Questions for Realictis level of difficulty

[Catalyst_Kh]

The problem is rather to come back from Venus. Gravity and orbital speed are nearly the same as for Earth (they are a little lower), and because of the thick atmosphere you'll experience a lot of drag. That lander is way too small to be able to come back. Also you should make it as slick as possible because drag really matters on Venus.

That was a big blunder of mine! I didn't know that, thank you once again for nice tips.

Now i have these two launchers constructed for Venus mission and can't figure out what should be a better one:

Spoiler: Which launcher is better?

Second picture is what drops into Venus atmosphere and third picture is what i plan to take off from Venus's surface (after detaching heat shields and parachutes of course).

Taller one have less drag, but also have much less fuel in it's first stage. What would be more beneficial - extra fuel with extra drag or less fuel with less drag?

 

[Catalyst_Kh]

Only first stage will have extra drag, 2 and 3 are identical.

Also i found very interesting idea for Venus. If my man can escape Venus at all, at the very last pint of fuel, and grab any orbit at all - he doesn't have to be able to reach refueler station - now this station have it's one android operator, which allows us to use this station and maneuver it to collect our man in his totally empty rocket and refuel him!

The man only needs to escape from Venus on his last pint of fuel, he can burn everything to the last, it gives him a lot of extra efficiency - we don;t need to upload any extra fuel from Venus ground, which makes entire system with all stages much more efficient.

 

[Altaïr]

No refueling. 160 tons from take off to LEO by huge launcher, in single launch, and 122 tons of those 160 reached Moon's SOI

But I don't understand how you could reach the Moon with 122 tons starting from 160 tons in LEO. I tried myself by assembling 2 ships:

Those docking arrows are really cool

Now I have a bit more than 160 tons in LEO, but when I burn to the Moon:

I only have 80 tons remaining. And that's taking into account the empty stage, otherwise I rather have 71 tons:

How did you manage to get 120?

That ship is really beautiful!

But we need a fair game! No cheating!

Thanks. Actually I don't use it a lot, that was originally a launcher able to launch 1000 tons to LEO in IRIS. I also use it sometimes to troll other people by launching their launchers to orbit
But yeah, it's cheating, it's mostly for the fun. I mostly play without cheats myself. Even that launcher is not that cheated, there are no clipped parts. It's built outside of the build area, and the engines generate no heat too. That was the only way to not have it look like a cathedral

I read your topic with your travel to Mars in IRIS and achieving all missions in two flights, with gas station first. It was very interesting and entertaining! But at Realistic level it has totally new plain of interest - a challenge, a sport interest. For example, you need around 4.9 km per second to escape Mars' Soi at Realistic. And you don't have any gas stations from previous launches.

Yeah, Mars is on another level compared to the Moon. However the 4900 m/s are not a much bigger problem. Speeds are lower in IRIS but engines are less efficient too. That ship would be able to get back to orbit:

It has 5440 m/s of ΔV, and a TWR of 1.2 on Earth means 3.16 on Mars, so I won't lose much to gravity.

For example, try your aerobreaking strategy to save a lot of fuel and see what the result will be - you are up to a big surprise.

Would it be... toasty?

Taller one have less drag, but also have much less fuel in it's first stage. What would be more beneficial - extra fuel with extra drag or less fuel with less drag?

Hard to say, both have their benefits but I would have to try myself. Have you tried to reach LEO with that launcher? The orbital speeds are close, it should be 7216 m/s for Venus.

But doing it in a single launch will be hard for sure.

 

[Catalyst_Kh]

I also use it sometimes to troll other people by launching their launchers to orbit

ROFLMAO - that is nice one!

But I don't understand how you could reach the Moon with 122 tons starting from 160 tons in LEO.

By ion engines and very low periapsis. But it took many tens or rounds around Earth to accumulate the whole 3km ΔV with just two ion engines and big ship. So this is reasonable only for making a record or beating a challenge. While normally it would be faster and easier to just use either orbital refueling or additional carrier from LEO, like yours at your pictures, which will simply propel all 160 tons out of Earth SOI with just a few orbits.

Would it be... toasty?

No, it works well and slows down as planned, but it has unexpected consequences for entire strategy, which must be dealt with, or entire challenge may be failed.

Hard to say, both have their benefits but I would have to try myself. Have you tried to reach LEO with that launcher? The orbital speeds are close, it should be 7216 m/s for Venus.

But doing it in a single launch will be hard for sure.

Both are reaching LEO at last fuel, but this makes only small reserve of power, which could be not enough to overcome extra atmospheric drag.

And i can't add more fuel, since all stages are already almost overloaded. To make more fuel means totally replacing engines structure, which will add even more weight and demand even more fuel to overcome extra new weight. Thus entire Venus rocket will become enormous - such rocket will be much heavier than 160 tons and thus one launch mission can't be successful.

While now i still have some room for optimizations and if this 3-stages rocket will not escape Venus i will at least see how much i need to add, and where exactly, and can measure drag too, then maybe i will come up with optimizations, which can fit in 165 tons of total payload to LEO and bring those 165 tons to LEO with best fuel distribution between Earth stages. While last time i optimized it only for Mars mission, but now with new sizes cumsumption of Venus complex it is not optimal and loses some tons from maximum possible.

 

[Catalyst_Kh]

I made stage balancing optimizations and improved my take-off trajectory, now i can bring to LEO 185 tons of pure Payload in one flight. When 185 tons are counted only after detaching 3rd take off stage.

Thus now i have some room to make a stronger Venus rocket.

 

[Catalyst_Kh]

Finally went to Venus:

 

[Catalyst_Kh]

I caught a nasty bug. Please help me to fix it.

Sometimes all my rockets in entire world instantly gets speed twice or many times slower, then they got just a second before. And if i load any other older quicksave - they are already broken there too, already slowed down.

If i restore the entire world folder with all it's contents from backup - then it fixes things, and even newest quicksaves start to work properly, even though backup world itself is much older, than newest quicksaves were made.

But this time my last fix doesn't work.

When i dive into Venus atmosphere at steep of 10.9 km per second, after just entering Venus SOI, somewhere near periapsis inside atmosphere my speed halves instantly, like immediately, in one second, and i can't get to Venus orbit again, since i am falling now. If i load quicksave from just half a minute of Venus atmosphere - i already have halved speed there too.

And now if i quit the game and some back - each my rocket or debris in entire solar system are halved in speed, or even more than halved. Thus entire world is broken permanently.

And if i replace world from backup it fixes all saves at once, BUT when i dive into Venus atmosphere - the world brokes again. But if i don't dive and just fly by Venus ang go away in outside space - then everything works well, no bug occurring.

What causes the bug? How to fix it?

 

[Catalyst_Kh]

I have newest steam version, legal and updated, and all last versions of mods installed. I just switched off all mods entirely, made one another attempt, to find out if mods are responsible, and this bug happened again!

A little later after this point:

It always happens before periapsis. Sometimes close to it, sometimes long before it, like just little later than my position.

But this time when i pressed "Revert 30 Sec" in game menu it reverted me back to the point at the picture above and world was fixed again!

Also i spotted this time, that the bug happened exactly at the moment when i switched 2x time speed to 1x, looking at my rocket (not game map). I hope this may give some clues.

Please help.

 

[Catalyst_Kh]

I tried once again with no time acceleration switches at all and it worked well. 27 km was just a little too low and i didn't dive out from Venus to it's orbit, thus i need to reenter Venus at a higher altitude for aerobreaking.

But when mods were active - i tried steady 1x time speed and it still got broken anyway.

So clues are controversial, i can't figure out which procedure is responsible for this breakdown.

 

[Catalyst_Kh]

Just as random guess i switched off world clock and time warp clock entirely, so it is never shown, and then with all mods active and working and with all other "dubious settings" from mod i dropped in Venus atmosphere once again and now it worked well.

Thus i suspect world clock function in Vanilla mod somehow ruins the game.

After diving and aetobrecking to 31 km above Venus i got nice orbit, it needs correction with second dive, so it is better to dive at 30 km in Realistic.

 

[Catalyst_Kh]

Bug happened again without world clock present. Thus clocks are not responsible. Also once bug happens, each time i press timewarp button it happens again and again, speed instantly drops in 2-4 times in one second with each time timewarp button is pressed.

Thus time warp functions cause the bug - this is certain. But is it from one of mods or it is inherent in the game code i don't know. And the more important - how to avoid the bug? What i don't need to do, which my actions causes it?

 

[Catalyst_Kh]

Looks like this happens only if i load a quicksave somewhere in game, after the initial game launch. Them from quicksave point somewhere soon this permanent world damage will occur. But if i launched the game and pressed resume - i can do whatever i want, switch time speed rapidly and very often, and bug doesn't happen, all works fine until i make at least one loading of quicksaves.

 

[Catalyst_Kh]

Bug almost never happens at 1x speed, it may happen at 1x only if i made a lot of timewarps just before entering atmosphere.

 

[Catalyst_Kh]

I went to Venus by single launch from Earth without any help from other rockets, landed on Venus, got back, and when i was entering Earth atmosphere i still had 15 tons (!) of unspent fuel left.

But as we expected - i barely escaped Venus, on last pints of fuel, and that android driver with gas tank was exactly needed to catch up my astronaut in orbit.

It would be more optimal to just overload first stage of Venus rocket with more fuel, taken away from gas station module, to keep the same total weight of payload, but to have more leeway for escaping Venus through thick atmosphere.

Spoiler: Return home picture:

 

[Altaïr]

I caught a nasty bug. Please help me to fix it.

Yes, it's a known bug, it's already been reported. It's been noticed with Mars, and I already had it with Mercury too. That one is hard to bypass. It looks like it's only triggered by a few particular saves, but once it starts happening the only way to make it stop is to load a quicksave that works then restart the game. That's my feeling at least.

I went to Venus by single launch from Earth without any help from other rockets, landed on Venus, got back, and when i was entering Earth atmosphere i still had 15 tons (!) of unspent fuel left.

But as we expected - i barely escaped Venus, on last pints of fuel, and that android driver with gas tank was exactly needed to catch up my astronaut in orbit.

It would be more optimal to just overload first stage of Venus rocket with more fuel, taken away from gas station module, to keep the same total weight of payload, but to have more leeway for escaping Venus through thick atmosphere.

Spoiler: Return home picture:

View attachment 96568

Well, congratulations on that one, I never attempted it myself but that's a performance for sure

 

[Catalyst_Kh]

Now i want to mount a one launch only all-at-once Jupiter mission at Realistic. As i understand double aerobreaking will count as success for both Jupiter achievements, while visiting all his moons will not be hard, since they don't have much gravity, so i can take little rocket, and thus a big fuel canisters can be brought in voyage for the remaining weight limitation of one launch.

 

[Catalyst_Kh]

And i will try to break my mass to the Moon in one launch record once again.

 

[Altaïr]

All Jupiter's moons in a single launch... I wish you good luck. The moons gravity is light, but Jupiter's gravity is huge. Also you have to go there. Time to use the VEEGA technique, this is where it really shines

 

[Catalyst_Kh]

Oh, I have to finish that challenge!
...

There are nice textures on planets and looks like good complete solar system. Is it still working with new version? Is it good and correct 1:1 to reality in distances, gravities and orbits?

It is from that old topic: Engines are expensive Challenge

Please give me the link to download this custom solar system, or to it's forum topic.

I still can't understand how to add custom textures to the game. Even with new custom solar systems SFS shows no textures, when textures are present inside custom solar system's folders. And if i add textures to \Spaceflight Simulator_Data\Custom Solar Systems\Example\Texture Data folder - they simply disappear after game start.

My Jupiter all-in-one mission is on hold so far, i was little busy with other things, but it is coming soon. I also improved my launcher a lot, now i can bring 190 tons to LEO, if payload is tight in size, and 185+-, if payload consumes more space. It looks like this now:

Spoiler: Launcher

Having less fuel at the top in favor of nice caps-spikes makes more ΔV even with straight vertical line from ground to space, but in addition, it also allows to make better take off trajectories, since i can turn to horizontal angle much more and much earlier and experience less atmospheric drag, than before, which adds one more benefit in free horizontal +ΔV to LEO.

 

[Altaïr]

There are nice textures on planets and looks like good complete solar system. Is it still working with new version? Is it good and correct 1:1 to reality in distances, gravities and orbits?

It is from that old topic: Engines are expensive Challenge

Please give me the link to download this custom solar system, or to it's forum topic.

This is old (I totally forgot that challenge to be honest) but I think it was ACSS. Here's the latest version posted to my knowledge.
However the planet format changed, it worked well at that time but the pack has only been partially ported, all the terrains were removed. The problem is that the author ceased his activity. He delegated the maintenance of the pack to another member but he also stopped.

In realistic mode I don't know but if they didn't make the adaptation work it probably won't work.

I still can't understand how to add custom textures to the game. Even with new custom solar systems SFS shows no textures, when textures are present inside custom solar system's folders. And if i add textures to \Spaceflight Simulator_Data\Custom Solar Systems\Example\Texture Data folder - they simply disappear after game start.

You don't add them into the good folder. The Example folder is the game solar system. That folder and its content is generated by the game itself (hence why your textures are removed after you started the game), it's just supposed to be a starting point for planet makers.

If you want to add a texture you have to make your own solar system (it can be a simple copy of the Example folder), add the texture to it, and create a new world that uses that system.

 

[Catalyst_Kh]

I made a copy of Example world and named it "Example textures", then added textures to the cope, from some texture pack zip file, which downloaded from one of forum threads here. It doesn't works, no textures are shown. Here is the folder screenshot:

Spoiler: folder

Also i installed those two custom worlds:

Complete Solar System , With Accurate Orbits

True Scale and Distance Solar System (TSADSS) FULL RELEASE

Both those worlds works fine, but they also doesn't show any textures in game, nowhere at all, thought there are a lot of texture files inside those worlds folder. I also copied textures from both these custom worlds to my "Example textures" folder and it disn't help too. No textures in the game so far.

 

[Catalyst_Kh]

So, here we go for Jupiter all-in-one-launch mission.

I decided not to give up on Moon just yet and tried another interesting idea. I will still use VEEGA path of course, since i was not able to invent any better trajectory.

But i will not be slingshoting from Moon to Venus directly, since it has very little +ΔV bouns even if i catch the Moon in it's best position for my trajectory, while if Moon's position is not best, i might end up burning even more fuel from Moon, than i would burn from Earth periapsis directly to Venus, or instead i will be burning extra fuel near Venus itself to fix bad approach trajectory, which Moon gave me, which will totally negate my +ΔV bonus from Moon, even if i will catch such a bonus at all.

But i will use Moon slingshot to get me to the maximum apoaspis inside Earth SOI circle. In this way i will get 2000Mm+ apoapsis for the price of only 375Mm (which is enough to be picked up by Moon). Thus i plan to save some fuel, or in other words to get a free +ΔV speed bonus from the Moon.

But that plan didn't work well, since i need to be back to Earth's very low periapsis, from which i can burn one last time to the Venus with optimal trajectory, when the time is right. And burning at 2000Mm+ apoapsis to lower periapsis kind of negates any +ΔV, since i have to slow down and give it all back. Very sad. And if i burn to Venus from high periapsis i will once again lose all +ΔV gain. But still - it was interesting to try.

First time i overdid it - Moon gave me too much assistance.

Spoiler: 1

So i had to reload and fly by at higher distance from Moon, to grab less gravity assistance.

Spoiler: 2

Though when i performed it - i had an unexpected obstacle - the Moon was catching me again and again at my very eccentric Earth orbit and ruined my Earths's periapsis each time. :facepalm:

Thus i understood, that i need to burn to Venus earlier, i can't wait many circles, since constant periapsis correction after each encounter with Moon eats fuel.

So when i made my free upload from 375Mm periapsis to 2048Mm, i didn't wait long and burned to Venus directly from Oberth from Earth (from very low periapsis). But Venus wasn't there of course.

So i had to load quicksave and redid it all from before i reached Moon, i waited a little, and when Earth and Venus were in more favorable positions in solar system to start VEEGA path - i caught Moon and after just one upload to 2048M i went to lowest Earth periapsis and from there directly to Venus.

As i understand the most beneficial way would be to catch up Moon second time en route from 2000Mm+ to Earth (or several orbits later), to use it for little slowing down, to make it cheaper to lower periapsis to Earth to the minimum again, in order to make one last burn to Venus from there. But that is too complicated and probably once again will gain very little +ΔV, thus i gave up on this idea. So, direct transfer from Earth's low periapsis to Venus is simply more comfortable.

 

[Catalyst_Kh]

Here is a new Moon record by the way. It is already close to the maximum possible according to my strategy:

Spoiler: Moon record

 

[Catalyst_Kh]

My very first VEEGA attempt was not good enough. I caught all 3 gravity assists, but i took too little acceleration from them. Thus after second slingshot from Earth i still was very far away from Jupiter.

Spoiler: 1

I tried not only VEEGA, but also VEEEGA and VEEEEEGA, and still didn't get to Jupiter even close.

And then i understood, that i am simply approaching planet with too little vector difference. Thus i simply reloaded earlier and took more burning from Earh to Venus, to approach it from the side.

This time i overdid it and got too much gravity assist, but the time i completed VEEGA i was half way to Saturn and had to reload again to slow down a little at the last assist. And here we go:

Spoiler: 2

Now the Jupiter will meet me in 3 turns and i still have more than 149 tons left! If i would not burn too much extra to Venus in the first place, o could bring to Jupiter the whole 150 tons of mass.

It is very surprising, that it took 21 tons of fuel get from LEO to Moon, and only 4-5 tons of fuel to get from Moon to Jupiter! Though i didn't even detached anything en route.

 

[Catalyst_Kh]

Altaïr, I want to say one special big thanks for your great mod Closest Approach line.

New version of this mod simply shows where the resonant orbit will be, so there is no need to catch up on anything, no need to line up anyone in advance - one may just go to Venus any time from anywhere and even if Venus is not there - Closest Approach lines will just offer the cheapest burns to transfer to resonance orbits, one may pick any resonate ratio from it, whichever they desire!

The same is with any other next slingshot body in route - nothing should be aligned in advance, this mod will always show how to resonate with just very little burn and to catch up with the target with the best approach vector possible.

That is so great and easy now. Now there is no need for calculation of any kind, like perihelions plus aphelion plus diameter of sun and so on.

The only thing needed is to create this optimal vector in the first place - and that is all.