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Lucy in the sky with deadly radiations: An attempt to make a grand tour using kerbalism


king of nowhere

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Ever since I learned about the kerbalism mod, I knew I wanted to try my hand at it after I’d be good enough at the stock game. And I wanted to create a big, self-sustaining spaceship.

Always in the stock game I would have liked to make things elaborate, but had no reason for it. An external crew pod seat and an engine is already enough for a grand tour. I give my kerbals more luxurious accomodations, but aside from that, why bother? Kerbalism gives me exactly the excuse to do what I was looking for: make something big and majestic. And not just by adding parts that look good, but in a way that would have a purpose.

First I experimented a bit with a career, but I soon got bored. Making routine missions in all safety is just not for me. Making a Mun landing with just a food canister and a couple oxygen tanks is not really different or more entertaining that playing the stock game. I need challenges. So I skipped directly to the prize.

The mission purpose is to build a majestic spaceship called DREAM BIG and perform a grand tour with the kerbalism rules. There is one exception: I will use the stock ISRU functionality, but I will only refuel at Duna. I will liberally use save scumming to protect myself from failed manuevers (as I keep saying, I have no patience for making everything just so), but I will never use it to revert a malfunction. Or, if I do, I will admit the defeat.

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A spacewalk around the final version of the ship

 

On 12/17/2020 at 5:25 AM, Gotmachine said:

If your goal is to make self-sustainable bases, yep, it is hopeless. In fact, even doing "basic" manned missions outside of the Kerbin SOI is quite hard.

Kerbalism difficulty balance make what is achievable in KSP roughly in the realm of reality.
I've yet to see proof of a successful manned mission to Jool with Kerbalism. And I believe that there are only a handful of people that can claim a successful mission to Duna.

Well, that's one more reason to try.

To make my mission reports easier to navigate, I'll try to organize stuff into collapsible chapters.

0) Why refueling only at Duna? Considerations on Kerbalism ISRU

Spoiler
ISRU in real life is difficult. In kerbalism, it is made even more difficult by ignoring the most convenient route, plain water electrolysis into LH-LOx. 
Quote

We consider ore to be generic regolith (because it is available everywhere). The carbon content of regolith is usually ridiculously low. Less than 100 ppm on the moon. There are potential localized source of carbon rich minerals on mars, but we simply ignore that.

In kerbalism, liquid fuel is methane, and methane requires carbon and hydrogen. Hydrogen can be obtained from water electrolysis at a high, but manageable, electricity cost. But since the mod does not account for carbonaceous ore, there is no practical way to mine carbon. The only way to produce it from ore is by Molten Regolith Electrolysis. But this process is too expensive to be practical: it takes 450 electricity to make 1 unit of CO2, and 7000 CO2 to make a single unit of fuel.

With a ship of my size, I need at least 10 tons of fuel per day to refuel practically (and even that would take the best part of a year); to get that, I’d need 300 million electricity. Which would be over 10000 per second. Make it 20000 because half the time will be night. And I’d need to sustain that far from Kerbol too. Impossible.

But there is a shortcut that you’re supposed to be using: harvesting CO2 from an atmosphere. Which can only be done at Duna (and Laythe, but it’s too expensive to get away from it to make it worthwhile. And let’s not mention Eve).

Even on Duna, though, it’s crazy to get the amount I need. One spectrovariometer in atmospheric harvester configuration can get 0.2 CO2/second. Long story short, to make my 10 tons per day I’d need 1600 spectrovariometers, plus 80 water drills and 320 gigantors to power up the whole thing, mostly for water electrolysis.

Getting those numbers would be potentially possible with a Duna base. But not in the game. Can you imagine 2000 parts on the ground? The kraken would feast upon them before they can even be remotely complete.

But I could, in theory, do it. So I’ll just pretend that I sent a big base on Duna to produce all the fuel I need, and that the “easy” ISRU comes from there.

Even I am not so crazy as to try a 2000 parts land base.

And if I wanted to make things easy, using drop tanks would be more convenient. Perhaps a cluster of 500 ion engines.

Part 1: Projecting the DREAM BIG

1.1) Home mothership

Spoiler

This is my mothership. Its purpose is to keep my kerbonauts healty and sane for decades, and to provide plenty of fuel for the various missions. I called it Home, because that’s what it is: a home to live in for a spacefaring race. I needed plenty of living room for everyone. And every system had to have multiple redundancies. And of course all those things will be very heavy, so I will need a crapton of fuel to keep a decent deltaV.

Then I must power up life support; I can’t use RTG because radiation will be already an issue without adding to it. I need panels, even at Eeloo. And I need greenhouses. Yes, it would be easier to just add some 10 tons of canned food, but what the hell, you’re not conquering space until you become mostly self-sufficient. So, it takes 2 greenhouses to feed a kerbal, I need 24. And better to keep some extras, especially after I realized I won’t be able to work them all around Eeloo. I need some extras to restock supplies when I can. So I have 32 greenhouses. But those greenhouses consume a lot of electricity. I’d need over 100 gigantors to provide for them in the outer solar system. I actually tried to fit all those panels around my ship, but they caused too much stress on the girders. In the end I settled for the most I could fit without causing too many structural problems; 64 panels.

Together with the four giant S4 fuel tanks, those make the most of the station. It then has a bunch of amenities, like multiple research labs, gravity rings, cupolas, that are not strictly needed (I’d only need one to get the bonus) but I’m including anyway because I want this thing to be nice. There are 12 medium docking ports and 4 small docking ports, plus a small port on the front for asymmetric loads (basically, the Eve lander). I thought that was overkill, but I ended up using all of them.

Everything has maximum radiation shielding, of course, and there are also 4 active shields; both too many and not enough. TWR is 0.13 fully loaded, which is not too bad for this kind of vehicle.

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Cost: 1,61 million + 2,20 millions for the launcher.

1.2) Dolphin escape pods

Spoiler

So, Home should be all safe and snug. But say one of my kerbonauts has a nervous breakdown. Or has radiation poisoning. Or too many solar panels broke and I can’t feed everyone anymore. Or too many engines break and I have to get back to Kerbin.

For those eventualities, I designed an escape pod. I called it Dolphin because dolphins occasionally help shipwrecked sailors to the shore.

It can’t have too much comfort or life support, especially radiation resistance, so I wanted to keep travel time short; 1 year to reach Kerbin, from any place and time in the solar system. This can’t be achieved while waiting for transfer windows, so I loaded some ion engines with 11 km/s of deltaV available. It can force an intercept from anywhere in 1 year, and it has supplies for three.

It will also produce a high speed intercept, so the reentry capsule must be able to withstand it. I tested it at up to 7 km/s, and heat is no problem – the limiting factor becomes acceleration.

To further stretch the range, when arriving near Kerbin i will dump the living space and spent xenon tanks, gaining some more deltaV to slow down to a manageable speed.

Each of those can evacuate three kerbals, so I'm carrying four.

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Cost: 290k + 30k for launcher, *4. Most of that is the Xenon

1.3) Digger mining vehicles

Spoiler

Those refueling vehicles are the backbone of my mission. I can’t go far without them. After calculations, I realized my crew would have to spend quite a lot of time inside of them, so I decided to put some extra comfort; living space, cupolas, an active radiation dampener. It carries an exaggerate amount of drills because those are less effective in kerbalism.

I also included smaller drills for water and nitrogen and a CO2 atmospheric harvester, I should not need them but I prefer to have the capacity for it. Since they will only be used on Duna, I included parachutes, though of course it needs rockets to slow down in the end. They carry 4500 m/s and will need some 1500 to go up and 500 (safety included) to go down. Hopefully that will translate to 50-70 tons of fuel left that I can transfer to Home. I will need dozens of trips. I am not looking forward to that.

Both to speed up operations, and because they are at high risk of breaking, I am carrying 4 of them.

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Cost 418k + 512k for the launcher, *4.

1.4) The Can lander

Spoiler

A simple lander. Minimal comfort, the crew is not supposed to stay inside more than a day. It can couple with a Digger for greater range, and it can attach to an extra stage for Tylo. I’m only carrying one of those, so I gave it plenty of engines for redundancy. In the worst case, though, I can still use a Digger to land anywhere.

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Cost: 61k + 10k for launcher. Most of it is the high quality life support and the science instruments. An additional 20k for the Tylo stage, + 162k for the Tylo stage launcher.

1.5) FU Eve lander

Spoiler

This is when I realized I really hate Eve.

I spent a month trying to make an Eve ssto, and failed. To date, that’s the only challenge I tried that I really failed.

Ok, I will use multiple staging. I had devised, for a previous challenge, a spaceplane that I used to reach the inner layers of Jool. From there it must reach 6000 m/s orbital speed, and it does so with 1000 m/s to spare. And it survives a Jool reentry, of course, to get there first.

I tried that model on Eve. Eve trashed it effortlessly. Really. You’d think reaching inside a gas giant would be the bigger achievement. Nope, Eve is still much harder than that. My Jool spaceplane didn’t even come close to it. Despite 6000 m/s, despite using propellers to reach 8 km of altitude and clear some atmosphere, it didn’t get to orbit. Worse, it didn’t even get suborbital! Not even after I loaded a couple extra engines to increase TWR.

And by the way, I don’t like spaceplanes. Why do I keep finding myself making some?

So, at some point I decided I had enough. I tried to go nice, and it failed. I tried to go fancy, and it failed. This time, I’ll just go big. I’ll defeat Eve by throwing stuff at it.

And I made this massive thing, at over 400 tons, with 8 inflatable shields and a bunch of wings to keep the whole thing pointing the correct way during reentry. I still had to try an inordinate amount of times to get this right. And then I had to face further hassle because those wings on top kept capsizing me at launch.

I called it FU Eve (the meaning of the acronym is left to the reader’s imagination) because I had ENOUGH of that goddamn planet.

The last stage of this vehicle is a readapted version of the Laythe lander I used in my no contract career challenge. I liked that rocket and was looking for an excuse to use it again, so I did.

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Cost: 646k + 90k for launcher. Most of it are the massive mammoth engines and fuel tanks

1.6) Trucker Moho transfer stage

Spoiler

I won’t have enough fuel to get to Moho and back, and I can’t refuel there. And I won’t use drop tanks. So I designed a one-off small spaceship to carry crew to Moho. No, don’t ask me how is this any better than using drop tanks. It’s not even cheaper, since I’m spending over half a million on xenon alone.

Anyway. Comfort enough for a few months. 13 km/s with ion engines to get there regardless of orbital mechanics. It will get coupled to The Can lander, which will make the actual descent. I completely forgot to put some heat radiators on it, but I run some experiments and it works without. Seems like a weakness in the mod.

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Cost: 660k + 37k for the launcher. Most of it is xenon

1.7) Wing reconnaissance probes

Spoiler

The initial plan, when I still thought I could refuel anywhere and I could take my time exploring, was to have a flotilla of those. I would detach them and send them on polar orbits, detecting all anomalies. Being unable to refuel away from Duna, and being forced to go fast at Jool because of radiations, put a wrench into that plan. Still, I included a couple. Why not?

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Cost: 130k for both Wings and the launcher

1.8) DREAM BIG, fully assembled (and musing on realism)

Spoiler

Total cost of all the ship is 11,73 millions, including 1450k for the final refueling. Finally an adequately funded space program!

The full ship has almost 1200 parts, and weights 3600 tons. When I load it, my pc takes upwards to a few minutes. When I use it, I get maybe 2 or 3 frames per second.

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And it’s beautiful. It gives me the chills when I perform a spacewalk amid its multiple docked shuttles and I really realize how incredible this creature is. It's the "quit ksp aterwards because you realize you'll never be able to top it off" kind of achievement.

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Let this stand as my argument for realism. I’ve been told that such a mission can’t be done, because the mod is about realism and we wouldn’t be able to do this in reality. But I contend that we would actually be able to do it, if we had this kind of resources. Because this marvel would be, what, twenty times more expensive than the whole Apollo program? Fifty? And of course it would be less efficient than sending individual missions to single planets. But we could actually do this, if we really wanted. Let others play rehearsals of real missions; I’d rather read about those in books. This game is a canvas for our dreams, and I want to DREAM BIG

1.9) Analysis: reliability and redundancies

Spoiler

The DREAM BIG will stay in space for up to 15 years. A lot of things will break in that time, and I must make provisions for that.

Home itself has so many redundant life support systems, I didn’t even bother to make them high quality. Same for solar panels, I will lose some along the way but it’s all right. I didn’t make them high quality because they’d be 50% heavier, I’d rather pack more solar panels to have some spare.

I have 12 wolfhound rockets in a twofold symmetric distribution. If I break one, I can shut down its opposite and keep going. I can lose at least 3 engines without too much trouble, more if they are not all on the same side. And of course I have engineers on board to fix all that can be fixed. No problems here.

The various shuttles are a bit harder, I cannot afford the same level of redundancy, though wherever I could, I made sure they could survive with a broken component.

The Dolphin escape pod has 6 gigantors and 2 ion engines. I assume it can keep going with just 1, its reaction wheels keeping it pointed in the right direction against the asymmetrical push, but i’d rather not have to find out. There is only one antenna, but that’s not essential for the mission.

The Can has 16 engines, it can lose some. The Tylo stage is a bit more delicate, but I made sure it can lift off with one engine down (and its symmetric shut down). But I will have to use that only twice, and those engines are all high quality. I also stocked emergency fuel cells in case of power loss, and at least 3 reaction wheels. Those things are safe.

There are two factors worrying me, though.

The first is the FU Eve. It’s a single point of failure. If an engine breaks while I am on Eve, the crew is dead. Nothing to do, period. Making an Eve rocket is hard enough already without trying to make one that can work without any one of its engines. But I only need to use it once. To further mitigate risk, I will have an engineer on board, and when I lift off, I will first start the engines slowly. So if one malfunctions, I can still shut off everything and repair it. A critical failure will leave me dead on Eve anyway, but not a malfunction.

The second and third stages, instead, will definitely leave my kerbnaut dead even in case of a malfunction. A high quality rocket has a 0.2% chance of malfunctioning, and one accident in four will be critical (if I interpreted things correctly). All things considered, I have 99.4% chance of everything going well. Good enough.

The last stage of FU Eve will also be used on Laythe, as SSTO. Again, there is a single point of failure. Let’s say I will turn on the engine a few times for manuevering, there is maybe a 1% cumulative chance I will lose it before landing. In which case I will skip Laythe and continue the grand tour. It can still be a partial success. If I lose my engine on Laythe, my Kerbonaut dies. It can happen twice: first to slow down descent (the parachutes slow me to around 15 m/s, if the rocket malfunctions it crashes; the kerbonaut probably lives, but is stranded on Laythe with no hope of rescue and will die by radiation poisoning). And then to restart.

Accounting everything, there is roughly a 3% chance that something with FU Eve won’t work. I have to accept this risk, because I spent two weeks drawing vessels, and I am too tired to keep at it.

My second main worry are the Digger mining vehicles. I made sure that each of them can fully function with one engine down. But I will use them a lot of times. I don’t want to try to calculate the odds there, but I’m pretty sure two engines broken are likely. My contingency there is to bring 4 of them. And even in the worst case scenario, the crew should survive and be available for pickup by another Digger. Having 4 of them also let me relax about breaking a convert-o-tron. If I lose 3 of them and the last one is one engine down, I will scrap the mission and limp back to Kerbin with whatever accomplishment I managed.

1.10) Mission plan

Spoiler

Having decided to refuel only at Duna, I must plan the mission around it. I have 4000 m/s available. 4500 if I really squeeze it. That’s not enough to reach Moho and come back, hence the Trucker stage. Drop tanks could do the trick, but I want my mission to be as reusable as possible.

So the DREAM BIG will go to Eve, where it will drop the really big lander. From Eve I will send on the Trucker, while Home will wait in orbit, maybe around Gilly. After the Moho stage comes back, DREAM BIG will go to Duna and refuel. This should take a couple years; I will try to minimize time at the cost of slightly more expensive trajectories.

From Duna I will launch to the Jool system. There I will park Home around Pol, well away from the deadly radiations of Jool, awhile the shuttles pursue different targets. The Can, coupled with a Digger for extra range, will land on Tylo and Vall. FU Eve, coupled with another Diggger, will go to Laythe. A third Digger will go to Bop. Then back on Duna for refueling. I hope to make this second part in 3 years.

At this point I’d miss only Dres and Eeloo; ideally I’d make both in the same go, but it will really depend on orbital mechanics. I’d hope to make 1 year travel time, for a total of 4 years, but that’s optimistic. So, in the best case, the mission should take 10 years, but the DREAM BIG should be able to stretch to 15.

1.11) Goals and success

Outstanding success!

Grand tour is completed successfully; DREAM BIG returns to Kerbin and it’s mostly in good conditions, ready to make the trip again with minimal resupplying.

Complete success!

Grand tour is completed successfully, and all the crew returns home in some way.

Partial success!

Grand tour is mostly completed, but one or two planets are skipped. Some inconvenience forces me to cut the mission short. All kerbins are safely returned home. Example: Time and malfunctions force me to skip Eeloo and Dres.

Mixed success

One or two kerbal die on the mission. The mission still reaches most of its objectives, though. Example: FU Eve explodes during reentry, killing a kerbonaut and forcing me to skip Eve and Laythe landing, but the rest of the mission goes fine.

Mixed failure

As mixed success, but with more casualties and/or more planets skipped. Example: FU Eve explodes, and I also have to skip Eeloo.

Partial failure

Several things go wrong; many kerbonauts die, and/or the tour fails to reach even half of its intended targets. Still there are some highlights to justify this not being a complete failure. I must at least reach Duna to qualify for this.

Complete failure

The tour doesn’t even come close to completion, and/or there are lots of casualties.

To make an ass of myself

I lose all the crew without even going far towards completing the objectives

This is the first time I perform a challenge I'm not sure I can succeed at. Heck, I'm not even sure it can be succeeded in the first place. How well will I fare?

Edited by king of nowhere
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Part 2: Assembling the DREAM BIG

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When I started this task, I wasn't even sure it would be possible to make a ship as big as DREAM BIG without it getting eaten by some kraken. Especially because kerbalism seems to have some conflict with autostrutting. Thankfully, all went well. Eventually.

Spoiler

First I launched Home, with all the 12 crew members. I brought so many to have spare crew members if I must send some back on a dolphin.

Home is by far the biggest thing I ever launched.

"Originally the result of a unit of measure conversion bug, the S4 series of fuel tanks transcend the preposterous into the truly absurd. When 'More boosters' fails and is replaced with 'More engines!', the S4 series tanks will be there to loft your dreams, no matter how ridiculous and over-engineered, into the sky on massive trails of fire."

"I'll buy a dozen of those. For the second stage"

It was a real challenge, because in addition to its mass, it also has several delicate parts that prevent a simple asparagus stack. I lost counts of how many early trials I blew up on the launch pad

It took 28 mammoths to lift this thing.

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One of the most spectacular failures involved some of the launch stabilizers getting clipped inside some fuel tanks. On such a big assembly, it's easy to miss. When I activated staging, the clipped struts were no longer part of the same vehicle, hence they were no longer allowed to be clipped, and everything went kaboom!

Since I'm using kerbalism to simulate possible accidents, I wanted to make this launch safe (not counting experiments blowing up on the launch pad, of course). So I started the engines slowly; in case one malfunctioned, I could still shut off everything and repair the damage. Also, I planned for the launcher to keep flying even if one engine broke; luckily, I didn't have to test whether it would have actually worked.

The launch was most awesome!

The following pictures are taken from several different launches, that's why in some scenes it's night and in others day, and in one picture Home has only 8 rockets instead of the 12 of its final version.

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Lift off! It's actually rising in the sky! It's actually not exploding this time!

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With a ship this big, gravity losses are much bigger than aerodinamic losses. So, a steep gravity turn it is, even if it means going very fast in the atmosphere with two ridiculously draggy things in front

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First stage separation

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Second stage ignition! Also, deploying solar panels, since I'm now in space (bless whoever introduced action commands or I'd have to deploy each one individually)

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Second stage separation

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Orbiting!

 

Launching the Dolphins was pretty straightforward

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Now the Diggers!

Those are more complex, having a 3 stage launch system. I could have used their own rockets, but I wanted to keep their fuel. I will need to launch DREAM BIG fully fueled anyway

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Here kerbalism makes its first kill! An engine malfunctioned, sending the whole rocket into a spiral. I could have saved it if i shut down the engines promptly, but I wasn't ready. Anyway, it was just an unmanned launch. Add 900k funds to the total cost and build another!

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I've never seen this effect before kerbalism, so I assume it has something to do with the pressurized gas tanks. It's beautiful, though

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And here we have the first kraken victim! The lower fuel tank partially detached along the hinge. Though not sure how much it can be kalled a kraken and how much inadequate structural stability. Anyway, I scrapped this Digger and I added some struts to the design.

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Assembly begins

Home, by itself, is 330 parts, and the cpu still manages. Each Digger is adding over 100 parts, and the game is lagging more and more.

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Here we have a second kraken victim! I had to autostrut those parts during launch, or they'd fall off. But kerbalism+autostrut tend to cause those scrambled attachments. I don't know if it can even be prevented, but it's non fatal, so I keep the ship like this.

But the kraken has much worse in store: the shacking, that accompanies all sufficiently big ships and threatens to tear them apart. Here it ripped one of the main tanks.

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And here it ripped off a piece of tank (harder to notice in the night, but the tank on top left of the image is floating freely, and it's not supposed to).

I was reluctant to use autostrutting, given the previous problems, but I was convinced of its necessity, and a small, carefully applied use of it was enough to stabilize the DREAM BIG. As of this writing (I'm orbiting Eve) I didn't have further problems.

 

Next the Wings. The game is now taking over a minute to load every time DREAM BIG enters physical range. To reduce this time, I decided to send both Wings in a single package. Designing the launcher probably costed more time than it saved, but whatever.

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The most observant may realize that there is no spaceing between the Wings body and the cargo bay. Indeed, they got attached from the fuel tank instead of the docking port, and now cannot be detached. I had to send up a new one :/

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Starting to get crowded here

 

Now comes the Tylo stage

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And the Trucker Moho stage

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I'm definitely having a hard time docking those final pieces without bumping into anything

The Can lander

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Finally FU Eve for last, as it is the single piece with the highest parts count (except Home, of course); the amount of strutting on it is incredible.

This thing was a bit challenging to launch, in that the huge wings on top are needed to keep it stable while it's aerobraking in Eve's atmosphere, because those wings have a very strong tendency to go in the back. Unfortunately, they manifest this tendency also during launch, when I would want them to stay in the front. Ultimately, I resolved to launch with a very low TWR and just try to keep the flipping force to a level that the engine gimbaling could compensate. Unlike other vehicles, I also decided to have a minimalistic launch vehicle and use FU Eve's own fuel to reach orbit; I was already planning a refueling mission.

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8 inflatable thermal shields and 8 500-kg wings, but I still put in the effort to place a nose cone at the tip

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Docking was very tricky: I had to stick a 400 ton ship with a 3000 ton ship using a clamp-o-tron jr. I had to be very, very, very soft for contact. Good thing Home has an RCS system (at least in 4 directions, the remaining two got deleted accidentally during some of the many revisions). Even so, the two parts bounced and then, sloooowly, they touched each other at a wrong angle. I put the game in background and went to do other things. It took several minutes for the small pull of the clamp-o-trons to turn the ships around enough for docking.

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The mammoths are only rated for one ignition, two if high quality. After using them, I send an engineer for refurbishing. At this point I really realized the ludicrous size of this spaceship I'm building

I'm doing a lot of waiting with DREAM BIG; as it takes several minutes to load in most circumstances, I usually put ksp in background and play a chess game. Incidentally, my lichess rating is taking a blow, as I don't have full concentration during those matches.

Finally, it's time for the refueling flight. There is only 1 medium docking port left free, and all around it it's cluttered with other shuttles. I decide to make something with a very long, thin nose to reach inside all those obstacles more easily. It ended up looking like a syringe. It also has a syringe's purpose.

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Kerbalism hit hard on this one. I can understand the mammoths, but the thuds are rated for a dozen ignitions

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This last stage has only RCS. Even though I had 6 vernor pointing forward, It still was painfully sluggish. The lag from the 1200 parts of DREAM BIG contributed. Docking was very difficult. 

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Coupled with another 400 ton ship, for a little while DREAM BIG was EVEN BIGGER!

All in all, I docked 14 parts (4 Dolphins, 1 Trucker, 4 Diggers, 2 Wings, 1 Tylo stage, 1 The Can, 1 Syringe). With the lag, loading times, and general difficulties with parts so big - and occasional accidents with krakens - it took me two days of hard playing. I'm almost reluctant to actually fly. What if, after all this effort, the DREAM BIG won't do as well as I hope?

Edited by king of nowhere
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Part 3: False starts

No matter how extensive the testing, upon actually performing a mission you will always realize you were missing something. Here I reach Eve, Gilly, Moho before realizing I have to reload all the way to the beginning. DREAM BIG performs nicely, but the flight plan is faulty.

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the DREAM BIG is about to explode during an overly optimistic attempt to aerobrake at Duna

Spoiler

I should have expected something to go wrong. I didn't because I had absolute faith in my ship and all the testing I did there.

In fact, the problem was not the ship. The problem is, I've never been to Eve and Moho before.

It's very strange. I've done multiple Jool 5, I've launched missions past Eeloo's orbit, I raced thousands of kilometers on rovers, I even landed on Dres three times. But never Eve and Moho.

I actually launched a lot of missions to Eve back when I was playing a career; but I got bored of the career after about 200 days (after I had missions to every single planet, 13 million funds, and I just had to wait for everything to arrive). So, none of my missions actually went to Eve. And they all had ISRU for Gilly anyway; it's a lot easier if you can refuel at Gilly. And I spent a month testing an attempt at SSTO, which ultimately failed, but in all this time I was flying on Eve but I didn't get there. I also had a giant ship land there for a contract, but it had ISRU and it used rocket braking. And I stopped playing before it reached Eve anyway. Also, I didn't have to worry about radiations. Or about launching out of a window because your crew is slowly being killed and you don't have the luxury of waiting one year.

Speaking of that, I didn't knew exactly what radiations would do. I assumed, since I was using the maximum shielding, and I had 9 active shields on my ship, and I was being careful to avoid radiation belts, that I would be fine. I took all possible precautions, no point worrying more. Well, wrong on both counts. But let's go with order.

The travel starts with ill omens. On the very first day of flight, Jeb's stress value suddenly jumps to 2%, and he has a breakdown and smashes a radiator. Nothing an engineer can't fix, but c'mon, what the hell Jeb?!?! You're basically in a flying luxury resort, and you've been there less than 24 hours anyway!

Besides this minor accident (which, if nothing else, proves that the ship can deal with accidents) I launch regularly. Instead of slowly raising my apoapsis with the low thrust main engines - a manuever that would leave me exposed for days to the radiation belts - I opt for using the big mammoth engines of the FU Eve to propel the ship quickly away from dangers.

The trip took 200 days, mostly unremarkable. At least, nothing I can do anything about. But I keep seeing radiation symbols popping up. I eventually discover it's solar storms; they are almost once per week, and they got my crew to 20% radiation damage. Also, the crew stressed very easily; most of them are now past 30%. Despite, I repeat, living in what is basically a flying luxury resort. That's a lot of damage, for less than half a year. It seems my plans for a multi-year missions won't work after all?

Well, if that is the case, I refuse to count it as a failure. A challenge is such if you can do something towards the result; you have an apparently insurmountable obstacle, but you can get creative and maybe the obstacle is not so insurmountable after all. However, if you cannot do anything, then there's no challenge, no sense to it all. And I already did all I could about radiations. Unless... I have 3 options about it:

1) Rebuild the DREAM BIG and add 100 active shields to the ship. Those should be enough to negate solar storms. They'd also add 250 tons, which is some 25% of the ship's dry mass; actually feasible, if uncomfortable. And I can always add more tanks and engines.... The more I think, the more I am leaning in that direction. I could also very conveniently call it DREAM BIGGER. My main problem is with parts count getting even worse.

2) Change crew. The DREAM BIG can survive decades; the crew cannot? Just make a fast shuttle, bring in a new crew at Duna, bring the old crew back. A bit clunky. The main problem is, I'm not sure I can do it reliably without getting anyone killed by radiations; I reached Duna after one year of total mission with 80% radiation poisoning on some crew members, I'm not sure they'd survive the trip back. Or the longer trip to Jool.

3) Cheat. I discovered that radiation and stress damage only happens on the ship you're actively controlling. That's clearly not intended by the modders, and it would be cheating.... except that the whole crew dead in less than 2 years despite the best shielding available is also something that should not happen. Two wrongs don't make one right, but sometimes they cancel each other.... I'm definitely considering it. But it wold definitely hurt my bragging rights.

EDIT: I later discovered that the mod keeps track of fuel tanks and other heavy parts offering radiation shielding, and that's how you would be supposed to survive solar storms, by pointing the heavy parts of your ship towards the sun to protect your crew. But I didn't knew at the time; it seems kerbalism has a discord channel as its main lobby, and asking questions in the thread here won't get many answers. /EDIT

 

Then I reached Eve. I was, of course, in a very eccentric orbit, because circularizing around Eve would be too expensive. From there instead I went to Gilly with a 500 m/s manuever. I did so because I figured I'd be more protected from radiations (Eve's magnetosphere is too tiny unless I circularize, and if I did, I wouldn't have the fuel to leave). My plan was to wait around Eve, while the Moho stage did its trip.

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The manuever to reach Gilly

But this was a mistake. My elliptic orbit was already angled pretty well for reaching Duna. By going to Gilly and back, I spent a lot of fuel I didn't have to. I didn't even get much radiation protection, as far as the mod is concerned I only was in shadow of Gilly some 20% of the time. Most important, though, the correct course of action would have been to leave Eve for Duna after a couple of weeks, just the time for the Eve lander to do its tour. Duna and Eve were in the right position for a transfer, and the Moho stage can go back to Duna just like it can go back to Eve.

I still had plenty of fuel, but it turned out, upon reaching Duna, that I didn't have enough to brake. I learned in the past that I can always aerobrake safely on Duna. I now learned that I can't do it when I have an intercept speed of 1500 m/s. I managed to slow it down to some 800 m/s with my remaining fuel - back in the day when I attempted this manuever with the Marco Polonium, it worked. Unfortunately, the DREAM BIG is larger and more fragile. The main ship could indeed survive the manuever with that intercept speed, but it lost all the gigantor solar panels.

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Too much intercept speed, too little fuel

But that would happen later. In the meantime, I sent out the Moho stage and I landed the FU Eve.

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the main craft split threefold. In purple, DREAM BIG is heading for Gilly. In yellow, Trucker is preparing the first burn for Moho. In white, FU Eve and Digger 3 are gradually aerobraking

Landing was harder than it was in the tests, because I started with more speed - I had to reduce it during several aerobraking passages, which I did while coupled with a Digger because FU Eve doesn't have enough life support on its own, nor does it have the deltaV to reach Gilly after orbiting. I managed, sort of. Getting away from Eve, instead, was much harder. Despite the giant wings on the bottom, my ship kept trying to flip. Perhaps it was the spent parachutes on top that I could not repack? Can't think of anything else, in the tests it was going great. Anyway, I should eliminate them after landing, they are extra weight. It took me some 20 tries before I figured out exactly how to take off from Eve. Yay! But if I can improve things, I will.

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Fu Eve coupled with Digger 3

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With 3 diggers, the DREAM BIG is asymmetric. After some trial and error, I align center of thrust with center of mass by shutting down two engines and shifting some fuel in the main tanks

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Giuritto inspecting all the systems on board before separation

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The various stages of descent, shedding the various parts. No pictures of ascent, I was too busy trying to steer the ship. Also, next time I'll try to do it in sunlight

Meanwhile, since I was staying at Gilly for a couple of weeks, I decided to send the Diggers down to get some carbon dioxide through the molten regolith electrolysis, I was running low on it for the greenhouses. There I discovered several things:

- I intended two of my Diggers to have small water and nitrogen drills. But all those drills were water! Granted, I should have plenty of nitrogen and ammonia and not need any for the whole mission, but being self sufficient would make me feel better.

- I can't make monopropellant with the convert-o-tron. I still can make LF-Ox, but not monoprop. No idea why. Anyway, I need monopropellant for EVA, of which I need a lot to repair the spacecraft. Again, I should have enough for the whole trip (maybe -  not so clear cut as the nitrogen), and again, I'd feel better if I knew I could make more.

- I missed a step on the ladder, so I cannot use it. I can fix it, or I can remove it for reduced part count. If I can make monopropellant again, there's no more reason to be stingy with EVA

All small things, but all would make me wish I could go back to the workshop and fix them.

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Some pictures from Gilly

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Wings 1 detaches from the DREAM BIG to collect science. The experiments will fail for practical reasons: they require low orbit, which on Gilly is below 6 km, and there are many peaks higher than that

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This explosion was not caused by a mistake of navigation, but by a glitch of speeding up time. Low gravity meant I had the time to snap a picture while there were still enough debris around

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During this time I suffered a critical failure on Digger 3 engine. The possibility was well accounted for, it can still take off from Duna, and I have 3 extra

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At some point I even tried to land the DREAM BIG to protect it from storms. It didn't work.

The last nail, though, came from the Trucker Moho stage.

- with 4 engines, it has an acceleration of 0.2 m/s. It needs some 7000 m/s to reach Moho outside of a perfect window, that makes it 10 hours of burn. Which I did with the game in background while I was reading a book, but anyway, adding some engines would be good. And same with the dolphins

- Most dire, I packed 13 km/s thinking there's no way they would not suffice. It took 7 km/s to reach Moho, and Moho-Duna is another 7 km/s. Take away 1 km/s from a very optimistic aerobraking, it's still huge. 5 km/s of ejection burn. And it will be worse, with that low TWR. And my deltaV got reduced for being coupled with the Can lander. All this together meant the Trucker could not do its job and needed more fuel. Ouch.

EDIT: Now that I have a lot more experience going to Moho, I can't believe how inefficient I was being here. My past self can be somewhat excused because the radiation clock was ticking /EDIT

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The Can couples with Trucker amid the other shuttles

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As you can see, I start with two thirds of my fuel supply. Kerbalism provides some really big xenon containers, but I assumed it would be overkill filling them all.

Really. I am piloting a 1200 parts, 3600 tons ship, and I worry about overkill for a couple tons of xenon. Of course it wasn't enough, and I did deserve that.

The deltaV shown there, and in all other pictures, is obviously wildly inaccurate.

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Some of the super expensive manuevers required

Eventually, instead of trying to salvage the mission, I decided to go back to the very beginning and fix all those small problems I discovered along the way.

Some may say that I should not have jumped straight away for the big target, that I should have learned the mod gradually. I'd reply that I learned it much better by going for the big target.

Edited by king of nowhere
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What about using a bunch of Aldrin Cycler-esque designs which go between the different planets?  For example, you could have one that goes between Kerbin and Duna, say with a crew of 8 (although the ship would need to support 16 for safety reasons). When the ship first arrives at Duna, the crew would land at a prebuilt base, and any existing crew would be picked up from the surface to take back to Kerbin. Then, back at Kerbin, a crew shuttle would be sent up to the cycler, where the crew from Duna would return home and a new crew could head towards Duna. Then, at Duna, depending on the transfer windows, you could have another cycler going from Duna to wherever works best next (say Dres). A few of the crew from the Kerbin-Duna cycler could wait on Duna until the Duna-Dres Cycler makes it to Duna, and then board that cycler to land on Dres. It would take a bunch of surface bases and giant ships, but I think it would avoid a lot of the stress problems and a lot of the problems with solar storms, since the crew would mostly be on the surface of different bodies.

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Check your Kerbalism settings and turn the solar flare frequency down- as in way down- as IIRC Kerbalism has a bug in it which makes solar flares far too common and will irradiate your crew pretty quickly. You could also try turning the ship so the engines point at the sun which provides some measure of shielding to the crew compartments, then switch away from the ship during your travels so the game thinks it’s still pointing that way.

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7 hours ago, Yosir the Joolian said:

What about using a bunch of Aldrin Cycler-esque designs which go between the different planets?  For example, you could have one that goes between Kerbin and Duna, say with a crew of 8 (although the ship would need to support 16 for safety reasons). When the ship first arrives at Duna, the crew would land at a prebuilt base, and any existing crew would be picked up from the surface to take back to Kerbin. Then, back at Kerbin, a crew shuttle would be sent up to the cycler, where the crew from Duna would return home and a new crew could head towards Duna. Then, at Duna, depending on the transfer windows, you could have another cycler going from Duna to wherever works best next (say Dres). A few of the crew from the Kerbin-Duna cycler could wait on Duna until the Duna-Dres Cycler makes it to Duna, and then board that cycler to land on Dres. It would take a bunch of surface bases and giant ships, but I think it would avoid a lot of the stress problems and a lot of the problems with solar storms, since the crew would mostly be on the surface of different bodies.

Do astronauts not get stressed if they are on the ground, even another planet? I don't know those fine nuances of kerbalism.

anyway, cyclers won't help me with radiations. and finding a proper orbit for them would be a nightmare. and i'm not even sure how well they would survive space. i built enough redundancies on the DREAM BIG that i am confident it will last decades. but if i make cyclers, either i make each one of those as big and complex as the DREAM BIG, or i risk them breaking up after a while

4 hours ago, jimmymcgoochie said:

Check your Kerbalism settings and turn the solar flare frequency down- as in way down- as IIRC Kerbalism has a bug in it which makes solar flares far too common and will irradiate your crew pretty quickly. You could also try turning the ship so the engines point at the sun which provides some measure of shielding to the crew compartments, then switch away from the ship during your travels so the game thinks it’s still pointing that way.

does turning a ship really helps against radiation? again, those fine nuances aren't written anywhere.

since you guys seem to know stuff, i take the chance to ask: do anything drastic happens when stress reaches 100%? because if the only problem is some extra stuff breaking up, i may be able to make it.

as for reducing the frequency of flares - and indeed, they are too frequent - it still would feel like watering down the challenge. anyway, i decided to tackle the radiation problem by brute force. a solar storm is on average 5 rad/h. an active shield prevents 0.04 rad/h. so some 120 active shields would negate a solar storm completely. they weight 300 tons, but I figured my ship was already 3600 tons, it wouldn't matter all that much.

Edited by king of nowhere
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@king of nowhereyou do realise those shields use a considerable amount of power? 120 of them would require a nuclear reactor to run them all as (if I remember the numbers correctly) each one needs ~4EC/s to run so you’d be looking at 500EC/s for them, or the combined output of 22 Gigantors at Kerbin, so utterly impractical anywhere further out.

I suggest you use some Hitchhiker cans which have radiation detox units in them and so can ‘cure’ radiation exposure for some power and extra oxygen use, plus they have TVs which can help with stress; those modules only work for Kerbals inside them though.

Spoiler

I’ve never actually seen either the TV or RDU having an effect on Kerbals so can’t say for sure that they both work as advertised. Letting your Kerbals get over stressed just means each one will break something when they hit 100% and if they start crippling engines or life support modules you’ll be in big trouble pretty quickly.

 

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1 hour ago, jimmymcgoochie said:

@king of nowhereyou do realise those shields use a considerable amount of power? 120 of them would require a nuclear reactor to run them all as (if I remember the numbers correctly) each one needs ~4EC/s to run so you’d be looking at 500EC/s for them, or the combined output of 22 Gigantors at Kerbin, so utterly impractical anywhere further out.

I suggest you use some Hitchhiker cans which have radiation detox units in them and so can ‘cure’ radiation exposure for some power and extra oxygen use, plus they have TVs which can help with stress; those modules only work for Kerbals inside them though.

  Hide contents

I’ve never actually seen either the TV or RDU having an effect on Kerbals so can’t say for sure that they both work as advertised. Letting your Kerbals get over stressed just means each one will break something when they hit 100% and if they start crippling engines or life support modules you’ll be in big trouble pretty quickly.

 

for the energy cost, I have 64 gigantors on the main ship alone. plus 4 fuel cells packs. plus additional fuel cells on all the shuttles. and I can shut down the greenhouses during the storms, and I only need to keep it up for a couple hours. perhaps i won't be able to sustain the shield around jool, but i will definitely be able to keep it up at least until dres. And then it will still cover me most of the way towards jool. only close to jool i may have to shut down a few of the units after a while, in which case the shield is still helping. and at jool i'll be proctected by the magnetosphere

for the hitchicker, i have them, and i haven't seen any effect from them. i had one kerbal inside one of those, and i didn't notice anything different. also, greenhsouses should give bonus to morale with plants, but they don't. the game is still telling me i have no plants. so, not everything in the mod is flawless. it may be the mod malfunctioning.

as for stress, i have 12 kerbonauts, so I am looking at 12 accidents. of those, more than half will be fixable. and aside from a critical failure of the engine of the FU Eve lander, there is absolutely nothing that will hinder me. i have 32 greenhouses, each one of them has pressure control, and a good dozen other habitats, each with life support, and all the shuttles with 2 to 4 redundant life supports. I have 64 solar panels. The new version has 22 engines (and if i somehow were to lose them all, i could couple a Digger in front and use its engines to push). I can take some pieces breaking. especially because, unless the hitchhiker somehow works, there's no way i can avoid it.

Edited by king of nowhere
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Part 4: Dream even bigger

Brute force solves all problems. If you're failing to solve a problem with brute force, you're not using enough of it.

Here I attempt to tackle the radiation problem by adding some 1200 tons and 150 parts to a ship that was already ludicrously big to start with, besides fixing several minor inconveniences. In the end, the new, improved DREAM BIG is ready for its voyage (again)

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Spoiler

So, as I decided I'd remake the ship and fix all those small problems I found, I still was uncertain about radiations. Those are the main killer. What can I do? Swap the crew? I'm not even sure that will be enough! Make a small ship with ion engines and a crapton of xenon to reach everywhere in months? That would be much less spectacular. Trick the game? That would be cheating! Lowering the difficulty? That would also be cheating! But what can I do? The game gives me two ways to deal with radiations: shielding and active shields. I already have the most shielding I can, and it blocks 90% of radiations. As for active shields, I already have 9. Each one blocks 0.04 rad/h, a solar storm averages 5 rad/h, it would take 120 active shields to protect from that! I can't carry 120 active shields!

....

Wait, why not?

Those things would add some 350 tons of dry weight. This ship already weights 3600 tons, 1000 of dry weight. 350 wouldn't be that much. And if I worry about losing deltaV, since I'm there I may also add a couple more S4 big tanks. It would not be cheating, it would be spectacular, it would work. Let's do that.

So here's the new Home mothership

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The main change is, of course, the addition of 120 active shields and 2 big tanks. I am a bit sorry I had to block windows from the crew compartments; then again, one of the many plans real space agencies are making is to make a similar arrangment, and use the fuel as radiation shielding. Now it makes me feel extra safe. Yep, nothing like being surrounded by 3000 tons of explosive chemicals to feel safe!

But there was another problem with shielding. Even though i had maximized it everywhere, the resources tab still showed it lacking. Eventually I discovered the problem in the gravity rings; they have shielding, but it cannot be added from the VAB. I fixed that by editing the file.

Since I was there, I took the chance for other small works. I moved around the antennas in a position I liked better. I had to move around the docking ports, since they would not fit anymore in their old places. I reduced the number of radiators, as they weren't needed. I added a couple of sentinel telescopes, I will include asteroids as possible refueling destinations. I added some chemical plants to make monopropellant, now I don't have to worry about running out.

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I used the base of the big tanks to add two more engine packs. Now I have 20 wolfhounds, resulting in better redundancy and thrust. I also swapped out the two standalones to put in two rhinos: the rhinos have high thrust while still keeping a decent Isp. I lose some fuel efficiency, but I gain a lot in correction manuevers. And if I don't need high thrust, I can shut them down. I also moved the small docking ports on the bottom of the craft, they work very well and the whole ensemble is less cluttered. I fixed the RCS system, now I have 4 Vernor pointing in each direction. This makes Home surprisingly manueverable, for its size.

Finally, I moved back the rear cupola to better admire the rocket packs in action. It was a very good idea

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I didn't want to invent yet another launch vehicle by adding even more mammoths to the launcher, strapped in even more unlikely ways. I added a couple engines, but I also decided to use more the ship's own fuel. If I must refuel it with a mission, I may as well plan around it. Launch was great

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And I also confirmed that yes, that launcher still works even if one engine explodes

As for the rest of DREAM BIG...

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I fixed the drills on the Diggers. Now they are correctly for water and nitrogen (not shown in the picture, only Digger 1 and Digger 2 have those). I removed the broken stepladders. And I added a small docking port as shown in the picture (those only on Digger 3 and Digger 4). This allows me to couple with the last stage of FU Eve (I wonder if I should give it a different name after it comes back from Eve and is ready for Laythe) without having to carry an adapter to change from medium to small clamp-o-tron. I placed the docking port there because it will keep the FU Eve parallel to the Digger's body and not too far from its center of mass, as to minimize instability problems.

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I added two engines to the Dolphin escape pods, including extra solar panel to work them far from Kerbol, and I decided to use some of the huge gas tanks offered by kerbalism for the xenon, mostly to save some parts count (everything that can help my poor CPU is welcome). I also removed the radiators, they're only needed inside Moho orbit, and I'm not going there.

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I added some separators for jettisoning used parachutes. I pulled back the wings, and I added some more. Will that be enough to stabilize the rocket? But most important, why didn't I think to include the airbrakes in the jettisoned part?

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I actually tested the Tylo stage, something I didn't do the previous time. And of course, it was all faulty. Good thing I thought about it.

First, it had too little thrust. I started the braking manuever in a 45 km orbit, and I crashed on the ground. I could have probably survived starting the braking from even higher up, but why not add a couple rockets? I lose 100 m/s of deltaV for their weight, which is vastly compensated by the more efficient manuever.

So, during the last part of descent, the upper tank is removed, and the sepratrons push it away from the main ship - a lesson I sorely learned from my first Tylo landing attempt, back with the Marco Polonium, when I was destroied by my own spent fuel tank. Except, those sepratrons weren't making their job. Because, with symmetry, they were pushing in opposite directions, and thus were merely spinning the tank. It still fell back over my lander. I fixed that, now they correctly push the tank away.

Then I landed, and after bouncing a couple of times, I flipped. Or sometimes I broke something. So I realized I needed landing legs. While at it, I also realized a 4k battery for this tiny ship is way overkill, especially when I also have a fuel cell, so I used a small battery to save some weight.

Finally, just as I thought I was done, I had a sudden realization, something that already came close to costing me the mission when I was using the Flying Christmas Tree: the ladder!

I'm used to just use the jetpack to get in and out of small landers, and I never remember that on Tylo it won't lift me! I certainly dodged a bullet there; can you imagine if after a month of playing I finally reached Tylo, and there I was unable to plant a flag because I had no ladder to return to the ship? Well, in this case I'd have probably cheated some with altF12. Still, better to have the ladder.

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As for the Trucker Moho stage, I added four more engines, and I filled the xenon tanks entirely. Now with 25 km/s I really should have enough to deal even with Moho. I also added some small radiators, they weren't necessary but it just feels wrong to go so close to the sun without them.

Assembling the ship in orbit was once again made complicated by strange krakens

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The flat-earthers may try to use this to argue that planets are not spherical; they appear to be some kind of hyperboloid instead

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And here I simply forgot to autostrut one of the Diggers

And after all was done, I finally discovered that I forgot the small docking ports and had to start again.

I will be honest, I did use the cheats to speed up ship construction. I still launched the main ship, the only one who was changed enough to fly differently. The rest are 15 individual ships that must each be flown individually. And because DREAM BIG is so big, every time I come close the game stops several minutes for loading. And it lags badly. Instead I took my landers and stuck them on top of each other, so I could save on loading times. And multiple rendez-vous. And then I edited the save to refill the tanks.

It still took half a day. After I already lost a day for forgetting the docking ports. I don't feel like there's anything wrong there. That's not cheating, there was no risk and no cost in those missions. I'd never cheat to help my mission. Here I am just skipping some boring parts. The first time I did launch every single mission, and it took 2 days to assemble the ship.

EDIT: the additions bring up the cost by 7.7 millions, to 19.4 millions. High quality active shields are 56k each

Edited by king of nowhere
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Part 5: Landing on the inner Kerbol system

In the first leg of this trip, the DREAM BIG settles in orbit around Eve, while the various shuttles are sent to land on Eve, Gilly, Moho. Solar storms are no longer an issue. There were many unplanned obstacles, but everything worked out, barely.

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This bug with flags is ruining my snapshots

5.1) E unum, pluribus

Spoiler

Fuel had been an issue the previous time. Eve is deceptively easy to reach, but it always end up being more expensive than planned. Awful planet. So, this time I strive harder for a Mun gravity assist to save a bit of fuel.

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I don't know why, but to reach Duna I can go for a Mun assist and end up on a direct intercept. Eve should require less deltaV, but I still need a further manuever Eve requires a much greater plane change, that's why. Stupid planet. I hate you.

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The improved engine pack helps make more precise manuevers

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Skimming Mun surface

During the 200 days trip, the DREAM BIG got hit by no less than 15 solar storms. There was a 100 days period of quiet between days 180 and 275, but aside from that, it was almost one storm every 5 days! That's a ridiculous amount. Still, the new, improved DREAM BIG can deal with that. Those 330 tons of active shields are paying off, and in the end I still have 0% radiation exposure for my crew. Solar storms are no longer a concern. I left the notification active, though, just for the pleasure of knowing I survived unschated yet another event that should have killed me.

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A few days before reacing Eve, I split the Trucker. I realized in the previous run I've been quite stupid, entering orbit around Eve only to then get out of it, having to make a big burn in the part farthest to the planet. Awfully inefficient. This time instead I split off Trucker in advance, with a small course correction to send it on the opposite side of Eve, to get a gravity assist for Moho. It saved some 2000 m/s.

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The Trucker Moho stage

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And the Can lander

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Joining together, as seen from the rearward cupola of the DREAM BIG. I regret being unable to join them closer to the spaceship where they would be better visible; the DREAM BIG makes the game lag horribly, and this makes manuevering much harder.

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Trucker - The Can joined, all systems operational, ready to head for Moho. I decided at the last minute to include a third kerbonaut on board, the supplies allow for it

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And by just making the Trucker pass in front of Eve, I decrease periapsis by 4 million kilometers for free.

Splitting the stage earlier would have saved course correction fuel, but Trucker is vulnerable to solar storms once released

During the close Eve pass, a 1000 m/s manuever can directly send me on a Moho intercept. Intercept speed would be 6 km/s, though. I fully planned to spend that much reaching Moho, but a full 6 km/s injection burn with low thrust is awfully impractical. I'd have to start burning before I'm even inside Moho's SoI! I decide for an alternative trajectory where at periapsis I make an apoapsis-lowering burn to reach Moho. I found this a convenient way to reach planets out of optimal transfer windows, when a direct intercept would have a very low Kerbol periapsis, and intercept speed would subsequently be crazy. By lowering apoapsis at periapsis, I can get away with a higher periapsis, and the lower apoapsis results in lower intercept speed. Which is especially important in this case, because I can make a big, long burn in solar orbit, where cosine losses are not an issue.

In case this doesn't already have a name, I call it the cochlea manuever.

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Meanwhile, the DREAM BIG is entering Eve's orbit.

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Rocket braking for Eve Insertion

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A nice view of the DREAM BIG seen laterally, perhaps the only picture I have whit all landers visible. Forgetting the ship in this orientation costed me an emergency call when the batteries run out

And so I park the DREAM BIG in an elliptic orbit around Eve. No reason to circularize, it would be super expensive and it would make leaving even more expensive.

The Home mothership has always been intended to act as a fixed base while the various shuttles explore a system. It's too heavy and expensive to move freely, and 4 km/s are not so much when you can only refuel at Duna.  Once Home is in place, a Digger has a budget of 4 km/s while making only a tiny difference in Home's main tanks. And a lander attached to a Digger can further extend the authonomy.

Of course, this increased authonomy comes at the cost of life support. Home can stay in space for several years as far as supplies and radiations are concerned (I have yet to see what happens exactly when stress reaches 100%; that's something I can't do anything about EDIT: wrong, but that's caused by a glitch I will only discover in my second grand tour /EDIT). A Digger can operate autonomously for a few months, and it is exposed to radiations when outside a magnetosphere. The landers can only operate independently for a few days at most.

All this to explain that Home will stay in this highly elliptical orbit while Digger 1 will head for Gilly and FU Eve will couple with Digger 3 to land on Eve (Digger 1 and 2 have the water and nitrogen drills and more science instruments; Digger 3 and 4 have the docking ports for the FU Eve).

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The parking orbit. Don't mind the planned manuever. I was trying to see how difficult it would be to reach Duna, and if I could enter Eve with a different inclination resulting in a easier or harder transfer. The Trucker was arriving at Eve a couple hours later, its trajectory is still visible

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The Gilly transfer manuever planned for Digger 1

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Digger 1 undocks from Home

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Digger 1 is leaving for Gilly. Without the need for high thrust, I use a single engine, to reduce the chance of malfunctions.

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Digger 3 undocks from Home

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Digger 3 docks with FU Eve

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The DREAM BIG has now been split in four pieces.

On Trucker, Val, Ellonitto and Bob are starting the long trek for Moho.

On Digger 1 Giostlo, Pendatte and Giuritto are headed for Gilly.

On Digger 3 Iabretto, Sildona and Ferdozza are aerobraking to land on Eve.

Bill, Jeb and Alrodo are crewing Home.

5.2) Landing in no particular order

Gilly landing

Spoiler

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Landing on Gilly was no particular effort.

I could have taken this chance to resupply on water and nitrogen, except there were none at the landing site. I could have tried to gather some carbon dioxide by molten regolith electrolysis, but I decided against it; mostly because it would have required me to automatize the ship, and I decided it wasn't worth the hassle for a resource I will find aplenty at Duna. I have more than enough of everything to reach that far. For the same reason, I decided not to jump to another biome.

So, now Digger 1 has to spend 18 days before Gilly is again in a favorable position to get back to Home.

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I rendez-vous with Home on this unusual trajectory

This part of the mission was easy and without any excitement. Which is the most desirable outcome for any complicated operation.

Eve landing

Spoiler

 

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Detaching FU Eve from Digger 3, for the final part

I already posted a bunch of pictures for the Eve landing the previous time, for Part 3, this time I'm skipping most of the descent

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And I arrive here, floating down on parachutes. Now the original plan requires jettisoning the shields and using a rocket to slow down in the end. After being hit by my own discarded thermal shields, though, I changed the plan and decided to try something more crazy, but potentially more practical: lithobraking!

The thing is, I am floating down at 18 m/s. The first part to collide will be the shields, and I want to get rid of those anyway. With some luck, the shields will break while protecting the rest of the ship. Worth a try.

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And it actually worked! Saved some fuel and some danger of being hit by my own debris.

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By the way, reentry stress caused a lot of problems with the ship, now the rocket joints are all half broken. This won't be good for flying

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Taking the looong climb down. It's at times like this that I realize how huge is the stuff I'm building

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On the placard I wrote "bad planet!"

Now it's time to leave. According to the plan, I jettison the spent parachutes. Of course, they just stay on top of the rocket, and only come free during flight, when they can make damage. Why was I expecting any kind of different outcome?

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Flying this thing was as much an aerodinamic nightmare as the previous time; on the plus side, a little extra fuel (the previous time I split FU Eve from Home before the insertion burn, and I used the FU Eve's own engines for it) helped. But the most helpful thing was already having done this launch twenty times, so I got it right after "only" four or five failed attempts. The main problem: After splitting the boosters, at least one of them crashes onto the main ship. To prevent that, I have to stop the engines and slow down to 100 m/s, after which I can detach the first stage safely. Enough. The last stage flies smoothly, mostly because it's already out of the atmosphere. Again, I was too busy trying to steer to snap pictures. Plus, they wouldn't convey the idea

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The new attachment point, at least, works perfectly. The ship if perfectly stable even while using one wolfhound at full power.

It went better than the last time, but still the FU Eve was quite faulty and could use lots of improving. What I learned from this

- Next time I will add another staging on the "tower" holding the upper thermal shields, and I will attach the parachutes there. No more problems with their separation, no more aerodinamic issues because the ship doesn't have a nose cone

- No matter how much I am attracted to the idea of recycling stages, I will not try again to use the Laythe lander as last stage for the Eve lander. This forces a stage much heavier than it has to be, and in turn it forces a much heavier Eve lander. Not to mention the aerodinamic damage caused by the wide base necessary to land upright on Laythe. Ultimately, it would have been much cheaper and efficient to use two different spaceships. Sometimes reuse just does not work. Furthermore, every time I use FU Eve's engine for a docking manuever, I cringe in anticipation that it may explode. If it explodes, I cannot land on Laythe, and mission will be partial success at best.

- I will never again use lateral boosters as first stage on Eve. The atmosphere is too dense, it has too much tendency to slam them against the central body. Instead, I will have the first stage discard from the bottom, so it can't damage the rest of the rocket.

And that's it. Wait, only 3 major problems? They felt much more when I was trying to pilot that monstruosity

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I almost crashed FU Eve against Home on docking, due to sloppy piloting and lag. In the end I found myself in that position, and I decided to use those docking ports I left on top of the shields. They were not supposed to be there, but I forgot to delete them after changing my mind on their placement.

Moho landing

Spoiler

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Periapsis! 3.5M km from Kerbol

Trucker's flight plan required two multiple hour burns. I performed the first at periapsis, while I was playing a Civilization IV multiplayer game. The second, for injection, while having an internet chat with friends I cannot see in person because of quarantine.

A 2000 m/s injection burn with ion engines is a complex matter. I started burning one hour in advance, while I was at the edge of Moho's SoI. The burn will last longer, but slowing down will delay reaching periapsis.

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I started at 2700 m/s. Now I am at 2300, 40 minutes to periapsis

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50 minutes later, I slowed to 1500 m/s, still 16 minutes to periapsis because I slowed down

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Circularization! Close enough, at least

During the trip I got hit by three or four solar storms, which is a lesser rythm than the DREAM BIG was hit, but still, Trucker doesn't have such advanced shielding, the crew is taking damage. Luckily, it's a slow thing, I should be able to reach Duna safely. It's now time to land the Can.

This, of course, is the part where I explode.

Of course, my lander is faulty!

I didn't try a Moho landing. I looked at the data. Landing on Moho requires 870 m/s; make it 1800 for the two-way trip. Make it 2000 for a safety margin. I have 2100. I almost drained the Can's fuel tanks a bit to save weight on the transfer stage. Good thing I didn't, or I'd be now scrapping the mission and restarting from Kerbin AGAIN!

Then there was TWR. I have 1.5 on Moho, so I can land and take off safely. Yes! Of course! With a twr of 1.5 I can land safely! Slowing down from orbital speed while spending two thirds of my thrust just to counteract gravity! And I had the same problem when I tested the Tylo landing, and I added more engines there, but I totally did not make the connection for Moho! I am so stupid! All because I couldn't be bothered to add an extra spark to the lander.

 

Now it turns out I can land, barely, if I start the rocket braking at 60 km of altitude. The combination of starting high and having low thrust to counteract the gravity leads to so much inefficiency, I end up eating all my extra fuel, and then some. I land with insufficient fuel to orbit again.

I considered, for a moment, sending the Can on a suborbital flight and sending the kerbonaut to safety with a jetpack. It's feasible, and I can use a Digger to land in the future. Except, not on Tylo. Diggers lack the thrust to land on Tylo, as well as the deltaV to leave it if they can't refuel on the ground. The Tylo stage is made to couple with the Can. Losing the Can would mean getting a partial success, at best.

If I was coupled with something with high thrust, I could try to slow down the whole vehicle, then accelerate the orbiter back to orbit, and have the lander already slowed down without spending its fuel. But the ion engines don't have enough thrust for those kind of manuevers. Same goes for sending the Can suborbital and grabbing it midflight with Trucker; I did this manuever successfully in other circumstances, but it needs a good TWR on the orbiter to slow down, pick up the doomed lander, and accelerate again before crashing on the ground.

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Well, I tried the first landing with two pilots, but the new update gives me some way to reduce weight there. So I go with just one pilot. To further reduce weight, I remove the jetpack. I won't need it. I remove the repair kits. I only have to go up and down, and all systems are redundant anyway; I can survive any single malfunction. I remove all the monopropellant (by flying around in Eva to burn it). My emergency electric generator is a monopropellant fuel cell, well, I'll just hope my twin solar panels won't both stop working. Or I hope I won't have to make too many manuevers by night. From this I gain 60 m/s and 0.03 extra TWR.

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Then I study the best moment to start braking at the last possible second.

With all those efforts, I manage to land with 950 m/s left.

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The placard states "I am a dumbass, as usual"

Now, will the fuel be enough to orbit with a low thrust ship?

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By the way, 16 ant engines create a quite bizarre exhaust

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Tilting the ship as soon as possible, I reached almost orbit, with 13 m/s. I could circularize at apoapsis and with some 5 m/s to spare.

Except, my trajectory was so low, I am going to slam against some mountains. I need to spend my thrust to raise my path and clear them. And then I'm stuck suborbital

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But the difference in speed is small enough that maybe Trucker can come to the rescue despite its ion engines

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Yes! I got an intercept at a workable speed and well half an orbit before crashing on the ground again.

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Visual contact! But in darkness the ion engines are quickly draining Trucker's batteries. And it does not have a fuel cell*

* other vehicles have fuel cells to keep emergency systems by night, but not Trucker. It's supposed to never be shadowed for long. And in case the solar panels break, there's no way I can feed the ion engines with fuel cells. So, for Trucker, my emergency power source is more solar panels

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The Can coupled with Trucker! Now let's get the heck out of here!

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Batteries at 10%. Periapsis raised at safe level. Mission successful!

Ok, I admit I intentionally increased the drama here. After raising my orbit over the mountains, I still had 5 m/s left in the Can. Which would be enough to raise periapsis to around 5 km. There are some mountains higher than that on Moho, but none on my immediate path, so I'd have a few orbits to catch up and rescue the lander. Furthermore, I could have launched again and cleared those mountains a bit better. Or I could have replayed the landing and manage to not land on one of the lowest points on Moho; starting at a few km of altitude is already enough to gain me a few m/s in gravity potential. If I really needed it, I could have managed to find up to 50 more m/s. But chasing a doomed orbiter before it crashes against a mountain makes for a better story.

It reminds me of a saying, "the smart will find a way out of a situation that the wise would have never gotten into in the first place". I was definitely smarter than wiser here.

No, not really. In space, you can only improvise so far. You can't concoct a miracle solution with resources you don't have. In space, you have to bring backup and contingencies and hope, when something goes wrong, that they can cover it. I was unwise to have a low thrust, but I was definitely wise in including a generous fuel budget on both the Can and Trucker, and this saved me.

Edited by king of nowhere
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Part 6: Welcome to the hotel Duna-Ike

In this second part of the trip, Home and Trucker rejoin at Duna. The DREAM BIG is fully refueled and resupplied. So far, malfunctions are limited, but there is a promise for more to come. Kraken attacks take their toll.

Weaknesses in the original plan are discovered, and the mission plan is revised accordingly.

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On 1/11/2021 at 7:57 PM, JupiterJaeden said:

Dude, you're insane. This is insane. INSANELY AWESOME! Can't wait to see if you are able to complete it or not. 

On 1/14/2021 at 7:24 AM, xXIndestructibleEVAXx said:

can't wait to see more!

Thanks for the support guys! This update took longer because all those refueling trips were very time consuming. Don't worry, I'll see this endeavor to the end, for good or bad. If I ever stop updating, it's because I've had some kind of real life accident.

6.1) Reaching Duna

Spoiler

Having landed on all the inner bodies, it's time to go to Duna and replenish the fuel tanks, that are starting to run low. There are well-established trajectories for an interplanetary transfer, but they won't help in this case. A regular Eve-Duna transfer costs more than 3500 m/s. Make it 3200 because when you're in a high elliptic Duna orbit you can aerobrake the rest of the way. Make it 3000, because you can get some aerobraking for Duna's injection. Anyway, the DREAM BIG has 2200-2500 m/s available according to manual calculation. But that's taken into account, because it's not starting from a low circular Eve orbit, it's already in a high elliptic orbit that would take over 1000 m/s to reach. So, this would reduce my actual transfer cost to 2000 m/s, well within my fuel budget, right?

Well, not quite. Because my elliptic orbit is not quite pointing in the right direction for a Duna transfer. If I extend my elliptic orbit, I end up missing Duna by a couple million km. If I wait for a better orbital position, my elliptic orbit would then be pointing in the wrong direction. I had to get creative, and eventually I picked the trajectory shown below

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A small 300 m/s manuever to kick my apoapsis close to Duna, followed by a large 1400 m/s manuever that combines plane correction with a strong radial and prograde component. It has the big disadvantage of having a big apoapsis-raising manuever in Kerbol orbit, away from any source of Oberth effects. It has, however, several benefits:

- makes full use of my initial orbit

- confines the big burn to Kerbol orbit, where cosine losses for low TWR are not a problem and can make full use of the efficient wolfhounds, and couples it with the inclination change

- is relatively fast, at least compared to the alternatives (while I still had to wait years at Duna for the transfer window, I wasn't sure how long Trucker's life support would last)

- it will end with a relatively small intercept speed at Duna

I'm not saying it was necessarily the best trajectory, but it worked with what I had.

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Bill (slightly to the right of the cupola) is running maintenance schedule on the engine pack before the ejection burn

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The ejection burn

200 days later, it was time for the big manuever. Everything was going right, until at some point the ship suddenly lost attitude and started spinning uncontrollably. I went out of map view to find kraken bite marks

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So, let's recap this image. There is fuel in the ship, but the upper engine pack stopped working. Its fuel tank is depleted. And there is no option to transfer fuel between tanks.

Yep. Apparently, the game decided there is no fuel transfer between two sides of the ship. Two of the main tanks are isolated from the rest. No, it's not a construction mistake; those tanks are laterally fused to each other. Furthermore, I tried to check the "ignore crossfeed rules" box, but still I could not get fuel transfer. Going back through saves, I discovered this bug wasn't here for Home, but it was already going on before I launched for Eve. Not worth restarting the mission. It's not a fatal bug.

So, for now I stopped the lower engine pack too, and moved as much fuel as I could to the central tanks, to keep the center of mass symmetric. I lose more twr, but luckily I put myself in a situation where it wouldn't be needed. And I will need to resupply the different sides of the ship separately. At least the other resources are still transferred regularly.

 

Some 100 days later (the whole trip was quite unremarkable; more solar storms were powerless against the ship), the DREAM BIG reached Duna with about 1000 m/s of intercept speed (or 600, if we consider the bare minimum to enter an elliptic orbit).

I was passably confident that this would be enough for aerobraking, because the Marco Polonium did it. However, I am discounting several facts:

- by the time it reached Duna, the Marco Polonium was down to 40 tons of mass. The DREAM BIG, despite spending most of its fuel, is still close to 2000. This means 50 times more energy to dissipate.

- the Marco Polonium was mounting entirely solar panels of the SP variety, the retractable ones. I used them specifically to make the ship more resistant for aerobraking, because they have higher thermal resistance in retracted position. I would have done so for the DREAM BIG too, had it been possible; but it takes 15 SP panels to produce as much as 1 gigantor. The DREAM BIG is sporting 64 gigantors, and I am afraid even those won't be enough around Jool. The radiation shield will have to go, and some greenhouses too. To get the same out of SP panels, I'd need 960 of them. My CPU has let me know that it will kill me if I ever try it.

If I ever remake the mission in the future (it seems I am heading for a partial or mixed success, I may want to get to outstanding eventually) I am considering adding some localized thermal shields to protect the gigantors. The ship may be able to take 600 m/s on aerobraking then.  For now, multiple tests (taking on full real life day, because aerobraking with 1000 parts causes LAAAAAAG, and reloading takes several minutes) showed that I can lose 200 m/s. The remaining 400 m/s, I must shed by rockets, and I have just enough fuel.

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please spare a thought for my poor CPU that was heroically trying to calculate aerodinamic effects on this crazy ship. It was running close to 1 frame per second in some points

The manuever indicator is a way I use to measure aerobraking; I set up a 0 m/s manuever at periapsis, and it will tell me how much speed I'm losing. In the first picture it's over 200 because I also used the rockets at some point.

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the aerobraking seen from inside several crew cabins

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Getting out of atmosphere, I lost 200 m/s but I still need a little extra. Do notice how little fuel I have left; about 60 tons, good for maybe 150 m/s

But the manuever is successful, and the DREAM BIG can enter a stable orbit around Duna and deploy the Diggers.

 

Meanwhile, Trucker also set course for Duna. Thanks to the generous deltaV allotted, it wasn't a problem

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This is actually an optimized manuever. Yes, it takes 4 km/s to raise apoapsis from Moho to Duna. Plus 600 m/s of plane change and 1,5 km/s of injection burn. This is the minimum. Moho is really that hard to reach. And to get away from. I could have saved some with an Eve gravity assist, but it would have made for a longer trip, while exposed to radiations. No, thanks. I brought 20 km/s worth of xenon for a reason. I performed the 4 km/s burn in background during an online D&D session with friends.

 

Well, at least the Trucker is light, I can aerobrake well with it.

Again, no. Going retrograde, it has a tendency to flip. And flipping exposes the delicate gigantors to the full force of the atmosphere. And afterwards, a frontal cupola isn't all that strong either. Again, 200 m/s is the most aerobraking possible.

I'm not even sure why I'm taking such pains to aerobrake, when I have 7 km/s left.

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Look at the high orbital speed; this picture comes from one of the failed attempts

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In the end, some 30 days after the DREAM BIG reached Duna, Trucker rejoined it.

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The Can rejoins with the DREAM BIG (having 5 m/s left in the tanks made this a lot easier). Trucker also rejoins, but only long enough to transfer the crew and the various resources on board, especially nitrogen gas. Then I leave it parked in orbit. Trucker has exhausted its purpose, and it would just be dead weight on the way forward. It can't even use its engines anymore for lack of electricity - it's limited at 25% thrust at Duna, and it will get worse going forward. But then, this poor thing was designed to carry the kerbonauts only back to Eve, to rejoin the DREAM BIG there. And the whole trip was planned to last 200 days, but going to Duna doubled that. I'm proud of you, Trucker. You're not being discarded; you're being honorably discharged.

The kerbonauts on board have suffered about 20 to 30% radiation damage; the sun was going through a period of low activity. Strangely, they are less stressed than their coworkers on the DREAM BIG, despite having less luxuries. Seems like a malfunction with the mod [EDIT: I actually discovered many months later that the reason is the single unpressurized Mk1 crew pod on the FU Eve losing pressurization bonus for the whole ship. Actually, I'd still count it a mod malfunction].

6.2) Refueling & Repairing

Spoiler

It's time to let out the Diggers. And since this is kerbalism, it needs to be planned. It took a lot of trial and error before the mining operation could go smoothly.

First, biomes. Some people can pinpoint their landing with startling accuracy. Some people have mods to help them. I have neither. I can go through trial and error, but I'd rather have some biome that's easy to target. From an equatorial orbit, there are two of them: lowland (highlighted by the green strip in the map below), and midland sea. The random god smiled at me upon resource generation, because they are both rich in ores.

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However, none of them has water; there is only water on the poles, something I think the mod did on purpose [EDIT: after multiple missions with kerbalism, I can say that it was a coincidence. Some planets are meant to have no water, but as for the remaining ones, where water is spawned is totally random]. I also would like to get some extra nitrogen; both those biomes are poor in nitrogen, but lowlands has just above the drill treshold. Furthermore, lowlands have an average elevation of 2000-3000 meters, while the midland sea is between 500 and 1000. Less air means less aerodinamic losses on liftoff, and higher solar panel efficiency (I congratulate the mod makers for introducing this factor too). More air means easier use of parachutes, but in the end the last leg of parachute descent was not a problem, so I picked lowlands as the biome of choice.

Refueling starts with the deorbiting burn. That takes 20-40 m/s. I left a flag in the middle of the biome, a 30 km periapsis on top of it is generally good.

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Then the ship gets pointed radially. This increases drag. Without it, I wouldn't decelerate enough. By changing from radial to prograde orientation, I can control my landing spot if the original manuever wasn't accurate.

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Parachutes were set to open with minimal pressure. Using this aerodinamic braking, they can open at around 10 km altitude, at 450 m/s.

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From here, I quickly revert orientation to retrograde. The chutes will give a huge jerk upon opening at 5000 m - even though I'm only opening 2 to minimize this. If I'm still pointing radially by then, that jerk will send the ship spinning so fast, the top structure will be ripped off. The parachutes must be opened as early as possible, the ship does not slow down significantly in the remaining distance, and the denser atmosphere will make the opening even more traumatic.

If I were to go back at the drawing board, I'd add a couple of parabrakes to try and make the parachute opening softer. I was surprised by how violent it was.

In fact, my initial research suggested I needed some 400 m/s of rocket brake before I could safely open the chutes. Finding this manuever allowed more fuel transfer.

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Notice the acceleration meter, it actually goes over 15 g for about a second

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With all chutes opened, the ship floats down at around 30 m/s. At 200 meters from the ground, the central engine is used to stop. This manuever only requires 50 m/s. The whole deorbiting-landing manuever can be safely performed with 100 m/s, equivalent to 2 tons of fuel on the empty Digger.

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Finally, the Digger is landed. At first, I thought not putting landing struts (which I didn't include for 3 reasons: 200 kg of weight that could be used to lift extra fuel, 4 parts to make the game lag even more, and I already have enough stuff attached to the Digger that adding more would be awkward) was a mistake, but I discovered that what was making the ship bounce around were the engines gimbaling around. With SAS deactivated, the Digger became perfectly stable, and capable of landing even on most slopes. Only once I really had stability problems, because I landed directly on a canyon's ravine.

On the plus side, I discovered that I can use that gimbal-bouncing effect to rotate the ship on the ground, by making it jump a little and rotate a bit while it's airborne. Good, it's easier if I don't have to worry about orienting the solar panels east-west during descent.

I make a point to save the game before landing, because sometimes I fumble the retroburn.

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Well, it only happened twice in roughly 30 missions

Now the Digger must prepare for staying on Duna. By day all is fine, but by night there is no energy, and manually dealing with it all is too much of a hassle. I had to learn to use the automated function of kerbalism.

With it, I can choose some actions that will be performed in certain conditions; by day, by night, when battery is low, when battery is high. At first, I tried to set up a day/night routine, but it was failing. As you can see from the panel orientation, at noon the panels are shading each other, causing a power shortage. This will deplete the battery, kicking in the emergency low power program: shut down the drills, activate the fuel cells. Then the sun moves and the ship has electricity again, but for the program, it's always been day. And the "daylight" program activates only when the sun becomes visible after an occlusion. So, the drills are not restarted, and the Digger stops working.

So I learned to use battery low and high. At battery high, the drills are activated, and the fuel cells stopped. At battery low, it is reverted. This eventually depletes the hydrogen storage, and produces water, that is vented out.

Here I have to digress on water venting. I set up the emergency procedure to activate the fuel cells in case of power shortage, and I set the fuel cells to dump water if necessary. This is obvious; if power production stops because the water tanks are full and the fuel cell goes offline, life support goes offline and the crew is killed by heat or cold in minutes. If the fuel cell keeps working by dumping water, I just lose a small amount of water. Easy choice. Right?

Wrong! Absolutely wrong! I'm thinking like it's real life, but this is a game. So, say I told the fuel cells to dump nothing. What happens? Water tanks are full, the fuel cells stop, the crew starts freezing. At this point, the mod authomatically stops time warp and gives me a message. I can check what's wrong and fix it. And hey, once I couldn't find what was wrong and the crew died. Then I just reloaded the game, and that was it. On the other hand, if I tell the batteries to vent water, I will lose a bit of water every night. And I will never, ever get a message for it. Not until I run low on oxygen or hydrogen. At this point, I will realize that I depleted a stockpile that was meant to last for years. And the depleting started many hours of gaming ago, so I can't just revert it by reloading the game. I must lose tens of hours. Or I must suck it up and dig new water.

To stabilize hydrogen storage, I told the program to also run water electrolysis when battery high.

So, the full cycle now goes

- dusk arrives. The solar panels can't support mining anymore. Battery depletes. Eventually it reaches 20%, mining is stopped, fuel cells are activated. Water is produced.

- the fuel cells slowly recharge the battery at 80%. At this point mining is resumed, and water electrolysis started. This depletes the batteries very quickly, and has little effect on anything else. This cycle repeats a few times during the night. All considered, some 30 units of water are produced during the night.

- morning arrives. The solar panels start producing. Battery reaches 80%, water electrolysis starts. This is so expensive, even the solar panels can't cover it. The battery depletes fast, but still a bunch of hydrogen is produced in the time.

- low batteries stop water electrolysis and mining. With solar panels in full swing, batteries recharge very fast.

- batteries recharged kickstart water electrolysis again. This cycle repeats multiple times each morning, until after a few hours the hydrogen tanks are full again. This finally stops the electrolysis, the batteries stay full and fuel production goes smoothly for the rest of the day.

It takes 7-8 Duna sol (equivalent to 20-25 Kerbin days) to fill a Digger. Then it's liftoff

nHCY7fW.png

The Diggers actually fly pretty well. I was estimating 70 tons of fuel transferred for each trip based on the 1450 m/s cost of Duna ascent from the deltaV map. That map, though, is made for normal crafts, and you normally land on Duna with something small. And small crafts are much more sensitive to aerodinamics. Digger is so big, and it has decent aerodinamics (at least compared to other landers I sent to Duna, which were never optimized for the planet; look at the Marco Polonium mission linked above if you want to see the crap I've flown through this atmosphere before), that losses are small. It reaches orbit with only 1100 m/s. Out of 200 tons of fuel it carries, roughly 110 end up in Home's main tanks.

WrzNu7R.png

Once in orbit, I run maintenance. Here Ferdozza Kerman is inspecting the engines and saying they are in good shape. I always check all the engines at every orbit, and I repack the parachutes. And since I'm there, I also inspect other random pieces of hardware. If I find one of them faulty, I inspect all pieces of the same kind; for example, if I get a message that a solar panel is close to breaking, after servicing it I also inspect all other solar panels.

I originally planned to do this on the ground; but at the first landing, I had a moment of panic when I activated the jetpack and my kerbonaut didn't lift.

Yep. The last update changed whether you can use the jetpack at Duna. And I removed the ladders. And I must get out of the ship and plant a flag for the challenge.

Luckily, I discovered that if I push the jetpack to the max, and then jump, I float. Jetpack perfectly cancels gravity, and the jump is enough to reach the crew hatch. If you aim well. There is very little control in it. You can try to swerve around a bit, but most of the times I miss the target and fall on the ground. Sometimes I smash on a solar panel.

So, after planting 3 flags in specific places to act as navigational landmarks, I decided to never go EVA on Duna again. If I remake this mission, I will install ladders, and part count be damned.  For now, all the maintenance is done in space.

Malfunctions were my main worry. I needed around 30 missions, and each one carried a small, but unavoidable, chance of critical failure. Would I even be able to complete the task? In the first attempt, just landing all 4 Diggers on Gilly causes one of them to break an engine irreversibly.

Well, in all those refueling missions, I only had a single malfunction, during liftoff, and it was fixable.

cwnAHxT.png

Now, I would like to say that I turned on the engines gradually, and at first sign of problem I shut them down and fixed them. Indeed, that's what I was doing at first. But with time, I stopped worrying. I run a lot of flights without malfunctions. So much, in fact, that at some point I even wondered if the mod was malfunctioning and engines breaking was disabled (I repetedly turned on and off an engine pack until it broke just to confirm the settings were ok). So, when the malfunction hit, I wasn't ready for it, I panicked, and I crashed.

Not wanting to cheat, but also not wanting to lose crew for a piloting mistake, I decided to reload the game, but keep reloading until I would get some malfunctions. I didn't have to worry, actually, I got the very same malfunction at the first try. It seems the mod keeps a list of malfunctions happening in the near future. Good. If I don't panic, I can totally deal with that. I stop the engines, send down the engineer, and fix the engine. Then I lift off again.

zSDilPd.png+

Oh, wait, repairing an engine shuts it down. Sigh. Reload again...

From then on, I've always been ready to shut down everything at the first alarm, and obviously it never happened again.

Only one malfunction on all those missions, have I been lucky? Well, I made some calculations, and the answer is "not too much". A high quality engine has a 0.2% chance of malfunction, so it will break 1 time in 500 ignitions. I have 5, and I use them twice for launch; one for liftoff, and one at apoapsis to circularize. I learned to avoid the repeated on-off I was using before kerbalism. After that, I shut down four engines, and only use one to perform all the small manuevers. I always use it once for the course correction to go in rendez-vous, and once to slow down before docking, and once for deorbiting and once for landing, and a few more random times for small corrections during docking. Let's say, to get a nice round number, that every refueling mission has 20 engine ignitions. And at 110 tons per mission, it takes some 30 missions to fill the 3000-tons tanks on the DREAM BIG. We're looking at 600 engine ignitions. So, 1 malfunction is actually average. Add some more ignitions for all the Eve part of the mission, I've been moderately lucky, but nothing exceptional. Also, all that maintenance I run certainly helped. It was the previous time that I was exceptionally unlucky.

A Digger can orbit with 3 engines. It can even dump some fuel and only orbit with 2 in an emergency. And while it has 2 engines, it can still act as a shuttle and ferry around the Can. But I'm glad it didn't have to. The Digger is quite a nice machine, sturdy, reliable, adaptable. I'm proud of those machines.

Once I dock the DREAM BIG, I transfer all fuel minus the one in the smaller tank on top; conveniently, what's left is almost exactly 100 m/s. I also trasfer the remaining ore, that will get converted to fuel by the Digger 3, still docked (3 Diggers used in parallel were more than enough). I transfer carbon dioxide, whose supply was replenished early. I transfer the waste, that would get processed by life support on Home (for extra redundancy on the critical processes, I preferred to not include a water purifier on the Diggers. But I saw fit to include a waste container. I can get precious carbon and nitrogen out of those, no point dumping them needlessly). If needed, I would tip the food and water supply (but not too much, the fuel cells need some empty tank space). Then it's undock and deorbit.

AcUX3D6.png

The whole cycle of landing, refueling, taking off, docking the DREAM BIG, transferring, landing again, would take maybe 1 hour of real life time. Maybe more.

I'm surprised it was so long, but you have to remember that the DREAM BIG causes horrible lag, so docking with it is always very slow. And then the whole game gets heavy, and changing any craft will cause lag. And then I am limited to time warp x1000 because the converters malfunction with kerbalism otherwise. And while I am waiting, I start doing something else and then I want to finish... Yep. It was a long, long process. I don't want to have to do it again.

Refueling in other resources

That's for fuel, but a long term spaceship also needs oxygen, hydrogen, carbon, and nitrogen.

For hydrogen, I needed water. Only the poles had some, and orbital inclination was too much of a hassle. But I launched the two Wings, and I found more water on Ike, easier to gather. I'm planning to go there anyway.

ZNcSiRV.png

Wings 2 over the Duna's north pole

mG8jWXn.png

Wings 1 exiting the shade of Ike.

I'm not planning to recover the Wings. No use for them where I go, their solar panels are inadequate already, their fuel mass ratio is no better than the rest of the ship, and they add parts count.

Carbon was easy, I included the atmospheric harvesters in every Digger, and they worked faster than anticipated (because the nominal value is for 10% CO2, Duna's atmosphere is like 95% CO2). Carbon dioxide was replenished in days.

Oxygen required running some molten regolyth electrolysis on some of the mined ore, it wasn't a problem.

Nitrogen proved impossible to get in significant amounts.

Yep. I should have read the fine print. Kerbalism has a weird approach to resource counting.

The thing is, Digger 1 and 2 carried both a small water drill and a small nitrogen drill. A small water drill extracts 0.18 water per minute. But that's actually a lot of water. A kerbal drinks 0.13 water per day. From one unit of water, you get 1250 units of hydrogen, half as much of oxygen (and kerbals need 37 oxygen per day)

A nitrogen drill extracts 0.15 nitrogen per minute. At 10% abundance. Top abundance on Duna was 2.5%. On Ike, there was no nitrogen whatsoever (it's true, unfortunately; nitrogen is fairly rare in rocky planet crusts). And 0.15 nitrogen is a pittance. It takes 2700 units of nitrogen to make a single unit of monopropellant. I can't find solid figures for how much it takes to run the greenhouses, but 0.15 per minute isn't even enough to compensate for hull losses on the DREAM BIG. So, while I collected as much as I could (the nitrogen drill was the only part instructed to run all the time, even by night), it was negligible.

I should have enough nitrogen for over a decade, which should allow me to finish the tour. And suddenly I'm very glad I have the dolphins to GTFO if I run low faster than anticipated.

But having limited nitrogen suddenly turns the mission in  a race against the clock. I can't dally around Duna forever, going back from Jool, waiting an Eeloo transfer. I have to hurry up.

On the plus side, while kerbalism should consume monopropellant for EVA jetpack, it's not doing it. Seems, again, a malfunction introduced with the latest KSP update. Well, for once a malfunction working in my favor.

General maintenance

Speaking of maintenance, shortly after reaching Duna I also run a full checkup on the ship systems, including every single solar panels on board. They are the only part not of high quality (because most high quality parts only weight 10% more than normal; high quality solar panels are 50% heavier), and they are feeling their age. It's already been over a year, and some of them are about to break. I will run a similar full checkup roughly every year. I run a second one 50 days before the first launch window, and most of them needed servicing. None broke, though, while I lost one on both a Wing and Trucker, now that they are unmanned and not subject to maintenance. It feels good that the effort to keep the DREAM BIG in healty condition is paying off.

Wpy9lbs.png

Bill starts the inspection round from the engines. Stops at a random reaction wheel

3FarBtX.png

Here Bill is inspecting the radiation shields. After a couple dozens are all in good conditions, I decide there's no need to check the rest. They are high quality, and exceptionally durable

u31149v.png

kIlj3xD.png

zaomSFq.png

Working on the solar panels. All 64 of them, one by one

:rolleyes:Hey, at least you only have to click on the mouse three times. I am the one manually inspecting all those things, while stuck in a space suit.

Riiight. Sorry Bill. I won't complain anymore.

6.3) Ike

Spoiler

At times it seemed like refueling would never end, but eventually, the deep tanks of the DREAM BIG were sated. So I sent it to Ike.

Why Ike? Well, first, I needed water. Ok, I could have sent a lone Digger for it. Much cheaper.

But then, interplanetary transfers are also cheaper from Ike. From a high Ike orbit I can fall towards Duna for only 50 m/s, and then I am again in Duna's orbit, but with 300 m/s of prograde speed.

lQGQxUf.png

I spent over 300 tons of fuel for this, which I had to recover with more Digger trips to Duna :/

XkMqmkv.png

Digger 2 lands on Ike. I only loaded 30 tons of fuel on board, for greater savings.

7r7I21U.png

Digger 1 is rendez-vous with Home after another refueling trip. It can bring some 80 tons of fuel from Duna to Ike. That trajectory is surprisingly cheap

I sent Digger 1 with a crew only to plant a flag. At the first solar storm, I sent it up to the protection of 120 active shields, and then down again uncrewed. Kerbalism gives no engineer boosts to mining production, and Ike has no magnetosphere, so no reason to expose a crew more than needed. Well, they could fix malfunctions, but even two broken engines wouldn't stop a Digger from leaving Ike and reuniting with Home.

Speaking of storms, around this time I learned that there was a whole kerbalism manual on the internet and that I missed several pages of it. What I thought was the full thing was actually only the introduction.

All this was caused by my irrational dislike of github. Really, I can't get the hang of it. I can navigate any other site, but I get a link to github, I get lost.

Anyway, I discovered that heavy parts actually protect against radiations. You are supposed to survive solar storms by putting some large fuel tank between the sun and your crew cabins.

I wonder what would have happened if I had discovered that before adding 120 active shields.

5vyMEUf.png

Then again, I probably would have anyway. A storm still damages all your other hardware. The shields keep my ship in good conditions.

But at least this means I have a better chance of surviving without those shields. I checked, and even with tanks half empty, the Diggers can protect their crew completely if they are angled correctly. Suddenly, I can send a Digger on its own for a couple of years. Suddenly, recovering a Dolphin without the crew getting killed during the trip seem possible. I realize that's why Trucker had less damage to the crew, by the way, it was oriented in a way that shielded better.

This opens up new possibilities. But I will discuss them in the updated mission plan.

Anyway, it was now the beginning of year 4. My next target is Jool, for the simple reason that after I complete Jool, if I can't go on I can launch the Dolphins, and still claim partial success for having almost made a grand tour, skipping Eeloo and Dres. If I skip 5 landings from the Jool system, I can at most claim mixed failure. The launch window is at year 5, day 200 (even the windows for Eeloo and Dres are close, by the way). So, I have to wait one year around Ike.

During this time, I had the first stress breakdown

uF7Umuf.png

This hit was close! Luckily the damage could be repaired, but the Tylo stage is one of the least replaceable parts. It can still land without one engine - I made sure of it - but it's the difference between a safe comfortable landing - as comfortable as a Tylo landing can be - and a grueling ordeal like I had at Moho. The only worst part to damage would be the single FU Eve engine, that would prevent me from landing at Laythe entirely.

More breakdowns are arriving

UFZAkKu.png

And by the way, I also lost a solar panel on Trucker. It's unmanned, it hasn't undergone maintenance. It shows all my Bill's hard work with the panels is paying off.

After a breakdown, stress is reduced by 50% and it starts rising again. I'm looking at one similar episode per year, per astronaut. Not good.

And by the way, having MORE astronauts is INCREASING danger? It should be the opposite. I will suggest something to the modders.

One of those breakdowns end up doing the first permanent damage to the DREAM BIG

bMcHkm1.png

It's a cupola's reaction wheel. Good. I have several dozens reaction wheels on the DREAM BIG. If I had to make a list of parts I could live without, that cupola would have been close to the top. Redundancy is starting to pay off.

KOoJbXY.png

Here Giuritto is repairing another reaction wheel broken during a breakdown

One breakdown caused me to lose ammonia, but the amount was negligible. I was much hoping it was a fixed amount instead of a % of the whole stock, because in the latter case I would be screwed. In the first case, it's a mosquito bite to the DREAM BIG deep tanks.

All in all, this year served as a proof of concept for the longer Jool trip, and I am confident that the DREAM BIG can make it with limited damage. Though it can't stay in space forever at this rythm of malfunctions, it can tank a lot of damage.

Radiations were a greater problems; despite the shields, the crew accumulated some 5% damage. I think it's caused by the time warp. I don't have enough battery to keep the shield active when in shade, though being in shade also protects me from storms. So I programmed the shields to shut down in shade and restart if irradiated. But probably time warp is causing problems here. Anyway, during the trip to Jool I'll be in sunlight constantly. If I had taken more damage, I'd reload.

[Cue in a couple months, with the mission almost done, when the crew will have left a dieing DREAM BIG to escape with Dolphins, and that 5% will be the difference between life and death... NOOOOOOOOOOOOO!!!!!!!!!!!!]

Also, the science lab is supposed to have a radiation decontamination unit, but I haven't seen it do anything.

I am now 50 days before the first launch window... To Dres. Yes, to Dres. I changed some plans.

6.4) Updated mission plan

Spoiler

Why the hell I'm going to Dres? Well, I'm not. Not with the whole DREAM BIG. But let's start from the beginning.

The nitrogen scarcity, the repeated breakdowns, the solar panels getting increasingly roughed up, all those things are pointing at a single conclusion: time is precious. Furthermore, I checked the transfer times and costs, and the original hope of finding a reasonably priced Jool transfer for one year travel time was foolish. I don't have the time to stick to the original Jool-Duna-Dres-Duna plan. Also, I haven't visited Mun and Minmus yet, a dire mistake; I was afraid of consuming fuel I'd need at Eve, but I now know I could have spent 50 tons with a Digger and the Can. Look, 50 tons are exactly what I had left, so perhaps the whole "must not spend anything" wasn't such a stupid idea... anyway, the DREAM BIG must return to Kerbin with enough working pieces that it can send something there.

Meanwhile, I also gave a better look at the orbital transfers, and I discovered that I can't send the DREAM BIG to Eeloo. Just too much fuel needed. But at the same time, I discovered that I can send a Digger around, provided it is stocked with food... which the Dolphins have aplenty.

Here is a table of transfer times and costs

NxkCDrS.png

 

So here is the updated plan. DREAM BIG will go to Jool. Starting from Ike it should take perhaps 1200 m/s. At Jool it will enter Pol orbit. Not sure how much that will cost. Surely some hundreds of m/s, hopefully not much more than 500 m/s. Let's say 800 m/s to keep a round 2 km/s so far. I will arrive at the end of year 7. There I have 200 days to explore the system, more than enough. But at year 8 there is also the rare Jool-Eeloo transfer window; I learned of it traveling with the Marco Polonium. It's only 900 m/s starting from Pol. I can't send the DREAM BIG, but I can send a fully supplied Digger coupled with a Dolphin. The Digger reaches Eeloo in 3 years (it can go a bit faster at the cost of more fuel) and land. Then the crew jumps aboard a Dolphin and get back to Kerbin in one year (with 15 km/s it should be possible). the Digger, in automated mode, will try to limp back to Duna in its own time. Just for the sake of recovery. I doubt it will make it.

Meanwhile, the DREAM BIG, after 200 days at Jool, will return back to Duna. It will take 2300 m/s for that trip, but the planner considers a nice circular low orbit; I can aerobrake 200 m/s at Duna to end up in an elliptic orbit, and from there I can aerobrake 350 m/s more for the circular orbit. Overall, it's 550 m/s saved, so I can actually do the return trip with 1850 m/s. Total cost, 3850 m/s. Add in some fuel I will have to spend to send the Diggers and the Can around Jool, which is still fairly small compared to the DREAM BIG fuel budget, I should barely make it. Then I refuel at Duna with the two or three Diggers I have left, I return to Kerbin, and explore Mun and Minmus. If Home cannot return, I will use the Dolphins to evacuate the crew, planting flags at Jool and returning the crew alive is worth a partial success even if I lose Home - or a mixed success if I also skip Mun and Minmus. I will try to save a Digger with the Can, so I can still land on Mun and Minmus. Maybe. Maybe I can send a Dolphin at Minmus and land a kerbonaut with the jetpack. Making a grand tour and skipping only Mun would definitely be worth a "making an ass of myself" mention to go together with the partial success, though.

Yes, but Dres? Ye fools, Dres is a lie! Since the DREAM BIG cannot go to Dres, I will send a Digger and Dolphin there. They will leave Duna slightly before the Jool transfer, and it will take 1700 m/s. Again, a bit less because I launch from Ike. Then I will land Digger, it will take 900 m/s going up and down. At this point Digger will have 1500 m/s left, a bit less since it carries also a Dolphin. Anyway, it could go back to Duna, barely, on its own, or it could rejoin with the DREAM BIG at Jool. Well, not the second option, because the Dres-Jool window is at year 15. The crew won't live that long. So, if I send the Digger back to Duna (where it lands and wait for Home to get back. Maybe it can save it by providing just enough extra fuel to finish the orbital insertion. Or maybe it will break down in the harsh space environment), the crew will have to go on. I can send it immediately to Jool, it would take 3000 m/s (a pittance for a Dolphin) and 2 years starting immediately. Or I could send them back to Kerbin. The second would make more sense anyway. However, if I launch a massive ship from Kerbin, and then it split and every part goes a separate way, that's not a grand tour, that's a bunch of separate missions that just happened to start together. It was ok with Trucker because it rejoined Home. It will be ok with going to Dres, if I rejoin the crew at Jool. If I don't... well, it's still mission accomplished. But it's a lesser achievement. I will decide on which to try depending on radiation damage and Dolphin conditions.

I almost certainly will lose a Digger or two, and Trucker won't survive space for another decade, I will retire it. So, it seems "outstanding success" is outside of my grasp, even in the most optimistic chance. "Complete success", where I still plant a flag everywhere and bring the crew home, is still on the table. "Partial success", where I skip one or two worlds, is also a distinct possibility. Radiation damage will be a wild card. I know I can survive solar storms (and by the way, the mod is set for 2 hours average duration. And it was so in the beginning. But now every single solar storm is lasting 6 or 7 hours. Something else is glitching. Longer storms, radiation decontamination not working, faster stress... now you see why I'm not ashamed of using the eva propellant glitch to my advantage?), but for how long? And how long before the ships start accumulating irreversible damage? They all can lose one or two pieces and survive, but how about 3? 4? It may well be that a couple kerbonauts will die of radiation poisoning. Or a Dolphin will lose all its solar panels and lose itself, adrift in space. Those events would kick me in the "mixed success" or "mixed failure" at best.

The odds are still open.

Edited by king of nowhere
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Hey, I have a few mod recommendations that might make your life a bit easier. 

Time control OR persistent thrust: To make those long burns easier.  With time control, you can also slow down time which puts less stress on the physics engine for when you are handling tons of parts and what not. In-game time goes slower but your computer will run a lot better. Time control actually has a bunch of features that allow you to basically take complete control of time in the game, but you don't have to touch most of them. I haven't actually used persistent thrust but I've heard it can help with the long burns as well. Instead of allowing faster physics warp like time control does, I think it just allows you to calculate "thrust" in an abstract way using normal time warp (i.e. instead of actually doing the physics simulation, just gradually change the orbit over the course of normal time warp while calculating consumed fuel and whatnot). 

TAC fuel balancer: This mod makes resource transfer so much easier. You can basically use it to transfer any resource between any compatible tanks on the same vessel, and to balance a resource between several tanks as well. Kerbalism actually uses a few pseudo-resources that do show up in the TAC FB menu so just make sure not to touch these. It also allows you to transfer Lf+Ox together in the correct ratio. Whenever stock resource transfer functionality breaks, I turn to TAC FB because it works way better and is way more customizable. 

kOS: I have no idea if you are into programming at all but if you want to be able to better automate tedious things you can try this mod. kOS does actually add a few parts that you need to use it though, but I think there is another mod that will add kOS functionality to all stock probe cores and command pods so you don't need the new parts. 

Some part welding mod: Since I have never tried anything requiring an absurd number of parts, I've never actually needed to use one of these. But I've heard part welding mods can work wonders when you are dealing with large numbers of the same part. For example, you could probably combine each column of greenhouses into one part. I have no idea if this plays well with Kerbalism or not, but it seems like it could help with the large part count issues. I don't know of any mod that allows you to weld together parts on an existing vessel, so this would require you to restart the mission, so I only recommend it if you choose to do that. 

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1 hour ago, JupiterJaeden said:

Hey, I have a few mod recommendations that might make your life a bit easier. 

Time control OR persistent thrust: To make those long burns easier.  With time control, you can also slow down time which puts less stress on the physics engine for when you are handling tons of parts and what not. In-game time goes slower but your computer will run a lot better. Time control actually has a bunch of features that allow you to basically take complete control of time in the game, but you don't have to touch most of them. I haven't actually used persistent thrust but I've heard it can help with the long burns as well. Instead of allowing faster physics warp like time control does, I think it just allows you to calculate "thrust" in an abstract way using normal time warp (i.e. instead of actually doing the physics simulation, just gradually change the orbit over the course of normal time warp while calculating consumed fuel and whatnot). 

TAC fuel balancer: This mod makes resource transfer so much easier. You can basically use it to transfer any resource between any compatible tanks on the same vessel, and to balance a resource between several tanks as well. Kerbalism actually uses a few pseudo-resources that do show up in the TAC FB menu so just make sure not to touch these. It also allows you to transfer Lf+Ox together in the correct ratio. Whenever stock resource transfer functionality breaks, I turn to TAC FB because it works way better and is way more customizable. 

kOS: I have no idea if you are into programming at all but if you want to be able to better automate tedious things you can try this mod. kOS does actually add a few parts that you need to use it though, but I think there is another mod that will add kOS functionality to all stock probe cores and command pods so you don't need the new parts. 

Some part welding mod: Since I have never tried anything requiring an absurd number of parts, I've never actually needed to use one of these. But I've heard part welding mods can work wonders when you are dealing with large numbers of the same part. For example, you could probably combine each column of greenhouses into one part. I have no idea if this plays well with Kerbalism or not, but it seems like it could help with the large part count issues. I don't know of any mod that allows you to weld together parts on an existing vessel, so this would require you to restart the mission, so I only recommend it if you choose to do that. 

time control or persistent thrust: can you provide some links? (bolded to attract attention)

i was about to ask for some mode like that in the future anyway, since at some point i will have to send a dolphin back from eeloo. And ion engines powered by solar panels at eeloo, for a 10 km/s burn... yep, i'd rather not do it normally.

as for time control, my poor pc already goes at 1/3 regular time when controlling the main ship. really, i checked the in-game timer with an external chronometer, 31 real seconds to 10 game seconds.

Kos: i only have the faintest training about programming. stuff like editing a saved game file is the apex of my skill.

part welding: no thanks. I don't know how many krakens it would attract, but i'd rather not find out. and there's still plenty of parts i wouldn't be able to join, like the over 100 solar panels, the approximately 80 engines, the 50odd rcs... joining a handful of greenhouses and some fuel tanks is not worth the risk.

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3 minutes ago, king of nowhere said:

time control or persistent thrust: can you provide some links? (bolded to attract attention)

i was about to ask for some mode like that in the future anyway, since at some point i will have to send a dolphin back from eeloo. And ion engines powered by solar panels at eeloo, for a 10 km/s burn... yep, i'd rather not do it normally.

as for time control, my poor pc already goes at 1/3 regular time when controlling the main ship. really, i checked the in-game timer with an external chronometer, 31 real seconds to 10 game seconds.

Kos: i only have the faintest training about programming. stuff like editing a saved game file is the apex of my skill.

part welding: no thanks. I don't know how many krakens it would attract, but i'd rather not find out. and there's still plenty of parts i wouldn't be able to join, like the over 100 solar panels, the approximately 80 engines, the 50odd rcs... joining a handful of greenhouses and some fuel tanks is not worth the risk.

All of these mods are at least listed on CKAN, but a couple of them don't support automatic install (you can still install them through CKAN they just won't update automatically I think). 
But if you don't use CKAN (why?) here are some direct links: 

Time control: 

Persistent thrust: 

TAC fuel balancer:

 

Also, the thing about time control is that when you use the slow-motion mode it reduces the rate at which the physics engine is trying to calculate physics frames, which can help performance. You can also try adjusting the physics delta-time (time control lets you do this with a convenient in-game GUI but you can also do it through the stock game settings in the main menu). The higher the physics delta-time, the more the game prioritizes physics frames over drawing game frames (so the physics engine will run faster but your FPS will suffer). Lowering the physics delta-time has the reverse effect (slower physics engine, higher FPS). 

You could probably also use time control and persistent thrust together, but I have NOT tested this. Even if it doesn't work, there shouldn't be any game-breaking consequences as long as you quicksave before testing it.

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Just a short notice; i discovered that there is a bug with radiations at high time warp that makes shielding ineffective. now i am limited to x1000 during storms. And i am in a time of high solar activity, i spend more time in a storm than out.

this, and other problems related to radiations, are slowing me down greatly. the duna-dres 600 day transfer would take a few minutes at high time warp in stock game, but i've been at it several days and i'm still 300 days away.

and i don't dare try any of the time-speeding mods because they may trigger the warp bug. and last i checked, they weren't even updated for the last version.

it may take me a while for another update.

 

 

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21 hours ago, king of nowhere said:

Just a short notice; i discovered that there is a bug with radiations at high time warp that makes shielding ineffective. now i am limited to x1000 during storms. And i am in a time of high solar activity, i spend more time in a storm than out.

this, and other problems related to radiations, are slowing me down greatly. the duna-dres 600 day transfer would take a few minutes at high time warp in stock game, but i've been at it several days and i'm still 300 days away.

and i don't dare try any of the time-speeding mods because they may trigger the warp bug. and last i checked, they weren't even updated for the last version.

it may take me a while for another update.

 

 

I think I remember seeing something about the x1000 limit being due to a mod conflict? There was something about it on the Kerbalism wiki, you should check it out. I think it was on the section that had to do with resource processing but I don't remember exactly.

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4 minutes ago, JupiterJaeden said:

I think I remember seeing something about the x1000 limit being due to a mod conflict? There was something about it on the Kerbalism wiki, you should check it out. I think it was on the section that had to do with resource processing but I don't remember exactly.

yes, it was on resource processing, but it also applies to radiation damage. i tried making the trip with high time warp and died in 200 days. i made it again at x1000, and i didn't get a single point of radiation damage.

this warp bug is also the reason my crew in Home took some 10% damage during the year spent at Duna.

i have no other mods besides alarm clock and wind gallery, i doubt there is any mod conflict

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On 1/24/2021 at 4:28 PM, king of nowhere said:

yes, it was on resource processing, but it also applies to radiation damage. i tried making the trip with high time warp and died in 200 days. i made it again at x1000, and i didn't get a single point of radiation damage.

this warp bug is also the reason my crew in Home took some 10% damage during the year spent at Duna.

i have no other mods besides alarm clock and wind gallery, i doubt there is any mod conflict

Well that sucks, you could maybe try posting about it on the Kerbalism thread? Or opening an issue on Github? It's possible someone has had the same issue before and it might be fixable. 

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1 hour ago, JupiterJaeden said:

Well that sucks, you could maybe try posting about it on the Kerbalism thread? Or opening an issue on Github? It's possible someone has had the same issue before and it might be fixable. 

i opened a bug report on github. i was told that the time warp bug is well known, but they can't fix it. nothing to be done, at least in the short term.

 

at least the sun went out of its period of high activity, so i have to stop for storms a bit less often. i will be ready for a new update soon

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Part 7: It's a long way to Dres and Jool

(it's a long way to go)

(and radiations)

Digger 1/Dolphin 2 is launched towards Dres. The rest of the DREAM BIG goes on to Jool. Trucker is sent back to Kerbin and recovered. This part ends with the Dres landing. In stock game, the 2-years trip would take a few minutes with time warping. More problems with radiation management, and some bugs related to radiations and time warping, turn this a long, hard task with kerbalism, requiring innovative solutions.

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This is clearly a faked Dres landing, staged on Mun. Can't you see it looks identical? Checkmate!

7.1) Digger 1 leaves Duna

Spoiler

Duna was my crew's home for almost two years, but eventually the planets aligned properly and it was time to leave. First, at 5:130, was Digger 1 with Dolphin 2, heading for Dres. I was a bit nervous about it all. I had discovered that the body of the vehicle could effectively shield the crew from radiation, but I never tried it on long trips. It would take 2 years to reach Dres, and the better part of another year to return. Furthermore, the solar cycle is at maximum activity, so there are lots of storms. Who knows what would happen?

On the plus side, it means solar activity will be at a minimum during the longer and more dangerous trip to Eeloo.

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Accurate and absolutely-not-cartoonized depiction of an angry sun at solar maximum. 92% isn't particularly meaningful, as the percentage fluctuates randomly around an interval, making it impossible to judge if it is increasing or decreasing. Notice the storm duration; it is set for an average of 2 hours

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Docking the Dolphin and Digger together

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A survey of the various supplies. Water seems to be the limiting factor, but I carry enough hydrogen and oxygen to make a lot more. Food sets the maximum duration of the mission

This mission was never planned for. Diggers were never intended for interplanetary travel alone (and they have limited food supplies), and Dolphins were never intended for anything but getting back to Kerbin fast. It is the hallmark of any kerbalized mission to start with a plan, realize that the plan is unfeasible halfway along the mission, and rethink everything to carry on a new plan. I am really glad I thought to include extra provisions on the Dolphins. This mission would have failed without that foresight (less foresight, and more that the 2.5 m food container was the right size, and not very heavy, and it had food for 3 years. If the 2.5 m container only had food for 600 days, I would have included one anyway. I may have managed by sending two Dolphins to Dres, though).

By the way, after a lot of hassle in my previous big mission with the Flying Christmas Tree, I learned to set up consistent action commands that would not conflict with the rovers. I learned that after realizing, in that old mission, that shutting down engines on a rover would also cause some accidental other thing while it was docked with the mothership, because I used the same number to do something else on another docked spaceplane. This time I made sure to reserve numbers. Being able to open/close all my solar panels without conflicting commands was a real time saver on those manuevers.

The whole transfer took around 1800 m/s.

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Routine fall-down-from-moon-to-get-Oberth-effect manuever. I don't know if it has an official name

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Those manuevers tend to be difficult to align, because the position of your periapsis is variable. You have to plan a periapsis manuever, without being certain of whether you got the right place for the periapsis. To obviate this difficulty, I reactivated Trucker and used it to simulate the manuever. This let me know where the best place for a periapsis is, and copy it with Digger 1

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I also finally learned how to get to Dres with limited plane correction burn. Not a burn at a node to align the orbital planes, but a burn away from a node to push the node towards the planet. It's much cheaper to fix inclination while orbiting afterwards. For the first time I was able to make a Dres transfer with a deltaV budget consistent with the minimum calculated by the alexmoon planner. I don't know why it took me so long to figure it, I've been doing the same thing going to Minmus since my first mission there

7.2) Digger 1 against radiations

Spoiler

I was moderately optimistic about radiations because, even during a storm, when the ship was correctly oriented the sensors would say "radiation level: nominal". I kept track of radiation damage through the storms. I used the same crew I sent to Moho (Bob, Val, Elionitto) because they were already exposed to radiations on Trucker. Better to send them back earlier. Then again, one may question the wisdom of sending a radiation-damaged crew out for three years during the solar maximum. It was a bit of a hazard, really, all hinging on whether they would survive the trip to Dres.

So, as you can see, at 5:134 Bob had 34% radiation damage, accumulated earlier. At 5:164, 30 days later, it increased to 35%. 1% every 30 days, it means I have 3000 days before I die (make it 1800, being already damaged). The mission should last 1200 days, I should make it with a reasonable safety margin.

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Also, do notice all the breakdown damage I'm taking. Ouch

Then radiation damage escalated until my crew died at 5:350, only 200 days later.

On a planned trip of 1200 days.

Crap.

But how is that even possible? My first trip to Eve (the one I eventually rebooted to add 120 active shields) took 200 days, and the crew was exposed to storms with the crew cabins looking directly towards the sun. I got the radiation damage simbol flashing at every storm, and yet radiation damage was only at 20%. Now I never see a radiation symbol, yet in 200 days I die? I smell a bug.

True enough, I made some experiments, and eventually concluded that time warping was causing it. Up to x1000 is fine, but accelerating time at x100000 would cycle the game too fast, and it could not calculate radiation damage correctly. After reloading the game, I was careful to never time warp x1000 during a storm (which was most of the time. Most often, a full day would not pass after the end of a storm before a new storm arrived. The only reason I wasn't hit by multiple storms every day is that a single storm would last over a day, and a new storm could not hit the same ship until the old one abated), and after 200 days there was no damage. I reached Dres 800 days later with only 1% extra damage, and I'm pretty sure it was caused by a couple of times I accidentally hit the time warp one time too many.

Since then, Digger 1 could travel in the background. I only took control a few times during the two years; for the course correction manuever, for periodic maintenance, and to produce more water at some point.

7.3) DREAM BIG leaves Duna

Spoiler

At 5:250 it was time for the DREAM BIG to leave too. Again, I took advantage of Trucker to plan the better manuever.

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The optimal trajectory would take 3 years, but it was possible to make it shorter for a small cost. Here the time table is dictated by the long term flight plan. The Jool-Duna transfer window lasts from the beginning of year 8 until 8:200, so I need to be done at Jool before then if I don't want to be stuck there with 9 angry kerbals smashing stuff at random for many more years. The Jool-Eeloo window is also in the same time frame. So, a good time to reach Jool is the beginning of year 8, leaving enough time to get the right gravity assists for Pol, and with some 150 days to comfortably explore the system. At the same time, there's no special reason to reach Jool any faster than that, as I'd still need to wait to move on. This manuever reaches Jool around 8:030 at the cost of 100 m/s over the optimal. All things considered I can't complain, I've been quite lucky with orbital mechanics. I could have had to wait at Jool several years.

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Obligatory rocket burn pics

7.4) Trucker homecoming

Spoiler

At this point I really had no use for Trucker. And without a crew to maintain it, it was starting to deteriorate, losing one of the two gigantor panels. I had no further use for it (it would have been nice to refurbish it for the Eeloo transfer, but it doesn't have any part big enough to shield the crew from radiations, and it doesn't have enough solar power to go past Duna; remember, it was never intended to go past Eve in the first place), and no incentive for recovery. But it felt really sad to just abandon it there, forgotten in Duna's orbit. Discarded for staging during a difficult planetary ascent is one thing, depowered after the end of its operational life is also a good death, but not total neglect. So I decided to recover it.

With only a single gigantor panel, Trucker was really slow. I could only work the ion engines at a small fraction of their already meager capacity. It took one afternoon to leave Duna, with two gravity assists from Ike. That was before I asked for a mod to speed up time

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The poor shuttle limping back with limited power. On the right you can also see the first real casualty of space weather: Wings 1 lost functionality for good after both its solar panels malfunctioned after only one year of independent operation. Note to self: 4 redundant high-quality engines are pointless if they are coupled with only 2 low quality solar panels. If I make the wings again, I need more solar power. RIP little probe

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This screen shows the paths of the three different ships; Trucker heading back to Kerbin, DREAM BIG having just left for Jool, Digger 1 going to Dres

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Halfway to Kerbin, Trucker lost the second gigantor. It's now stuck to emergency power. Which is just enough, after I shut down the active shield, to use 2 engines at 5% power. At least I don't have any major manuever planned. Even the 100 m/s Kerbin injection took excruciatingnly long. You can also see all the messages from fixed solar panels on Home; it was the beginning of year 6, time for a new general checkup.

As Trucker reached Kerbin 6 months later, I needed to send up some thermal shields and parachutes to bring it down safely. I made this shuttle to bring two inflatable shields that could grab on Trucker. It was an awful, poorly planned mission with a lot of problems; unstable rocket, poor manueverability, power shortages, lack of an engine capable of multiple ignitions. This happens when I only have to do one small thing, without wanting to put too much effort into it. That cargo bay was a convenient way to stock both shields in a single flight, but it created more problems than it was worth. I later learned that I could have created multiple bind points within a fairing and it would have been much better.

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The ship releases its cargo...

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...that binds to Trucker. This part was tricky because I forgot additional power source on the probes, so I only had 15 electric charge to line up and grab Trucker

Trucker lost one solar power during the aerobraking manuevers to circularize orbit

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The probes make their cocoon around Trucker. I didn't name them at the time, but I do so now: Cocoonator

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I really wasn't expecting the remaining gigantor to survive reentry, but it did. Good job, Cocoonators!

Quote

The Dream Big* program was criticized for its high cost. Is it really worth to send such a gigantic ship to collect science on the outer planets, when multiple individual missions for every planet could have achieved the same goal for a fraction of the cost?

But we must remember that collecting science was never the main goal of the program. The Dream Big program ultimately aims at making the next step, from occasionally dabbling in space to truly conquering space, living in space stations, living off the available resources. Ultimately, even, learning to make out spaceships functional for long enough, that they could bridge the vast distances between the stars, and expand the reach of Kerbalkind through the galaxy. The science data from the planets, while important, is dwarfed by the plethora of data we are gathering daily on kerbal survival in space, kerbal adaptation to living in space, biological and technological resilience to all the hazards of deep space.

In this light, the recovery of Trucker marks an important milestone, and especially the incredible recovery of one intact faulty solar panel. Studying its reaction to space weathering will enable new breakthroughs in material science and a new generation of technologies to extend the operational life of our crafts

Walt Kerman, head of public relation, on the recovery of Trucker

*Note: Dream Big is not capitalized because it's the program's name, and not the ship name. The Dream Big program brough to developing and assemblying the DREAM BIG spaceship

7.5) DREAM BIG in the inner Kerbol system

Spoiler

Good thing I learned radiation management with Digger 1; doing so with the DREAM BIG would have been equally grueling, but with lag and long loading times included. Still, for now the active shields cover the ship. The main task is hardware maintenance. And it's definitely paying off, because I've never had a solar panel break down for neglect on a manned ship (and very few other broken components), while the unmanned vessels are all mostly or completely nonfunctional by now.

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An unidentified engineer is fixing a solar panel, broken as a result of somebody's breakdown

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Our brave engineer is crawling in the small space between the inner crew compartments, the fuel tanks, and the shields, to repair the crew compartment's life support systems.

The only exception, at some point I got a message about a broken solar panel. But I could not see it, until I went and looked up close

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The red cupola on the left was the same one broken around Duna, in the first breakdown-induced casualty (see 6.3)

See in the middle of the screen, between the "V" made by two of a Dolphin's solar panels? Here is a retracted solar panel that should not be there. What is a solar panel doing in that position?

It was forgotten from the very beginning of ship assembly. The very first model of Home had solar panels attached directly to the sides. It could only fit 20 or 30 of them, and experiments showed they were not enough to keep the greenhouses active around Jool. So I removed those panels and came up with the truss-mounted version. But those old solar panels were hidden by a bulge in the fuel tank (the same one that makes the central docking ports look bad. It's quite inconvenient to attach stuff. But then, I don't think they ever considered that anyone would want to really attach stuff to an S4 tank; after all, no sane person would ever use an S4 tank as anything but part of a disposable first stage. Hell no, probably no sane person would ever use an S4 tank at all. But here we are). There are 4 of them. I first considered editing the ship file to remove their dead weight, but it would be risky. Eventually I discovered EVA assembly, and I realized they could be useful spare pieces. Now I run regular upkeeps on them too.

Losing resources is also hurtful. It seems at every breakdown resulting in loss of a resource, I lose 10% of current stock of said resource. I have no idea if rocket fuel can also be lost in the same way (later EDIT: no, all rocket propellants can't be lost that way), I mostly lost ammonia. Anyway, my stockpiles are good for many more years, even partially depleted. Losing fuel/oxidizer is the only eventuality that would actually be dangerous

By the way, the manuever timer shows it's almost time for the first course correction manuever (plane change)

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No time constrains, so using only 10 rockets reduce risk of malfunctions. It also reduces fuel consumption on the glitchy lateral tank that was isolated from the rest

This brought Jool periapsis from over 1 MKm to within the moon system. It's now time to plan a second course correction, to find a path amid those moons.

In my previous missions I learned to effectively navigate the gravity assists for cheap injections in the moon of choice. But now there is a new threat: Jool's radiation belts

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The outer radiation belt, faintly outlined, fully includes the orbit of Tylo. In there, kerbonauts are exposed to 10 rad/h. That's the same level as Kerbin's main radiation belt, and twice as much as a regular solar storm. Even the shield would only negate half of it, and I don't have enough power to keep it active at Jool. In those conditions, kerbals are estimated to die within 15 days. I barely have time for quick missions to the inner moons before getting away as fast as possible. It's a pity, because Laythe and Vall are beautiful

The inner belt, starting just below Laythe's orbit, is what I call the Death Zone. Radiations level reach a staggering 200 rad/h, and they would fry my poor crew in an hour, two at most. To be avoided at all costs.

My normal approach for a Jool insertion uses a Laythe assist, but Laythe is too close to the Death Zone, so I will go for Tylo. A Tylo assist that would, ideally, send me straight to Pol. I spent a lot of time looking for a right trajectory.

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This path would get me straight to intercept Pol's orbit with a low intercept speed (600 m/s, which is the best I can get without many more assists), but it goes straight through the Death Zone. Rejected

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This one would get me to a nice Pol intercept. However, though it's not very clear in the image, that close approach only happens after two orbits. So I'd have to cross the outer belt twice. To keep only as last resort

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A very small deviation on the previous trajectory would raise my Jool apoapsis enough to intercept Pol when falling down, without a second pass through the outer belt. But now intercept speed is 1 km/s, too high.

As outlined in part 6.4, my budget for this manuever is 800 m/s at most, and I'm afraid even that relies on optimistic assumptions.

Finally, after many manuevers that would be perfectly good in the stock game but would have too many radiations, i have the right idea: after the Tylo assist, upon reaching Jool apoapsis, I perform a prograde burn to increase my periapsis over the radiation belt and intercept Pol at a later orbit without killing my crew. This will be a moderately expensive manuever; however, if I place well my apoapsis to intercept Pol's orbit, it will also result in a very low intercept speed, saving fuel overall.

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265 m/s for periapsis raising, and 250 m/s for intercept, including circularization. It makes me feel much better about my chances at making it back to Duna afterwards. The whole fuel cost for sending the Diggers around is completely eyeballed. I guess in an emergency I can always ditch a Digger to cut 80 tons of dry mass. I can ditch both Diggers if I can recover Digger 1 from Dres.

The original course correction, to set the right path on Tylo, is less than 1 m/s. The way every small variation in trajectory gets magnified by the gravity assist, the manuever is so fine, I can't pull the arms of the manuever node, but Imust write in the values manually, down to 0.001 m/s.

As I gradually move outward from Kerbol, though, I face another obstacle: not enough power for the radiation shield!

At 30 Mkm I started having power shortages. I fixed that by opening up every remaing solar panel available (I normally kept the shuttle's panels closed).

At 33 Mkm I had to shut down the greenhouses while the shield was working. By now the sunlight is not strong enough to grow plants, requiring more and more power to keep up.

At 36 Mkm I started using the main fuel cells to supply extra power during storms.

At 38 Mkm I started activating every single fuel cell left on the ship, down to the smallest ones producing 2 electric charge per second.

At 39 Mkm I finally had to shut down a couple of shields. Then 3, then 4.

Closing in on the 40 Mkm, I finally gave up. I knew from the start I couldn't keep up forever. My initial estimate of having power all the way to 50 Mkm was optimistic, but ultimately, it makes little difference. While I want to protect my delicate ship from radiation damage as long as possible, one or two storms earlier or later will make little difference. The huge S4 fuel tanks should be more than enough to cover the crew. And at least solar activity is finally beginning to go down to more manageable levels.

Here I got another big surprise: sheltered in the inner crew cabins, isolated from the environment by 150 tons of fuel on every side, my crew was still taking radiation damage. Turn the ship around as I wanted, I still was taking damage.

I put that information in my bug report along with the time warp thing. And I got answered, "well, duh! the mod does not take into account individual habitats, but it makes an average on the whole ship". In retrospect, seeing the same radiation value on all habitats should have tipped me. (I also reported that solar storm duration was increasing, and I was told that it's normal, storms get longer but less intense the farther from kerbol you travel. Which makes sense, I was about to suggest they did something similar myself. Except storms are lasting 2 full days, and intensity went down only from 5 to 4.5 rad/h. At least part of that is due to solar high, though).

It's a disaster! No matter how insulated are my inner cabins, having the greenhouses so directly exposed caused my crew to take damage, even if those greenhouses are empty. And if I turn the engines to the sun, the shuttles attached laterally have the cabins fully exposed.

The solution seemed straightforward: put all the crew inside the Diggers (unfortunately, a single Digger does not have room for everyone). Detach Diggers. I know for a fact Diggers can protect crew from radiations, having all crew cabins on one side (a lucky accident of ship building). Then dock again after the storm passed, in a lenghty process. At least fuel consumption is very small, I give only the smaller nudges with the RCS.

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The two Diggers being detached

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A spectacular accident caused by me being reckless with time warp and allowing Digger 3 (coming from the back) to clip inside Home. While in time warp, the game does not check for physical contacts.

Going on like that would be feasible, but a big hassle, what with having to go through this whole procedure at every single solar storm. I was still some 600 days away from Jool. Then I had the idea: so far I haven't looked much on the novelties introduced in 1.11, but perhaps EVA construction mode could let me shift some docking port to orient my crew cabins the right way.

7.6) Refurbishing the DREAM BIG

Spoiler

The EVA construction mode turned out to be flexible and easy to use, if not well suited to a ship of this size. Since I had the chance, I decided to also get rid of some broken parts

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Here I am dumping a broken parachute, while also experiencing weird clipping

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That rearward looking cupola is nice to see the rocket ejects, but it's fully exposed to the sun. Let's place a clamp-o-tron on it so I can place a Digger to block

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Digger 3 (or 4? They are identical) is now protecting the cupola. Of course I must remove it from there before making any big manuever. For small correction burns, I can use the Digger's own engines

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Here I discover two nonfunctional docking ports forgotten from a previous rework. I can put them to good use.

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I place the docking ports on top of the radiation shield piles, and link the Dolphins there. They are narrow enough to fit, barely

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Here Giuritto is carrying a docking port to the front of the ship, where I plan to put the two remaining Diggers

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Eva construction also carries some nuisances. Here I accidentally detached a nose cone from the FU Eve, and I'm finding I cannot put it back. I had to reload

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And here attaching a docking port sent a ripple that tore the ship in half

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And finally the job is done! One Digger was moved to the back to protect the cupola with its fuel tanks. The other Diggers are attached on top (I was concerned for their cupolas, but apparently they are close enough to the main body of the ship that they count as covered). In the middle I placed The Can, and the Dolphins are on top of the shield piles. Those shields may be inactive for lack of electricity, but they are still protecting my ship! Perhaps I should rename them passive shields now, though.

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Digger 3 seen from Digger 2

There is still one problem: with the engines towards the sun, the solar panels are not getting energy. Ok, the fuel cells cover it nicely. But it means I must turn the DREAM BIG by 90 degrees at every single storm, once engines to the sun to protect the crew, once panels to the sun for electricity. The DREAM BIG has plenty of reaction wheels and can make the 90 degrees turn in less than 1 minute, but that minute stretches to 4 or 5 with the lag. Then I am limited to x1000 warp during the storm, and with lag it's more like x200. Then I still have to open the electrolysis to restore the hydrogen stock (it will last for years, but I'd have to dump precious water if I don't use it), and I still am limited to x1000 because resource converters malfunction at high time warp.

So, it was slow progress. It took me real life days to move forward.

  :rolleyes:hey, what about us? For you it's a few days, but for us it's years!

Huh, ok. Can't really complain, my crew has it wors- NO! You guys are living in a handsome space palace! It's every space enthusiast dream! And you are paid handsomely for it! So shut up and let me complain!

7.7) The orbit must go on

Spoiler

This was the last serious problem, the last "CRAP, it's mission failed" moment. The remaining year before Dres landing was fairly uneventful.

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This shows a common moment of solar storming. Every ship is calculated independently, even though they are very close. I seem unable to delete the parts I dropped while refurbishing the ship

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One year to Jool, and we have the first close sighting. "close" in that you must stick your nose very close to the window to see it

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It's the new year, time for a new round of general maintenance. Despite being subjected to storms for the first time, the ship is in surprisingly good shape. I also had less stress-induced malfunctions. I'm beginning to suspect radiations improves humor

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Here a breakdown caused a loss of... food. By opening a valve. I wonder how they are keeping food aboard this ship. The other malfunctions have been very benign, being fixable without any lasting harm

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Still more images from the maintenance. 400 days to Jool, the ship is in good shape

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Scheduled maintenance is also performed on Digger 1

And regarding Digger 1...

7.8) Dres and back

Spoiler

After 2 years (2 weeks in real life), Digger 1 has reached Dres!

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Injection burn

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And obligatory engine maintenance afterwards

Once in orbit, landing on Dres is easy. For the first time I'm now not trying to land close to the canyon. I've seen it already, and it's unsuitable as rover driving circuit.

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A combination of irregular terrain and poor piloting almost made Digger 1 fall. Only a quick activation of the RCS saved the day.

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It is now my third or fourth Dres landing, so I can attest that the conspiracy is wrong, and indeed the dwarf planet is real. I just wish it weren't the case: the canyon was a let-down, and there are no other noteworthy features on Dres. And it's very hard to reach for little value. If Dres didn't exhist, nothing of value would be lost, and performing grand tours would be much easier.

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In a childlike show of my dislike for the planet, I also cheated in a drain valve to dump all my human waste on the planet. Then I reloaded, I don't want to have cheated pieces on, even if they are useless. More information on this little stunt on the Anti-Dres awareness thread

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Orbiting again, rejoining Dolphin 2. Actually, in this pic I already rejoind, and I am now detaching them for good

I'm now sending my crew back to Kerbin. I have food for one and a half year. The Dolphin would surely be able to reach Jool in that time, but the crew is already suffering from radiation poisoning, and they'd be subject to Jool's radiation belts. And I yet haven't tested how well a Dolphin takes radiation. I am fairly sure I can reach Kerbin safely if I go fast, the sun activity is not too high at this moment. I just don't want to stretch my chances.

Digger 1 will stay at Dres for 200 days waiting for the transfer window, then move back to Duna, to wait for the return of the DREAM BIG.

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Dolphin 2 leaves Dres

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I staggered the solar panels to provide adequate power regardless of ship attitude. But now that I know EVA construction, I am moving them to maximize exposition

xLB4Zsc.png

Not having to worry about fuel, I can make the trip very fast. I will be back to Kerbin in less than 1 year. 8 km/s intercept speed; I tested a Dolphin up to 7 km/s, and it survived reentry. In the worst case, I will just slow down first

For the 3 km/s burn I tried to install one of the mods suggested by @JupiterJaeden. It didn't work. I copied the mod in the directory, but it made no effect. I don't know if I'm doing something wrong or if it's a version compatibility. Dolphins are much more manueverable than Trucker, with more solar power, even at Dres, and less mass. I should be able to keep the engines close to 10% even at Eeloo. Still, 3 km/s is a long burn with ion engines. I performed it in background during an online D&D session with friends.

syeDoPD.png

I could have made it even faster, but I didn't see much of a point to it. Or to prolong the engine burn.

Edited by king of nowhere
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Maybe someone else has suggested it, or you don't want to, but have you considered rotating crew?

Not sure how difficult it would be, but if you did a Kerbin assist then you could send up a fresh crew during the flyby, the capsule would just need a lot of DV to reach escape velocity, dock, and then return to orbit.

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