Sending Bill to repair the engines after the final ejection burn


Performing EVA experiments during Mun flyby

The interplanetary trip was mostly uneventful. The sunshade is doing its job. At first I got some radiations passing that I couldn't figure out, until i realized the planes attached radially are far enough that they are not covered. So I run another batch of EVA construction to mount them on top of the tanks, after that no more problems.

On 4/8/2021 at 5:41 PM, Single stage to ocean said:

I have an idea. Instead of rad shielding, you just put all the crew in rad detox and control it with a probe?

I'm doing just that, but it's no substitute for radiation shielding. Detox is very slow, it took several days to lose the few % of radiation damage they took while passing Kerbin's radiation belts. If I did not try to minimize exposure, they would get damaged faster than they heal. Also, detox consumes oxygen.

200 days later, arrival at Eve. The injection burn for 400 m/s takes 8 minutes, longer than one would like but still short enough to have limited losses.



Dropping more fuel tanks. The whole Eve trip costed 800 tons of fuel. It's going to get much cheaper as the ship becomes lighter.

So far, the ship is doing well. The twr proves to be a good compromise between efficient manuevers and light engines. Radiation shielding works, shedding drop tanks works, draining of fuel and life support nominal. The ship is parked into a high elliptic 100x40000 orbit from where it can leave easily. It's time to look for monoliths



Moving GYTH into a polar orbit where it can scan all of Eve


Here is the monolith, near the south pole. If it didn't want to be found, it should have gotten its tinfoil hat!

Time to drop the Eve sucks lander. The placement of the monolith means I will have to run across the whole planet to reach it from my equatorial orbit, it's time to test whether the Eve plane is fit for its task

5.3) Eve landing


The Eve sucks is detached, the heat shield cover is ejected




I made the deorbit burn before extending the shield. I am not sure it can use the rockets with the shield on, tankfully i didn't have to find out

The Eve sucks is better than its predecessor at aerobraking, but still circularize gradually before it can land.



Eve seen from the cockpit of the plane


I don't like the purple of Eve, but the halo it gets at sunrise is magnificent

Both times I did this I was lucky and the final plunge led me in the middle of Eve's main continent, on a hilly area where I can later leave the planet without the full atmosphere to clear. This time there was no big deal with overheating. Ok, there was, those lateral towers are exposed and they can explode, but rotating the ship on its axis prevents the problem. At 10 km it's time to open the parachutes


parabrakes first


ejecting the upper thermal shields (which were being used as parachutes anyway) to make room for the real parachutes. I don't know what's exploding, the shields are still intact


By the way, it's night, but you can clearly see the rocket because i discovered how to enchance light. Makes for much better screenshots


the parachutes open at a high altitude, giving me more time to land the plane


Removing the top tower, leaving room for the last parachute to open


After the speed stabilizes, removing the rear shield. It floats down gently, barely faster than the lander. Gotta wait a bit until it reached some distance, so the plane won't crash into it by accident


The plane is now on its own. It slams against the boosters going down, but slow enough that it doesn't get damaged


the propellers don't work now, the plane must land as a glider. This one is small and manueverable, so it's not hard.


The plane lands, here you see why it could not use the propellers. This bug strucks when you activate them in vacuum. For the other planes i remembered to turn off the rotors and lock them, for this one it was too late.  I tried to fix it with eva construction, but it was too hard to get a good alignment, so I used the alt-f12 menu to get a new plane. Fixing bugs is a legitimate use of the alt-f12 menu.

The weel instead happened on its own, it's the old bug of ship parts getting misaligned. In fact, the second time I did this mission I remembered to lock the rotors before spaceflight, and here is what landed


But at least the propeller blades were attached correctly!

I tried to use it for a bit, then I gave up and used the Alt-f12 menu this time too. On the plus side, i don't think this will be an issue with the Laythe and Kerbin planes, as those don't have such a harsh reentry and multiple parts and struts to mess up with physics. I'm more worried of those planes getting broken before reaching their destinations, but that's part of the mission.

After landing the plane, I have all the time to turn back to the lander and let it glide down gently.


Just like this! Errr... back after the advertising!

A design flaw of the Eve sucks, it's narrow. This is further compounded by me unthinkingly attaching the engines any way they would, and the mammoths aligning their narrow side to the narrow part of the rocket. I did not detect this problem during testing, apparently I picked completely at random one of the few spots flat enough to keep this rocket upright. I had to repeat the landing a few times until i found another suitable one. I corrected this mistake the second time, by turning the mammoths 90 degrees and adding landing struts to the exit pods.

Of course, landing on Eve is already difficult enough, landing an airplane as glider on Eve while a big rocket is falling by parachute is harder, and having to stop and take pictures of the whole process makes it even worse, so I had no intentions of snapping more screenshots. Anyway, I eventually landed on a flat spot.


Now the parachute towers look like outstretched arms screaming yes, i made it!

By the way, you may notice the decoupler remained stuck on top of the command pod. This is also a problem I fixed the second time, but apparently it didn't affect ascent too much


The improved version, with landing struts


The parachute towers are ejected. Do appreciate the sepratrons on top doing their job of pushing away from the rocket


Finally all is stabilized and I'm starting to breathe again, when suddenly a big object drops from the sky over my rocket! It's the airbrakes tower, that fell in a perfectly straight line


Luckily, it was going slow enough that it did not break anything. When I remade the rocket, I made the parachutes slightly asymmetrical, so it would fall somewhere else.

The plane then rejoins with the Eve sucks, so i can get a nice group picture



The landing sequence scattered debris for kilometers. This whole portion of Eve now looks like the aftermath of a rave party



What part of "smile for the camera" is not clear?


And, of course, eva experiments!

5.4) Flying over Eve


Propeller flight on Eve is really easy, and for once I'm not trying to make some crazy hybrid plane-space-ship-subterranean vehicle. Making a simple plane was easy. Of course, as it was easy, I didn't put enough effort into it, so now it doesn't fly straight without SAS. But hey, it's small and it has some good reaction wheels, that compensates.

This plane uses solar power to recharge the batteries, so I waited until dawn before sending Jeb to soar towards the south pole. I picked Jeb for the mission because Bill and Bob always land, while Jeb and Val take turns standing on Bolt. I figured, since he's missing half the landings, he should be the one to get the opportunity. The second time I did this I sent Val instead.


The plane is really manueverable on Eve, it takes off at 30 m/s, and to land I reverse the propellers angle and it practically stops mid-air. I am flying with the front bay open because kerbalism science measurements take time, and I put the science instruments in there. In the second version I swapped them on the back for more stability. Also, since the plane was doing so well, I included a robotic arm and a second, more powerful, deployable antenna, so the plane could keep relaying science after Bolt left the system.

The first version of the plane did 140 m/s with the cargo bay closed, 110 with the cargo bay open. The second version, with the robotic arm to weight it down, did 110 m/s.


putting that robotic arm to good use


cockpit view



I gathered a lot of science data. I got 8000 science from transmitted data, before counting the ground and air samples (in kerbalism, samples only give science when returned, or when put in a lab)

I am of two minds on the Eve landscape. On one hand, I don't like the color and most of it is dull, with a sort of washed out look. But a few places are surprisingly nice, with great cliffs and majestic scenery. In the end it was a nice trip, I'd recomment flying over Eve.

After a few hours of flying, made longer by a few deviations to get more biomes, I reached the south pole. There, I discovered that what looked like a nice point from orbit is actually a fairly large area, and the monolith was nowhere in sight. I had to fly around in circles for a while before finding it hidden in a valley


The black dot in the center of the screen is the monolith seen from the cockpit


Now it can be seen clearly


Good thing I am using light amplification, because valleys near the south pole are permanently shrouded. Here is how the place would look with natural light. Even fairly close and knowing it's there, I'd never spot it.


The marker is the flag I planted on the monolith before taking the picture

At this point I was near the south pole, and poles are generally interesting, so I went to check


turns out the south pole is a cliff over the ocean


I wonder if there is any pole without terrain glitches?


A stone floating midair


And this is the furthest I could go. Beyond this point, the cliff exhist only partially. Any attempt to move on caused Jeb to fall to his death


As you can see, this cliff exhist only when seen from Jeb's left side. From the right side, it disappears


So I named it Schroedinger's cliff. The cliff is 1500 m high, and it's either perfectly vertical, or close enough as to make no difference


Unfortunately, I couldn't write it on the flag. The tiny motion necessary to plant it was already enough to make Jeb lose his precarious footing. I didn't have time for writing


If the cliff exhists on only one side, the obvious experiment is to drive the airplane through it. It explodes in midair


On the base of the cliff, though, it is possible to drive through the glitch


It's like an entrance to the netherworld. I explored it a few minutes before coming out again. Nothing interesting in there, no damned souls or anything

After visiting the south pole, I took another detour to visit a tiny, elusive biome called Olympus. I figured it would be a big mountain, and I wanted to check it for the possibility of landing there in the future. While I was going there, I had to stop for the night on a small island on the explodium sea. The sunset is really magnificent. I can forgive Eve its ugly color and its horrible atmosphere for this



My hydrogen storage for the fuel cell was more than adequate to pass the night. The next morning I recharged for a few hours before taking off and reaching the biome.

Turns out Olympus is two mountain valleys, while the actual bigger mountain on the planet is a bit further off


So I named it Mount Not-Olympus, of course

It was well worth checking this place. Most mountains in this game are just random bits of tall terrain. Even the higher mountains on most planets are nothing special to look at. This is something different. A big pyramid of rock rising 3 km over a high plateau. It's 7540 m, and as far as I know it's the only mountain on Eve to rise above 7000 m at all.


reaching the top following the steep incline challenged the propellers, but the plane was up to the task. In the second version, barely.


And this is the view from the top. The north face goes down straight to the water, a sheer cliff 7.5 km high. To my best knowledge, it is by far the highest cliff in the Kerbol system. I had some fun driving land vehicles down it. So far, I never managed to survive to the bottom.

Finally I returned to the Eve sucks


I think I actually crashed over it to take this picture

Finally, the full route over eve. It must be close to 3000 km. This is on my second attempt; the first time I landed more to the east, on the other side of eastern sea (the long, narrow body of water in the center of Eve) and my trajectory was more streamlined, not touching it or western sea



Olympus is the easternmost point touched here. Mount Not-Olympus is the one slightly to the north-west

Eve scouted for lots of science, it's time to get back.

5.5) Rejoining Bolt


Transfer all the science data to the command pod. GO

Transfer the 300 kg of science samples to the command pod. GO

Detach the elevators. GO

Wait for the proper orbital alignment to match Bolt. GO


Say your last goodbye to Eve. GO




Experimenting with various orders of turning on the engines, because I don't remember anymore the optimal one. Turns out the central skipper is better not ignited until after the mammoths are ejected

This thing was much easier to fly than the FU Eve, and much more efficient. It weights little more than half its predecessor, and it has a much greater payload to orbit, and a greater deltaV. It's still not perfectly stable, but it doesn't require as much steering. And it can detach the boosters at up to 400 m/s, though it's risky to do so at over 300 m/s. I never took a screenshot at that moment, too fast.

I still failed to reach orbit the first times, which is telling of the difficulty of leaving Eve, since i was starting from 2200 m and i tested this thing successfully at sea level.

The optimal ascent, turns out, is to accelerate up to 350-400 m/s before throttling down the mammoths. I run the boosters dry at around 18 km altitude and 400 m/s, at which point the second stage kicks in. If the boosters don't crash into the rocket, which, at this speed, is a bit of a hazard, the second stage has a TWR of about 1 (and it uses both the Skipper and the Cubs). It will actually slow down a bit for the drag before stabilizing and accelerating again. That stage lasts until some 50 km of altitude and 800-1000 m/s, at which point it is ejected and the last stage has 3200 m/s to orbit. I reach orbit with around 500 m/s. Once I managed it with almost 900 m/s. On the first attempt, the one I scrapped because I realized I had then no acceptable way of returning to Bolt (it takes some 1300 m/s to rejoin Bolt from the low orbit).


Right after detaching the first stage



The second time I was starting from a bit lower, 2000 m, and I had more weight in science samples. And I added an OKTO2 to the command pod because it can store a lot of science data (I had to abandon some on Eve the first time) and an extra hydrogen container, but that was less than 100 kg total. I have a hard time seeing how all that could have caused much difference. And yet I tried a dozen times to orbit again, I could never do it with more than 400 m/s. Which makes me skeptical about actually succeeding at it from sea level. And yet the very first time I tested this rocket, it reached orbit from sea level with spare fuel! I wonder what I did right that time that I could never figure out again.

But this time I have Taxi to come rescue the command pod. It is small and efficient enough that those 500 m/s only translate to a few tons of nuclear fuel


Meanwhile, I also sent the GYTH to Gilly to searc its monolith. Finding a Gilly intercept is always an excercice in creativity. Gilly's eccentricity and inclination are such that if you try to do it by the book, matching inclination and then doing a Hohmann, you always end up spending more than if you just fling yourself in the right direction at the right time.


This time I did choose to intersect it directly from my polar orbit


Reaching Gilly a few days later

Finding the monolith on Gilly was actually much harder. The problem is, Gilly has such a tiny SoI (around 100 km) that it is impossible to have a high orbit. The rovemate is the only core that can detect anomalies at 100%, but it has a narrow field of vision, and with the altitude limit, I could not spot the whole planet. I could look at all the equator by orbiting equatorially, and I could see both poles from a polar orbit. But I had no way to consistently control all the middle latitudes, and the monolith turned out to be exactly there. It took me many orbits to find it at 40° N 140° W.

Having done its job, GYTH is returned to Bolt with another highly creative orbital solution


It's curious, I tried a lot of different orbits, and the cost for rendez-vous is always very similar

After a bit of matching orbits, Taxi has reached command pod and docked to it


A bit more of orbital matching, and it reunites with Bolt


Here I must prepare for Gilly landing, which means docking command pod on the rover base (I still haven't found a name for it). The pod also needs new life support supplies. I previously moved the rover base on the front, in preparation. I'll only have to make this swap two or three times


Now a service probe must grab the command pod, since it has no mobility on its own


The pod is detached


And brought to dock with the rover base


Wasn't a bad grabbing cause i was pushing through the center of mass. Still, grabbing the command pod on the front would have made for easier manuevering


And Taxi, still carrying the pod attachment that I now name Heavy lander, rejoins Bolt from the bottom


The new Bolt, much more compact after losing the Eve lander

5.6) Driving on Gilly


Now it's Gilly's turn. I decide to send the rover alone, it has 2000 m/s which are more than adequate to go to and from Gilly. I also use only two sparks, they have higher Isp and by using two I reduce the risk of failure.


"Standard" Gilly transfer


Detaching rover from Bolt



First visual contact with Gilly


Injection burn


Instead of orbiting, I turn my trajectory into a direct approach for the landing site

My clever landing solution did not take into account the low gravity of Gilly. It took over half an hour from the last picture to actually touching the ground, and by then the monolith had moved. Quite substantially, because Gilly rotates fast. My target was 140° W, and I actually ended up 150° E.


Just before landing

I was in doubt on how to proceed. Wheels are useless on Gilly. Suborbital jumps are easier, but pinpointing the monolith is not going to be easy, and I'm not sure how close I need to be. I can send a kerbal with a jetpack, but it's less elegant than bringing the whole rover there.

Well, first thing first, let's try to put this robotic arm to good use. There is a surface feature just near my landing site.

Of course, to align with it, I must use wheels. And so I set to the task.

At first I stumbled. My instincts on how to drive on worlds with higher gravity betrayed me. I had to be careful of SAS, and of reaction wheels not taking orders from the regular commands.

But bit by bit, I eventually figured out how to drive on Gilly. The trick, of course, is to do everything slowly. Activate SAS, give a gentle push to the accelerator, move at 0.5 m/s. By now you're balancing on two wheels, so now deactivate SAS and let your rover go back to the ground. Now activate SAS and accelerate another bit more.  By the time I reached the surface feature, I was confident I could reach the monolith too



Obligatory group picture. This time I left Val on Bolt, after she did drive the plane around Eve


Obligatory eva experiment. I wonder if that golf ball will end up on an escape trajectory...


Gilly from inside the pod

So I set out to drive across Gilly to the monolith. Obviously you can't drive fast on Gilly. 15 m/s is orbital speed. I reached as high as 4 m/s before I started bouncing on the ground. On the plus side, though, Gilly is so small, I don't need to go fast to reach around it. It took less time to drive around Gilly than to fly around Eve, despite the plane being much faster.

And I am glad I took the time to learn to drive on Gilly and spend a couple of hours on it, because it's truly beautiful. One of the best planets out there, despite its small size. Or perhaps because of it.







Finally, the monolith. Most of those pictures were without light amplification


And the route undertaken

Now I must wait on Gilly a couple of weeks before the orbital mechanics are again good for rejoining Bolt. I take the chance to complete seismic experiments for one biome, as they took 15 days (a gravioli reading takes instead 90 days, and some scanner experiments take years. crew reports, sample collecting and other basic activities only take a few minutes, though). During that time I had to weather a couple of solar storms. After discovering that the monolit's shade does not protect from the sun, I take advantage of the low gravity to cover myself



flipping the rover around to protect the crew pod from solar storms

This time rejoining Bolt was more expensive, over 600 m/s. Bolt was in the wrong part of the orbit, and I had to pay to make up for it. The transfer would have been cheaper if I could wait another orbit, but the command pod has life support for one month, and that's less than two Gilly orbits



Rejoining Bolt

I spent some 60 days around Eve, and I am afraid I may have lost a convenient transfer window to Duna.


Edited by king of nowhere
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But the thing is that oxygen and life support on a ship this large won’t take much away much delta v, so you can detox them and control with probe. And with rad shielding, at max, a few percent taking several days to heal is acceptable enough to keep it at zero even with solar storms, especially aided with active shields, which you have 2 of.

Edited by Single stage to ocean
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  • 2 weeks later...
Posted (edited)

Part 6: tumbling on Moho

Bolt splits in two; the habitation module and lander go to Moho, while the main fuel tanks go directly to Duna to save fuel. Moho is explored


6.1) BolTransformer


According to the alexmoon planner, I accounted for up to 10 km/s fuel budget for Moho. Almost half my total, just for this one planet. But I didn't worry much, because I had a few ideas to reduce that price. And the main one is splitting the ship.

But wait, didn't I say that I wanted to orbit every planet? Yes, and I will. The core of the ship is the habitation module, with all the crew and life support and communication and science instruments, and that's going everywhere. But the fuel tanks? Those are not part of the ship; this is not like the DREAM BIG sending a ridiculously overpowered Trucker to Moho while the rest of the ship and most of the crew went away. This time the whole ship goes to Moho, minus a few fuel tanks that are not needed - because ferrying a lot of fuel tanks all the way to Moho only to cart them back is a waste. And sure, those fuel tanks make up, like, 80% of the ship's total mass, because the rocket equation is a harsh mistress. But they are, nonetheless, only fuel tanks.

I calculate that I will need the habitation module, the command pod and rover base, the Taxi, and two stacks of drop tanks. I'll also keep a service probe.


First thing, as usual, is to run a full maintenance before leaving part of the ship without care for years.


Detaching Taxi and the drop tanks


Service probe is not as good as Forklift to handle fuel tanks, but it will do

Then I try to bind the tank to the back of Taxi... and fail. Of course. Bad design. Those 4 engines are too close to each other and they are leaning out on the back. A new tank cannot fit in that space; it should, but apparently there is a slight bit of clipping so that you can't pass a tank between them. or perhaps you could pass a tank, but only with the most perfect fit, which is not a realistic option. Either way, I can't attach stuff to the bottom of Taxi.

First solution I considered, use eva construction to move the engines in front. But those engines are too big to be moved. Ok, time to get creative. If I can't move the engines, I will move the docking port!


Grabbing parts from the other drop tanks...


And putting them at the bottom of Taxi


Now I can stick more fuel tanks on the bottom of Taxi


Like this


Detaching the habitation module


And docking Taxi to it


And the last fuel tank


Bolt is ready to reach Moho without any extra weight

6.2) Planning the next destination


I have to plan: where do I send the fuel tanks next? This is not something I can improvise later, I must rejoin Bolt with its fuel or I'm toast. So I put quite a lot of work into being sure of my trajectory.

Coming up from the inner system to the outer planets, I will have a huge intercept speed. So there are only two destinations that make sense: Duna, that will let me neutralize some of that speed by aerobraking (Bolt doesn't have any frail gigantor panel, so I'm hoping it can take heat much better than the DREAM BIG) and Jool, where I can get captured by gravity assist.

Then I have to decide a time frame, because that will determine how many gravity assist I can try. The mission is planned to last 20 years; the upper limit is food, I have for a bit less than 30 years, but I'd rather keep 20 as target and have the extra food for safety. I've done the inner system, I need the outer planets, and I know some transfer windows. The critical one is the Jool-Eeloo, because it is the only chance there is to go to Eeloo cheaply and in a reasonable time, and there is only one such window every 30 years. It closes at the end of year 10, so I must be at Jool by then. At Jool I will visit the inner moons one at a time very fast, then retreat and wait to heal from radiation damage. But radiation healing is very slow, it will take me one full year to heal the damage from the Laythe landing, maybe more1. So, I want to reach Jool by the end of year 8. There is a launch window from Duna to Jool in the middle of year 5, so 5:300 is the upper limit for going to Duna.

So, I have to go to Jool by the end of year 8, possibly after having started from Duna before 5:300. I will spend 1-2 years around Jool to heal radiation damage after the Laythe mission, and I will leave for Eeloo in year 10. I will reach Eeloo in year 13 or 14. Then the optimal Eeloo-Dres transfer is at year 14, but it lasts 8 years; I don't have 8 years, but with and extra 1000 m/s I can make it in 4, so, year 18. And from Dres I can get back to Kerbin in two years or I can pass at Duna first in one more year, either way ending with 20 years total.

Then I must decide whether to aim for Duna or Jool. Of the two destinations, Jool is more uncertain; I will have a much greater speed for a Moho-Jool than for a Moho-Duna, and there are limits to how much I can get out of a gravity assist; it may be inadequate. While at Duna I will have, for sure, 600 m/s coming from Eve, and 2 km/s coming from Moho. Furthermore, the only advantage I have in delaying is more time for gravity assists, but I'm still needing more years to reach Jool from the inner system, so I don't have much to gain. Duna seems the safest destination. And from Duna to Jool it is relatively cheap.

Having decided that I will rejoin Bolt with its fuel tanks at Duna before 5:300, I start looking for trajectories. Hohmann transfers are all well and good, but starting on an elliptic orbit changes things. And I am quite happy about it, it makes things interesting

1 And incidentally

On 4/13/2021 at 12:35 PM, Single stage to ocean said:

But the thing is that oxygen and life support on a ship this large won’t take much away much delta v, so you can detox them and control with probe. And with rad shielding, at max, a few percent taking several days to heal is acceptable enough to keep it at zero even with solar storms, especially aided with active shields, which you have 2 of.

this is why counting too much on detox is not going to work. A solar storm would gain me 3-5% radiation, and it would take 10-30 days to heal it. As I get much more than a solar storm every 10-30 days, my kerbonauts would die if I left them exposed, even with healing running continuously. And frankly, I don't understand why you want so much to let the kerbonauts take radiations when you can simply rotate the ship around.

6.3) Eve to Moho


I will keep the trajectory of the engine pack for the next update, where I will bring everything to Duna. Here I focus on Bolt reaching Moho.

The trajectory is a bit underwhelming.


I wait 100 days until Eve is in the right position. Then I make a pure prograde burn to push my solar periapsis to touch Moho's orbit (purple line). I miss Moho completely, but a small burn times me for an intercept on the next orbit.

Yes, complete lack of imagination. I could have gone for an Eve-Eve gravity assist and developed from there. What I made is practically an Hohmann transfer.

There were, of course, many advantages. The thing is, I was quite lucky that when Eve is in the right position for me to burn prograde and exit behind Eve, I touch Moho's orbit very close to the ascending node.  240 m/s get me directly touching Moho, no need for plane changes or other fancy stuff. And while the timing to meet Moho is bad, I can get an intercept in reasonable time for only 160 m/s. 400 m/s total to get there, I doubt I can get any better.

Once at Moho's intercept, I still have 3000 m/s of intercept. But those cannot be avoided, sorry. Those are the minimum intercept speed for coming from Eve's orbit, and once I drop below Eve there are no more planets to use for gravity assists. It should be possible to use Moho itself, but it doesn't provide much kick on a passage. I'm sure @camacju would be able to slow down entirely with 50 gravity assists and course corrections of less than 1 m/s, but I don't have the time to make 50 gravity assists. I must finish with Moho and reach Duna before 5:300. So, those 3000 m/s of intercept cannot be avoided. The rest of my trajectory is very cheap.

And it brings me to Moho before year 4, leaving almost 2 years to reach Duna. I have a much better chance of saving fuel with gravity assists on my way there.


First sighting of Moho


The capture burn will take over 30 minutes. And I must time it well to avoid wasting more fuel. In the end, I had to repeat it three times to find the right moment to start


Dropping tanks


Here I got the first critical malfunction to an engine, fortunately it's one I'm about to drop


who cares about that engine anyway?



6.4) Exploring Moho


I did not see the monolith on my way in, but finding them is very easy once I put a GYTH in polar orbit


The anomaly at the north pole is the mohole. The one on the left at the edge of the planet is the monolith

On Eve I got screwed by my measurement being taken from afar, it was very inaccurate and I had to fly in circles for a while before finding the monolith. This time I won't have the luxury of a fast plane, so I manuever to make a close pass right on top of the monolith. Moho's super slow rotation makes things easier.


It's time to deploy the rover.



And by the way, I found a name for the rover base; it's Stool!


Deorbit burn, once more with a decent twr



obligatory scanning of surface features


Obligatory group picture


roving on Moho

I've been wanting to drive a rover on Moho for a long time. No, I couldn't just alf-f12 there. I did it, but it never lasted; I need an objective to reach, or I get bored in minutes. This was my chance. And now that I finally reached Moho, I have some advice for the rest of you.

Get away from here. Do it now!

Really, Moho sucks. Moho is ugly. Moho is bad and it should feel bad. If Moho and Dres made a contest for the most useless planet, Moho would win - although that's only because Dres is so useless that it can't even win contests, so perhaps we should call it a tie.

The surface is all rough and bumpy and the rover keeps skidding. The surface is also all similar, without anything interesting. It doesn't even have boulders or anything! (yes, ground scatter is activated, every other planet has nice stuff on it). And brown is dull. There are some hilly areas that may be more interesting, but they are on the other side of the planet.

On the plus side, Moho has a nice gravity for rovers and plenty of sunlight, so it's still a better driving experience than Dres.

As a rover, Stool performs better than I was thinking. At first I was going relatively slow (at least compared to what I would do with Dancing Porcupine, taking advantage of its indestructibility), but I have a big advantage that Dancing Porcupine lacks: strong reaction wheels. In the face of a really bumpy ride, setting the SAS to hold prograde worked wonders. I had electricity shortages, two RTG are not enough for the wheels; but I don't want to make this any more heavy, and the energy was adequate, provided I would accelerate downhill and conserve speed for going uphill.


Moho speed record of 52 m/s. I didn't want to go so fast, but once I picked up speed, I started to bounce so that the wheels would not touch the ground. And then  braking would only make me skid. So the only thing to do was hanging tight and hoping to find an upward slope to slow down


The monolith can be seen in the distance


The monolith seen (not very well) from the pod


I landed on the night side and I did drive all the time with light amplification. When I reached dawn, I turned it off to see the real colors. It's still dull, but less so


Meanwhile, GYTH 1 rejoins with Bolt


The path taken. Landing to monolith is 170 km, monolith to goodbye Moho is 240, so a bit over 400 km of driving. Four biomes touched. I could have reached poles by going north a few more kilometers, but I didn't like Moho enough

After coming back to the equator, I can leave this planet. Only problem I have, I don't have enough fuel to return to Bolt, so I need Taxi to come get me. This was just as planned. Unfortunately, orbital alignments meant that by the time of the rendez-vous, Taxi had no communication.

I tried some tricks, including transfering one pilot to Bolt to try and control Taxi remotely, but it didn't work. I could have planned it better, but I felt safe in all the fuel I saved by splitting the ship, and so I was lazy and just slowed all of Bolt on a circular orbit.


Docking Bolt with Stool

This was pretty straightforward. I don't expect any significant difficulty until i reach Jool

Edited by king of nowhere
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But that takes away 1/3 of damage, which could be eradicated with 200 tons of active sheilds, very heavy but doable on an ion ship like I'm doing. Needs 200 ec/s, so you need big solar panels, like Dream Big's. At least Eeloo isn't hellish in terms of radiations belts, and at Jool its pointless b/c it will barely have an effect with the overwhelming radiation.


I apologize for the self promotion but mine can run an ion engine on full thrust in the dark with a little help from fuel cells(just 1/4 of power is fuel cell generated and I can run electrolysis when the engines are off). Just has a TWR of 0.009, but I have nothing to do and can work on other stuff while it burns. Sadly wont work with 4x physics warp, and is unstable. And it lightens as fuel burns off, so at kerbin return I'll have expected 0.013 twr. Still pathetic, but I have ludicrous DV.

I lauched my hab module trying to dock it to the 300 ton engine module before realising it would be easier to lauch the hab module and engine module(the heaviest items) together, so I'll scrap that idea. Luckily, I have a superior service probe, it has high partcount though(32 engines are not going to play nice). They are all twitches and it is 128 tons(two rockomax-64s). After all, I need enough fuel to boost the finished ship to a high orbit. It would be better though to just launch it to the high orbit rather than launch a heavy service probe, so I'll start over and do that. Wasted a day designing and playing. At least it can be recovered on kerbin with a vertical landing, or used as laythe lander(replacing 2 now redundant 64s with just one 32). I can use it for a lot, eg. recovering Eve lander.



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  • 2 weeks later...
Posted (edited)

Part 7: the Duna system

The two parts of Bolt rejoin at the Duna system, and explore it. There are way more malfunctions than anticipated, but the ship is still in good healt. The timing for the Jool transfer is a bit off and will force some extra fuel cost, but a lot has been saved with the previous manuevers, so it shouldn't be a huge problem


7.1) Engine pack goes to Duna


An Eve-to-Duna transfer would require over 2200 m/s of ejection deltaV. Some of that is saved by being on an elliptic orbit, then again, the ellipse is pointed in the wrong direction. But I do have some time to look for gravity assist. I have two options: Eve-Kerbin-Duna, or Eve-Eve-Duna. Kerbin is in the wrong position, and Eve is cheaper to reach and gives better slingshots anyway.

Unfortunately, Duna is in the wrong place and requires an expensive manuever afterwards. But hey, you gotta work with what you have. This is the best I could find:



It starts with manuever 1, 29 days in the future, in Eve's orbit. 300 m/s to exit Eve on orbit a, which is syncronous with Eve's orbit and will bring me back to meet Eve again one orbit later, after a small course correction (manuever 2). This gravity assist will kick the solar apoapsis almost as high as Duna, since I don't have the time to make another Eve flyby I must give it a little help, with manuever 3, an extra 60 m/s prograde to burn at Eve's apoapsis. This gravity assist + burn will kick me on trajectory b, going to the outer system. Here I must stop for a plane change, because the ascending/descending nodes are halfway between Duna and Eve and there's really no way to avoid them. So manuever 4 is the plane fix; though I may end up making it later, it could be cheaper. I learned to not try to plan those long term trajectories too exactly, as they will never come out just as planned; as long as I know they are there, i can always make some corrections. So, this will get my solar apoapsis touching Duna's orbit. Unfortunately, Duna is in the completely wrong place, but time constraints force to meet it at the next orbit. So, to fix the timing, I must make a long, 900 m/s burn in solar space, to raise periapsis and intercept Duna. On the plus side, this will result in a very low intercept speed, so I can probably get away with aerobraking.

In total it's roughly 1600 m/s to enter Duna's orbit at 5:270. Pretty good. I could make it with less than 1000 m/s if I could afford to wait a few more years, but no point crying over what cannot be


Engine pack starts its voyage, still discarding spent tanks like a trail of breadcrumbs


low thrust forces more correction manuevers


The first Eve flyby, with the extra kick manuever. The Eve plane is still there, abandoned behind but still gathering science data (it takes 90 days for a full gravioli scan of a biome, and more to relay the data)


and the subsequent trajectory after the Eve flyby. You can also see the habitation module still en route to Moho


Here is the plane change. I considered waiting, as it should be a bit cheaper after I raise the solar periapsis. But it's a very tiny difference, and making it now makes the planning much easier.

You can also see I have a couple of malfunctioning reaction wheels by now, even though it's been less than one year since the last maintenance


And here is the trajectory after the plane change, before the last planned manuever. The 200 m/s is the intercept, which will be provided by aerobraking

Still 2900 tons of fuel, they will be reduced somewhat after the last manuever, but I can still look forward to reach Duna with well over 2000 tons. My original plan, albeit conservative, included spending half my total deltaV just to get to Moho and back.

On the down side, something went wrong with some of the manuevers, the argument of periapsis is different than its planned value, and I will meet Duna in 5:310 instead of 5:270. Which will force some additional cost to reach Jool, hopefully not too much.


The big prograde burn

Finally it is time for the 900 m/s burn. And here I start to really feel the difficulty level, because stuff keeps breaking up much worse than the previous time. You can see a third reaction wheel malfunctioned, but also an engine broke up. Less visible, a second engine went out, on the bottom right of the ship; this one does not have a red outline because, instead of just malfunctioning, it exploded completely. Which is good, it's less weight I have to carry around. The two broken engines were both on the same side, so I had to shut down an engine on the top to keep the ship stable

It's been only one year since last maintenance, and I already have several critical malfunctions. With the Dream Big I only run maintenance every two years for most of the mission, and none of the components I checked regularly ever broke. None of the engines ever broke for good, either, though that was lucky. And after I finally reunited the ships, and I could run a full check up of the engine pack... most of the systems were reported to be still new! Meaning I cannot repair them. At normal level hardware was new, then it got aging, and then after a while it broke, and if you found it while aging you could service it and bring back to new. Here it seems hardware goes from new to broken without passing through aging.

Still, even though the rate of stuff breaking up is much greater than it was with the Dream Big, I am confident the ship can make it. And it only has 4 crew members that get stressed and break stuff up.


70 days to Duna encounter. Also visible Bolt with its own encounter a bit earlier.


Finally reached Duna! A few more pieces got broken up in the meanwhile. The Kerbin plane, on the right, is almost nonfunctional, hopefully it will hold strong


another angle to appreciate all the stuff that broke up


Aerobraking. I had to lose 250 m/s, turns out the ship can take more. As I mentioned, it was the gigantors that made the Dream Big fragile.


Finally, the engine module is in orbit around Duna, ready to rejoin Bolt

7.2) All roads lead to an Eve flyby (Bolt goes to Duna)


Meanwhile, Bolt - the part of Bolt containing all the essential systems that I sent to Moho - had done its task, and got ready to leave for Duna. According to alexmoon planner it should take 5300 m/s, minus whatever I can aerobrake. This time saving fuel is less important, because this part of Bolt if much lighter and won't consume much, but I'm still looking for gravity assists. No point in wasting fuel.

The cheapest trajectory would be Moho-Eve-Kerbin-Duna, except that would require a very special planetary alignment. I can forget about it. Actually, getting more Moho flybys to raise apoapsis gradually would be even cheaper, but it would take too long, Moho doesn't give enough kick for the manuever to work. So the choice is between going to Eve or Kerbin. I tried both, but it was immediately clear Kerbin was not a good target; coming at it from Moho I had a high intercept speed, resulting in the gravity assist being mostly ineffective. Also, Kerbin's slower orbit makes double flybys too slow, and reaching Kerbin is more expensive than reaching Eve. Eve is the better choice.

Yep. I hate Eve because I have to include a huge special lander just for it, but it actually has a lot of good things about it. This mission made me appreciate the planet a lot better. My next lander will not have a disparaging name.

Anyway, finding a Moho-Eve-Duna trajectory proved impossible, because I entered Eve's SoI from the wrong side. This one was a very hard manuever to plan, but I managed to find a Moho-Eve-Eve-Duna path that would fit in the time limit


The trip starts, obviously, around Moho, with manuever 1: 1100 m/s to reach Eve. Those cannot be avoided, I'm afraid. To counteract the low thrust, I start with an apoapsis raising first. This manuever sends me to an Eve intercept, on orbit a. It includes a small course correction (2). At Eve, things get complicated, because the game does not visualize those flybys well. So here is a more detailed screen


So, during the first Eve flyby, I must make a retrograde burn for 400 m/s (3). As you can see in the picture, to reach Duna I have to raise my solar apoapsis, to do that I have to exit Eve in the direction shown by the arrow, and my first flyby has no chance of accomplishing that. But that retrograde burn lets the planet turn around my trajectory more, and it puts me on course (orbit b) for a second Eve flyby on the next orbit. and this time Bolt will be coming at the planet from the right direction. This second flyby, along with a little help of less than 100 m/s (4), pushes Bolt on an intercept trajectory for Duna (orbit c); Duna is lagging behind just a bit, a small enough difference that it can be handled by a higher solar apoapsis without too much extra cost. The final manuever, 5, is plane change. Not only this trajectory saves something of the 2200 m/s necessary to get a Duna intercept, but raising solar periapsis also reduces intercept speed, to 1300 m/s - still high, but nowhere near as bad as a direct intercept from Moho would be.

Also, along the way I found ways to increase efficiency. At first I was trying to fix the orbital planes, but later I realized that i could use those gravity assist more productively to tamper with apoapsis/periapsis, and come at Duna with a high inclination - the node was very close to the intercept, so it was cheaper to push it on the intercept rather than to reduce it to zero.


Leaving Moho. The bug with part alignment is really wreaking havoc with my poor ship. At least I have good reaction wheels to compensate the shifted baricenter


Eve becomes visible by the naked eye (on the bottom, just above the speed display)


first Eve flyby. I already managed to shave off a bit of cost from this one

And by the way, as I was passing near Eve, I was again able to fly the Eve plane remotely. I took the chance to move it around to a different biome, so it could make some long term science experiments there too. After Bolt leaves the system, the plane has a high gain antenna to relay data to the KSC, but the antenna would break up with wind forces if I tried to fly with it deployed. Those are the last chances to move it.

Yes, it's completely unnecessary for the mission, but going a bit out of my way to perform the extra experiment makes me feel more like this is a real science mission.


Here one engine of Taxi exploded (bottom left on the image). This one actually hurts. On the other hand, I did include extras specifically for this reason. And it graciously exploded, for weight saving

Side note here: I was hoping I could swap out engines as needed with eva construction, discarding broken ones, eventually replacing them with those from spent tanks so I could keep the core engine module and Taxi always functional. That's not the case, as it turns out the bigger engines cannot be manipulated by eva construction, under any condition.

In the future I will plan for that, I will attach engines to docking ports so I can move them around with something like the service probe. The extra mass for the docking port is more than compensated by being able to discard dead mass in the form of broken engines. I'm more worried about the impact of the extra parts on my cpu performance.


Bolt leaves Eve on the right course for the second flyby. This one will already achieve a solar apoapsis over 21 Gm without any need for further corrections


A small course correction to refine the second flyby, and a 110 m/s plane change (could reduce them to 80 later) set the final course for a Duna flyby at 5:270


Finally arrived on Duna. Slowing down to a manageable aerobraking speed. Also, despite constant maintenance, Bolt also lost some pieces.


Aerobraking. The main limitation was the rover wheels


I moved a kerbonaut in a cupola just to snap this picture


As a result of not matching the orbital plane, I entered Duna with an inclined orbit. A couple of really cheap manuevers while far from the planet took care of that.


Going to Ike. Ike is the best parking spot around Duna, as it is cheaper to leave Duna from Ike.

Unfortunately i don't have any chemical fuel left to operate the lander, so I must wait for the engine pack to come along. It sucks, because after 5:300 the transfer window to Jool closes pretty fast, and the extra cost quickly increases by hundreds of m/s. Worse, the cheaper trajectories are the slower ones, and I still need to get there in year 9; I have to pick even more expensive trajectories.

I really don't like having to wait while I'm missing the transfer window, then having to wait more while Stool lands and finds the monoliths. This was so bad, I actually considered leaving Duna system in a hurry without landing as soon as the engine pack arrived, and coming back to it after Dres.

A quick check at the transfer windows between Dres, Duna and Kerbin around year 18 dissuaded me from this course. The deltaV cost for Dres-Duna-Kerbin is no greater than a direct Dres-Kerbin, thanks to aerobraking at Duna getting rid of inclination issues. But the planets are in bad alignment, forcing a long wait for transfer windows. I still want to target 20 years.

I even considered skipping Jool, going for Eeloo first, and then to Jool. The transfer window is actually nice, and Eeloo-Jool is only 300 m/s at the right time. Unfortunately, Duna-Eeloo is over 2000, so, much more expensive than going directly for Jool.

So in the end I'll just go forward with the plan. I will spend at least 500 m/s extra for going to Jool, which sucks. But then, this little stunt with splitting up the ship, and then all the gravity assists, saved me a lot of fuel. Much more than I'll have to spend now. Also, the original plan called for 5000 m/s to explore Jool. Back then, I still had not planned for Taxi, which I added later. I spent much less fuel than I planned, so I can afford to waste a bit extra for Jool.

Meanwhile, I can save some time by preemptively scouting for the monoliths


Detaching Get Your Tinfoil Hat

7.3) Boltransformer 2


Now I am safely in Duna orbit, I located both monoliths, and I have to wait the engine module before i can land. And every day I wait is going to increase the cost of going to Jool. Better to do everything I can while I am here to speed up operations. To save time I reassemble Bolt again in preparation for the next part of the mission; having Taxi and Stool ready to be detached and sent to Duna. Also, it's better to do the manuevers without the engine pack because I have less parts in physics range to slow down the game. It's currently running smoothly.


Dear service probe, what would I do without you?


Step 1: hitch the service probe to the remaining drop tank


Step 2: split all the pieces - Stool, Hab, Taxi, Tank. By the way, look at how the fuel tanks alignment is getting worse and worse


Step 3: dock Taxi with Stool


Step 4: dock Hab with the tank. Also the parts of Hab are getting badly misaligned


Upon docking, the two parts exploded. I assume because of all the tension of the warped parts. So, step 5: reload. Knowing this can happen, I always save the game shortly any docking manuever


And hey, upon reloading, all the alignment problems got fixed!

By the way, @Klapaucius, this part may also address your question

7.4) Hiking on Duna


Engine module is finally coming, and with it my refueling. As it is already past the transfer window, every day I wait I am losing fuel. So, instead of waiting for it around Ike, I send Taxi+Stool on a fast intercept trajectory. Taxi has much lower consumption than the full Bolt, better to make some expensive manuevers with it than with the whole ship.


I would have liked to meet the engine module at apoapsis, but orbital mechanics prevent that. I have a relatively cheap trajectory to meet it later (the trajectory is cheap, but the encounter speed will be high, because the ships are in different orbits), but it will only be 1 hour before reentering atmosphere, I will have to be fast.

By the way, Taxi lost an engine and has an asymmetrical engine. Of course using it would unbalance the ship; but I discovered even leaving it shut down unbalances the ship, because that engine is still extra mass that's not balanced on the other side. So I put the thrust limiter at 10% on it, and the ship flies fine.

I'm sure I could operate it with one engine at low thrust if I really needed to, but I hope I won't.


Close encounter set. Meanwhile, engine module is on its way to catch Ike on the next orbit without any further correction




Despite Duna looming closer, I still take the time to fix the engines. Less likely I will break some more on the way to Ike


Refueled, Taxi and Stool set for an aerobraking trajectory


I experimentally try to split them in the atmosphere to make two aerobraking in one. Stool, less aerodinamic, will stop on the planet, while Taxi will have enough energy to stay in orbit

Actually, even Stool needed an additional atmospheric passage. I could have set a lower periapsis


the double aerobrake works. As long as both ships stay in physical range, both are braking and none gets deleted


I'm landing just on the side of the canyon.

By coincidence, it's very close to where I first landed a Digger in the previous mission. And incidentally, I still have 50 m/s to rocket brake, despite the 300 kg parachute. That's very puzzling; the Diggers weighted over 80 tons, they had 800 kg of parachutes (1% of the mass), and they fell at 30 m/s. Stool is 15 tons, it has 300 kg of parachute (2% of the mass), and yet it falls much faster. I'll have to figure out why, it will be important for future atmospheric landers.


All landed safely!

Actually, the landing wasn't flawless. When I make low thrust manuevers, I generally turn on only a couple of engines, to reduce the overall chance of malfunction. Turns out, I forgot to reset the settings since last time I did such a manuever. So I activated the rockets, and only a couple of them started. I could have recovered by pressing 5, which turns them all on, but I wasn't ready for it. A few seconds later I slammed into the ground at 30 m/s. The sturdy wheels took the impact, though a couple of them broke.

I decided to keep the save as it is, because I also forgot to save since before atmospheric reentry. But I'm running out of repair kits (Moho was a real wheel-killer), I will have to be more careful in the future.


So, this is my landing position, with the various anomalies marked. I didn't try to aim for a landing close to the monolith because I am using this mission partially as an excuse to drive. I like driving rovers, if I have an objective. As the monolith is in the souther ice cap, it will be quite the trip. I will also get a chance to visit the mast cam along the way.

Duna has a comfortable gravity, perhaps a bit too much because going uphill was difficult. To climb mountains, I had to frequently stop to recharge, and I couldn't accelerate on slopes past 10 degrees (I wonder why wheels are so weak? This is still a low gravity world). The terrain is varied without being uncomfortable, there are high mountains and deep canyons and rolling plains. The atmospheric drag is virtually unnoticeable until you go past 50 m/s, and at that point you're likely dead anyway.

Overall I had fun driving on Duna, enough that I often took detours to visit additional biomes (I got 9). I spent 3 real life days driving - and also 3 kerbal days. No, it does not mean I played 6 hours each day, I had to pause to recharge the batteries.

Most of Duna is not much to look at, but there are highlights


I'm taking one of those scanning pictures on every planet.

By the way, speaking of surface features, beware blueberries. They are small and hard to notice, and they will break your wheels!


I miss the IVA panoramic view of Dancing Porcupine (I actually considered putting a cupola, but it would have required a complete redesign). Still, here I got Ike through the window



Going down the canyon at full speed enables some really cool jumps. And also some cool explosions. Eventually I had to give up and go down slowly


I don't like Duna's sky color. The night sky is much better.


the mast cam sticking out of the ground




I don't like Duna's sky in daylight, but it is beautiful in twilight. It's blue like... like Kerbin's sky. In retrospect, if I wanted to see a blu sky, I should have stayed home




I also appreciated the gradual shift between regular land and ice cap, so that the boundary is visible at a distance, but up close I can't tell where it starts

Meanwhile, engine module rejoins with the rest of Bolt. At Jool I will want to release the Tylo descent stage and the disposable rovers, so I assemble it in a way that would make it easier to disassemble later


The small thing in the middle is the atmospheric ascent stage, used on Eve, which will be used on Laythe and Tylo



Bolt reassembled. Except it doesn't look much like a bolt anymore. I wonder if I should change its name again...


Back to Duna, finally I reached the monolith. It's twilight again because I've been running eastward


Going northward

My original plan was going to the equator before orbiting again, to have no inclination. But I suddenly decided to cut short my drive to minimize the time spent at Duna (remember, I am losing fuel eveyr day I delay going for Jool). I need the right position of Ike to launch, and it happens every 3 days. By some handwaved calculation (and gross overestimation of how long I'd need to visit Ike) I decided to leave in a hurry. Probably I was also getting fed up with Duna. After all, I traveled an estimated 700-800 km over it.


The path taken over the planet


Leaving Duna. Stool's aerodinamics is awful, I spent 1400 m/s even launching from 5000 meters of altitude


Rendez-vous. I spend a few extra to force an immediate encounter with Taxi. By now the ship is so light, it manuevers very cheaply


And a creative trajectory to intercept Ike, and Bolt, at the first occasion. It's actually rather cheap, because I left Bolt parked on a high orbit where it's easy to make plane changes


Finally, Taxi+Stool rejoins with Bolt. But only long enough to quickly get new fuel (only half tanks, Ike doesn't need much deltaV) and to refill the nitrogen tank (I lose some at every EVA, and I didn't think to add a nitrogen tank to the command pod. If I run out of nitrogen nothing too bad happens, I lose pressurization and the kerbonauts have to stay inside the suits, gaining more stress, but the effect is small over a few days. Still, I prefer to get a refill.

And then, onward to Ike. Or, more appropriately, downward.

7.5) Racing across Ike



Landing on Ike is easy, no need of detailed explanations.

Once on the surface, I started driving. I wasn't expecting much; My only previous experience driving on Ike was with the lander/rover of the Marco Polonium, and that was an absolutely crappy craft made to be lightweight and cheap. It was barely capable of moving to the nearest surface feature to take a scan before leaving again. Still, I did drive the Dancing Porcupine across Mun, and while I liked it a lot, I also skidded a lot and crashed a lot. Which is all right, Dancing Porcupine is armored, crashing it around is part of the fun. Stool is not armored.

Turned out, Stool's reaction wheel is even better than any armor. I didn't even want to put it there at first, it was just a convenient part to provide thickness between the two docking ports, to attach the other parts. And ok, a redundant reaction wheel is always good, those are pretty fragile and in my past experience they are the first pieces that break (I already have the command pod wheel and a small backup wheel in the cargo bay). But if I could have skipped that large wheel in favor of a lighter part, I would have.

It was a fortunate accident of engineering. On Moho and Duna the reaction wheel was barely adequate to keep Stool upright. But on this low gravity world, it shines.

Bumps along the road are inconsequential. Skidding is inconsequential. I can drive as recklessly as I want, my reaction wheel will keep me pointing prograde. Even when I go flipping, I stop and reassert control well before I touch the ground again. Factor in that the gravity is low enough that going uphill is not a problem - Ike is FUN

On this little planet, I cruised at speeds averaging 50 m/s, going as high as 70 m/s, with only a single unfortunate accident. 

I can definitely recommend driving on this planet. Bring extra reaction wheels.


A cool jump


Another cool jump

P.S. I have the reaction wheel selected because I need to toggle it on/off frequently. When I accelerate i want no input from the reaction wheels, as they are powerful enough to flip my rover. But when I drive I want it turned on, to keep prograde.  And when I suddenly start spinning, I must know immediately if my reaction wheels are turned on or off.

P.P.S. You may wonder why I don't set the reaction wheels to SAS only. Very simple, SAS keeps you prograde but does nothing for roll. A correct front/rear orientation is no good if your wheels are pointing towards the sky.

P.P.P.S. If you're wondering how I can keep prograde on this rover that's build vertically, there's an okto2 probe core underneath one of the trusses connecting the central body to the fuel tanks. I put it there for this specific reason, one of the small improvements I did after the first failed run.

P.P.P.P.S. No, I actually put the core there just because I didn't want to have to grab the Stool base with a service probe every time I wanted to move it. That it was also useful for pointing prograde was merely serendipitous. This rover is the most accidentally successful vehicle I ever built!



:DLots of cool jumps!:D


A cool panorama. With its high mountains, Ike has dramatic scenery. I loved it. Everyone, go land a rover on Ike already!


Those little boulders have been my major killers in this drive. The first one, I thought I could pass over it, but it collided with my docking port. The second one, I landed on it after a jump


This monolith is flying, so I parked underneath

The monolith was 60° N. I landed on the equator, because I wanted to drive around - and I'm very happy I did. It also took little time, maybe 1 hour, beccause Ike is small and I could go fast. I raced maybe 150 km, including some detours to visit an extra biome. In all this time I had a single accident, the aforementioned collision with the surface feature, but it happened shortly after I saved. I generally stop to save every 20 km, but this time I felt so safe, I went as far as 80 km without stopping - also because, when you're pushing past 50 m/s and going downhill, you're not much driving as bouncing on the surface in a sequence of suborbital jumps, and braking is kinda hard.

I reached the monolith and I could have come back, but I wanted MOAR IKE! I decided, instead of coming back to the equator, to take the long way and pass over the north pole, and reach the equator on the other side. And then who knows, perhaps even pull an Elcano?

So I started north, racing again


moar cool jumps


look how high and how fast I am jumping this time!

.... this is very high and very fast. Am I sure the wheels can take this impact?


yeah, pretty much

Yep, I pushed this rover a bit too much, in the end the wheels couldn't take it anymore. I was at 75° N when this happened, en route to the pole. No harm done. I reloaded from the previous save, the monolith.

And here's what happened


Puzzled, I tried again. And again. And again.


Yes, the game is kindly giving me warning that breaking open my command pod has depleted my nitrogen reserves. Thanks, kerbalism. It may be as high as fifteenth place in my list of direst problems right now

Turns out, Landing underneath the monolith was a mistake, because the game was glitching me inside the monolith upon reloading.

At this point I had to go to the previous save. Which was over 50 km before.

Well, I actually cheated my way back to the monolith with alt-f12. I already reached there fairly, not my fault the save got glitched. Anyway, this accident dispelled the magic of Ike. I lost interest for making extended tours, I just wanted to get back to the equator and move on.

Of course, I still had 150 more km to return to the equator. I could keep up with cool jumps some more


On the way south, I passed over some of the highest mountains on the planet, reaching as high as 11 km altitude. An 8 km climb between my highest and lowest points.

At some point, checking the map, I saw this


Taxi is reaching periapsis in 30 minutes. Can I catch it there before it passes? Can I race Stool against an orbiting vehicle? Sounds fun, let's try.

Being 30° N, I need to cover 1° per minute. More, to reduce the gap. At first I had to go uphill, and I couldn't gain on Taxi. Then I passed a crest, and it was downward all the way to the southern emisphere.


70 m/s, and this time I survived


Pushing Stool more and more recklessly, I gain some time


Exactly 1° per minute to make it


I'm making it! I'm doing more than 1° per minute! I think I should I start thinking about breaking too, if I don't want to end up all the way to the south pole


This jump is very high and very fast! It's very similar to the one that killed me earlier :0.0::0.0: Will I survive? Will I have to reload the last 30 minutes?


The rover is safe, but the front right wheel broke. A broken wheel also fixed my need for slowing down, though it is a half miracle i didn't break anything else in the process

But I am still 3 degrees from the equator. I have time, but I must race the last distance


Bill will attempt some high adrenaline engineering there


Done! Fixed a wheel of a racing rover, while wearing a space suit and hanging for your life from a ladder! Bill, you are an engineer with balls of steel!


Victory! I reached the equator 30 km ahead of Taxi, which translates to about 1 minute. Just the time to plant one last flag before the rendez-vous.

I thoroughly enjoyed racing over this little world. I wonder if I would have still enjoyed it had my rover broken in that last jump, though.


The path taken, slightly over 300 km. I was much faster than at Duna, with less time spent reloading accidents, and did all this in a saturday afternoon. Only 3 biomes, though.

With this, it was time to move on. I spent enough time around Duna. Now I will finally see if my calculationshandwaving about radiations at Laythe are correct. I will finally see if my landers perform well, it at all. The truly dangerous part of this mission begins as soon as I reach the gas giant.

Bolt has still almost 2000 tons of fuel left. I expect at least feeding the NERVs won't be a problem

Edited by king of nowhere
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Posted (edited)
On 4/4/2021 at 1:19 AM, king of nowhere said:


A thin, long, narrow ship like this requires a lot of autostrutting to avoid wobbling. And autostrutting does not mesh well with kerbalism, resulting in misshapen ships. But I learned by now that those bugs will be reverted between saves and are not fatal, so I'm mostly ignoring them


This is an amazing undertaking. I just came over after seeing it posted on Thread of the Month.  I'm learning a lot reading about your process and design decisions.

Question: in the case above, is there a reason not to use rigid attachment?  I never use it on planes or landers because it makes things too brittle, but I do use it from time to time on rockets and orbiters.  

Edited by Klapaucius
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16 minutes ago, Klapaucius said:

This is an amazing undertaking. I just came over after seeing it posted on Thread of the Month.  I'm learning a lot reading about your process and design decisions.

Question: in the case above, is there a reason not to use rigid attachment?  I never use it on planes or landers because it makes things too brittle, but I do use it from time to time on rockets and orbiters.  

i tried using rigid attachment in the past, and as you said, the ship was brittle and broke easily. i didn't even try in this case.

it may even be that it could work better. but it would be very hard to gauge. i tried rigid attachment with my previous ship Dream Big, which also had problems of structural stability, and I didn't notice any visible improvement. The problems only happen occasionally, so to compare the better way to handle them, I'd have to try both versions with and without rigid attachments, for prolonged times, and run detailed statistics. A lot of boring work. On the other hand, autostruts alone reduce stability problems to a manageable level; parts spontaneously detaching, after the initial assembly phase (where i always forget to autostrut some key component), are extremely rare. parts getting misaligned are ugly, but they revert spontaneously and they cause no lasting harm.

Overall, improving the stability would require too much work for too little gain

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