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king of nowhere

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  1. king of nowhere's post in How to do a Duna aereobrake... a safe one was marked as the answer   
    aerobraking is a matter of speed. if you go too fast, too shallow, you burn. but if you don't go shallow, you don't brake.
    hencefore, what makes duna uniquely suited for aerobraking is not its thin air - which is actually no different from other upper atmospheres. duna is unique because it is small.
    you arrive at a planet with your intercept speed. for a kerbin-duna transfer, it's generally 400 to 600 m/s. then you fall towards the planet, so you have to add the escape velocity from the planet to your intercept speed. on kerbin, this would result in speeds well over 3000 m/s, which incinerate most parts. eve is even worse, and laythe is only slightly better. but duna has a very low escape speed. you can reach it from interplanetary, and still be no faster than 2 km/s, which is totally survivable.
    still, heat sensitive parts - like some solar panels - won't survive that. so make sure there aren't any; use retractable solar panels, those are very strong, or put your solar panels in shielded positions.
    as for height, you can only figure it by trial and error. my experence is different from @Vanamonde, I generally get by with periapsis between 20 and 25 km. perhaps the difference is because i want to brake, but to stay in duna's orbit, while he wants to land directly. regardless, save the game before the encounter and try different periapsis until you find the right one.
  2. king of nowhere's post in Why won't KSP recognise my space station as such? was marked as the answer   
    no, there aren't any special requirements. the tracking station assignment is done according to some parameters that I don't know, but they are quite random. my last ship was dubbed a plane just because it had a Mk3 crew cabin, even though it had no wings.
    anyway, it makes zero difference. if it's to fulfill a contract, then as long as it has the crew capacity and the parts specified, you are fine. if you just want to see "space station" in the tracking station, you just have to manually set your station as such.
    go to your station, select any crew pod or probe core, right click on it, "configure vehicle name". there you can also decide if your vessel is a station, plane or whatever
  3. king of nowhere's post in 1.12 decoupling docking ports? was marked as the answer   
    I have bad news and good news.
    the bad new is, it's a know bug, and indeed there is nothing to be done, except hacking the save.
    the good news is, it's a predictable and reliable hack, and somebody made a tool for it.
    check this kml editor, it can edit save files in many ways, and it does fix broken docking ports.
    I never checked its other functionalities, but I did use it to save my own mission when I had this bug myself, and I can attest that it is reliable, it works just fine, and it does not mess up anything else.
     
    Also, if you destroy the docking port with the intent of fixing it later with eva construction, there is a good chance that breaking a broken docking port will crash the game.
  4. king of nowhere's post in spawn a vehicle on specific planet? was marked as the answer   
    the cheat menu is your friend for testing.
    perss alt-f12, a menu opens. there is a cheat section. you can teleport to any orbit you want.
  5. king of nowhere's post in Ion engine usage? was marked as the answer   
    it's normal, ion engine drains lots of electricity. You have two options:
    1) add more solar panels/RTGs
    2) use them ion engines at low thrust.
    if you pick 2), i recommend the persistent thrust mod, that will let you use your engines during time warp. it's a real time saver.
  6. king of nowhere's post in how would i retrieve a spacecraft that is orbiting the sun? was marked as the answer   
    do the ship has still fuel? assuming it has, you are still close enough to kerbin that you can just set kerbin as target, point towards it, and burn.
    else, if you have little fuel, your orbit is very similar to kerbin, you should be able to return there in the next orbit. set kerbin as target, you should see a close approach marker. if kerbin is in front of your ship during the close approach, then burn retrograde - while your orbit is still touching kerbin's orbit! important - and watch the marker get closer until you get an encounter. if kerbin is behind, then burn progade instead. this is actually not difficult, but I have no idea how much experience you have in interplanetary traveling.
    if the ship has no fuel, you need to send a rescue mission. send another ship in solar orbit, and do a rendez-vous just like you would do around kerbin. only, it's going to be a lot slower.
    Regarding needs, if you can strap 30 pollux boosters on a ship, you can go everywhere. I suspect your ship and flight was very inefficient, else you wouldn't just be in solar orbit, you could go all the way to eeloo and back.
  7. king of nowhere's post in Difference between Hohmann transfer and "normal" transfer? was marked as the answer   
    they are the same thing. the description of the hohmann transfer says two prograde burns, because both are prograde from the perspective of the sun. in the capture burn, you're still burning prograde compared to the sun, because the planet is going faster than you and you must match velocity, at least enough to get captured.
    in ksp, when doing a hohmann transfer to an external planet, you'll see the planet "sneaking up" behind you. at this point the perspective changes to that of the planet.
  8. king of nowhere's post in Why do I keep landing Retrograde? was marked as the answer   
    the onion pod is very draggy. draggy parts tend to move backwards, that's why your ship spontaneously orients itself like it does. use a more aerodinamic crew pod in its place.
    though, like @jimmymcgoochie said, there's no reason to want to enter point-first.
  9. king of nowhere's post in Eeloo Capture Burn Way Off dV Map At 2713m/s? was marked as the answer   
    No. You are misreading the deltaV map.
    You are in LKO. from there, according to the map, you need 930+1140=2070 to reach an Eeloo intercept, plus up to 1330 to equalize planes, plus 1370 for capture. total 4770.
    But, as I said, the map is not reliable when significant inclination is involved. You can save some of the price of changing inclination. So the only thing you can tell from the map is that you'll need somewhere between 3500 and 4700 m/s.
    The alexmoon tool, though, IS very reliable for those kind of transfers. If it says you need no less than 3657, then you need no less than that, period. That's the best possible trahjectory, if you're really good and really lucky you may save 20 m/s over that, at most.
    By the way, if you tell the alexmoon tool to make a plane change, it will still not work as the map. the map assumes you reach the orbital node, then make a normal burn to zero inclination. the alexmoon will calculate the best, and that will often entail small plane changes that still leave a lot of inclination but do end up getting the lowest intercept cost for unfathomable reasons.
    So, your craft with 3461 m/s cannot reach eeloo's orbit. Well, not unless you play smart.
    First thing in your favor: orbit does not mean low circular orbit. both the deltaV map and the alexmoon tool assume that you end up in a circular orbit, which requires additional braking. You can brake enough to capture around eeloo, stay in an elliptic orbit, it will save some fuel. 200 to 300 m/s, not sure. anyway, you may just barely have enough to get captured into an elliptic orbit. I wouldn't count on it, though.
    What you do have in your favor is that you can make gravity assists. Now, if you're in year 9, you're in trouble, because the only source of gravity assists in the outer system is jool, and the jool-eeloo transfer window happens between years 8 to 10. During that time, you could take a jool flyby (for 2000 m/s from LKO) and get a free gravity assist to an eeloo intercept, with low intercept speed. Now you can still take a jool flyby, but intercept speed on eeloo will be a lot higher. and jool-eeloo windows are every 15-20 years. You could take a trajectory spanning multiple orbits too. Anyway, that's very difficult stuff. if you aim for a straight transfer, then no, your ship does not have enough fuel.
  10. king of nowhere's post in Not new but I think this question will fit here was marked as the answer   
    I would further add that fuel transfer through a claw is allowed at normal difficulty settings. at harder settings, by default it is not
  11. king of nowhere's post in Are items in a cargo bay protected from aero drag? was marked as the answer   
    no, stuff inside the cargo bay is protected from drag. that's the purpose of a cargo bay.
  12. king of nowhere's post in Interplanetary crafts with huge dV was marked as the answer   
    1) i don't. I use transfer windows and gravity assists to reduce deltaV cost as much as possible.
    If I still need lots of deltaV, I use ions. If ions are not an option, I use nuclear. All things you won't do.
    So, if you want to build ships with lots of deltaV with only LFO, the only thing you can do is build a huge ship with multiple stages. No other way.
    The rocket equation states that deltaV=ln(Mw/Md)*Vex: that is, the deltaV is equal to the logaritm of the ration between the wet mass (Mw) and the dry mass (Md) of your ship, times the velocity of your exhaust gases (Vex) - which is equal to Isp*g.
    So, to increase deltaV, there are only two things you can do: increase Isp, or increase the Mw/Md ratio. You don't want to increase Isp, so you've got to increase the Mw/Md. Which goes threefold:
    a) reduce the weight of the payload. self-explaining
    b) increase the amount of fuel. again, self-explaining
    c) use multiple stages. As the amount of fuel you bring increases, the mass of dry fuel tanks increases too. And of course, to lift all that stuff, you need a big heavy engine. So after you burned most of your fuel, you want to ditch all those empty, useless, heavy spent fuel tanks. And you want to ditch that big powerful engine that's no longer needed, and use something smaller and lighter instead. Drop tanks are also an option.
    Still, you can't prevent the mass from skyrocketing fast as you increase deltaV. Say your probe weights 1 ton, and you want 2 ton of fuel to give it 3 km/s. then if you want to add 3 more km/s, you need to make another stage with the same 3:1 ratio between dry and wet mass, so you need 9 tons. An additional 3 km/s will again require three times more mass than before, so 27 tons. Three more km/3, to bring the total to 12 km/s, and you're at 81 tons. And then 240, and so on. Past a certain size, rockets become hugely impractical. Which is why people prefer to use orbital mechanics to reduce deltaV requirememnts as much as possible, and to use more efficient engines.
     
    This game lets you "cheat" by mining new fuel everywhere cheaply. that also reduces the deltaV required. of course, if you're using kerbalism, then you're not supposed to use that - or you're supposed to use the kerbalism isru functionalities, which make refueling less practical than the alternatives.
     
    2) it's not exactly required that high deltaV=low thrust; the rocket equation has nothing on thrust. However, there are two practical factors that link high deltaV to low thrust:
    a) to maximize deltaV you want an engine optimized for efficiency. those tend to have lower thrust
    b) to reduce your dry mass you want a smaller engine. and of course this means less thrust than with a bigger engine.
    So, nothing to do there. you want to maximize your deltaV, you can do it by sacrificing thrust.
    Regarding your concerns with kerbalism, yes, it requires a lot of additional life support resources, but not too much. in the end, the mass of the food and water and oxygen is still a pittance compared to that of the living space. My suggestion there is that it's still a lot more convenient to add more supplies for a longer trip, than it is to add more fuel to travel faster. One kerbal can live one year with less than 100 kg of resources. To shorten the trip by one year, you could easily need to double the mass of your ship. Put three redundant units for everything essential, and you'll be fine regarding malfunctions, too. you can easily last 20+ years that way if your ship is well made. Again, it's a lot cheaper than making a ship three times bigger to have a shorter trip.
     
    3) you can take a look at my kerbalism grand tours linked in my signature; but the short answer is, with a BIG ship. Of course, a smaller crew would allow a much smaller ship either, and I like to put additional functionalities.
    the one that most closely resembles your mission parameters is Bolt, from my second mission; a relatively small ship, only 4 crew members. Only living space was 4 hitchhicker containers, a lab some cupolas (all stuff that reduces stress). the living space itself was about 50 tons, and with roughly 10 tons of supplies I could have lasted almost 30 years. Still, to avoid isru and make a grand tour, I needed a good 20 km/s on the main ship. Which I got by a multiple drop tank design, and it raised the total mass up to 5000 tons. even using nuclears.
  13. king of nowhere's post in Interplanetary crafts with huge dV was marked as the answer   
    1) i don't. I use transfer windows and gravity assists to reduce deltaV cost as much as possible.
    If I still need lots of deltaV, I use ions. If ions are not an option, I use nuclear. All things you won't do.
    So, if you want to build ships with lots of deltaV with only LFO, the only thing you can do is build a huge ship with multiple stages. No other way.
    The rocket equation states that deltaV=ln(Mw/Md)*Vex: that is, the deltaV is equal to the logaritm of the ration between the wet mass (Mw) and the dry mass (Md) of your ship, times the velocity of your exhaust gases (Vex) - which is equal to Isp*g.
    So, to increase deltaV, there are only two things you can do: increase Isp, or increase the Mw/Md ratio. You don't want to increase Isp, so you've got to increase the Mw/Md. Which goes threefold:
    a) reduce the weight of the payload. self-explaining
    b) increase the amount of fuel. again, self-explaining
    c) use multiple stages. As the amount of fuel you bring increases, the mass of dry fuel tanks increases too. And of course, to lift all that stuff, you need a big heavy engine. So after you burned most of your fuel, you want to ditch all those empty, useless, heavy spent fuel tanks. And you want to ditch that big powerful engine that's no longer needed, and use something smaller and lighter instead. Drop tanks are also an option.
    Still, you can't prevent the mass from skyrocketing fast as you increase deltaV. Say your probe weights 1 ton, and you want 2 ton of fuel to give it 3 km/s. then if you want to add 3 more km/s, you need to make another stage with the same 3:1 ratio between dry and wet mass, so you need 9 tons. An additional 3 km/s will again require three times more mass than before, so 27 tons. Three more km/3, to bring the total to 12 km/s, and you're at 81 tons. And then 240, and so on. Past a certain size, rockets become hugely impractical. Which is why people prefer to use orbital mechanics to reduce deltaV requirememnts as much as possible, and to use more efficient engines.
     
    This game lets you "cheat" by mining new fuel everywhere cheaply. that also reduces the deltaV required. of course, if you're using kerbalism, then you're not supposed to use that - or you're supposed to use the kerbalism isru functionalities, which make refueling less practical than the alternatives.
     
    2) it's not exactly required that high deltaV=low thrust; the rocket equation has nothing on thrust. However, there are two practical factors that link high deltaV to low thrust:
    a) to maximize deltaV you want an engine optimized for efficiency. those tend to have lower thrust
    b) to reduce your dry mass you want a smaller engine. and of course this means less thrust than with a bigger engine.
    So, nothing to do there. you want to maximize your deltaV, you can do it by sacrificing thrust.
    Regarding your concerns with kerbalism, yes, it requires a lot of additional life support resources, but not too much. in the end, the mass of the food and water and oxygen is still a pittance compared to that of the living space. My suggestion there is that it's still a lot more convenient to add more supplies for a longer trip, than it is to add more fuel to travel faster. One kerbal can live one year with less than 100 kg of resources. To shorten the trip by one year, you could easily need to double the mass of your ship. Put three redundant units for everything essential, and you'll be fine regarding malfunctions, too. you can easily last 20+ years that way if your ship is well made. Again, it's a lot cheaper than making a ship three times bigger to have a shorter trip.
     
    3) you can take a look at my kerbalism grand tours linked in my signature; but the short answer is, with a BIG ship. Of course, a smaller crew would allow a much smaller ship either, and I like to put additional functionalities.
    the one that most closely resembles your mission parameters is Bolt, from my second mission; a relatively small ship, only 4 crew members. Only living space was 4 hitchhicker containers, a lab some cupolas (all stuff that reduces stress). the living space itself was about 50 tons, and with roughly 10 tons of supplies I could have lasted almost 30 years. Still, to avoid isru and make a grand tour, I needed a good 20 km/s on the main ship. Which I got by a multiple drop tank design, and it raised the total mass up to 5000 tons. even using nuclears.
  14. king of nowhere's post in How to eject into a resonant orbit? was marked as the answer   
    No, no real formula that I know of - maybe one, but later about this. You just have to calculate, manually, your orbital time.
    The good news is, it's easier than it looks like; i recently learned it, and it worked immediately.
    I made a very simple datasheet to calculate this

    As you can see on the red circle, the two lines of numbers are just iterations, where the same numer is added over and over. In this case the upper line is the orbital period of Eve, and the lower line is the orbital period of my spaceship. So, the first line is just telling me that eve will return to the same position after 261.9 days, and then after 523.8 days, and then after 785.7.... while my spaceship will return to the intercept in 174.6 days, and then the next time in 349, and so on.
    And i just manually look if some of those numbers check. In this case, the datasheet shows that in 523.8 days eve will pass again through the intercept having made 2 orbits, while my spaceship will pass in the same spot at the same time having made 3 orbits, so a 2:3 resonance. But i used a 9:10 on kerbin earlier, and it's not any different.
    If the numbers don't check, i look where the numbers are closer, and I try to refine it. For example, in this case maybe i started with 180 days of orbital period, saw i would be late for a 2:3 resonance, and tried to adjust for a faster orbit. if that was not possible, i could have tried for a 3:4 resonance, and so on. there are more refined ways and more accurate tools, but this one suffices.
    Manuever-node wise, the way to do it is to set up a manuever node (without any actual deltaV used) after the gravity assist. it will tell you the new orbital period. so you try to adjust your flyby so that the new orbital period, shown in the second manuever node, will match what you calculated. You can't see your new orbital time when you adjust the flyby, you have to tinker with the correction manuever blindly and then select the second manuever node and see if the orbital time is right. however, with a bit of trial and error you can do it. and if your new orbit is a few hours shorter or longer than it should be, a correction manuever to fix that is cheap - so long as it's just a few hours.

    This image shows one such manuever planned. You can see the new orbital period, 385 days, in the bottom left corner of the image; it's the 9:10 resonance with kerbin i calculated. you can see the manuever node selected.
     
    Now, i said that there was some formula in addition to all this. Namely, there are 2 other mathematical boundaries.
    The first, and most important, is that you leave your planet after the flyby at the same speed you arrived, only in a different direction. example of why this is important: after my third kerbin flyby, i reached an intercept to eve. i was aiming for moho, and from eve to moho a transfer takes roughly 1000 m/s excess speed (in addition to eve escape). but my trajectory from kerbin had a 600 m/s intercept speed over eve. Guess what? No matter how much i tinkered with the trajectories, i could never intercept moho the way i wanted. I had to provide the additional 400 m/s with a burn at eve periapsis.
    So, if you've ejected from earth at the minimum excess speed, you won't ever be able to reach jupiter with any amount of flybys. you need two planets to bounce against each other, gaining energy at every step. on kerbin you can also use mun, if you include a mun flyby you can leave kerbin at a different speed than you had coming in. but the real moon has too much of an orbital inclination and too slow an orbital time for this to be practical. On the plus side, if you left earth on an inclined orbit, you can use the flyby to change your orbital inclination for free.
     
    second boundary, every planet can give you an assist for a limited amount of deltaV - the closer the pass, the higher the deltaV. if that deltaV is not enough, you have to make multiple passages. For example, kerbin can give you roughly 500 m/s kick, maybe 700. if you are coming from jool, excess speed of 1000 m/s, and you want to go to eve, you can do it - convert your excess speed of 1000 m/s going away from the sun to 1000 m/s going towards the sun.
    But you won't be able to do it in one passage. not even in 2. you have to first lower solar apoapsis, ejecting into a resonant orbit to meet kerbin again, lower apoapsis again, into another resonant orbit, and finally you can leave kerbin with kerbin as your solar apoapsis. because you had to change your speed by 2000 m/s, and kerbin can give at most 700 m/s, so you needed no less than 3 flybys. I can't give you hard numbers, unfortunately. especially not for rss.
     
    I hope I was clear. In addition, I can link you to the mission report where i describe how i went from ike to moho with resonant gravity assists. It took very long, but it was surprisingly cheap, and very rewarding. and my mothership didn't have enough deltaV to do it any other way. It is described in detail, so you may get some additional information.
     
  15. king of nowhere's post in Eve Contract was marked as the answer   
    as far as i understand, it wants your rover to have the "splashed" condition, which requires landing in water. no need to have a biome named "ocean". in fact, no need to get a liquid biome at all; somebody achieved the "splashed" condition on kerbin's desert, because there are a couple oasis
  16. king of nowhere's post in How to do a crewed Duna and/or Eve flyby? was marked as the answer   
    well, of course the mission is possible. you need to get the right gravity assist from duna to get into an eve intercept trajectory.
    now, the basics of gravity assists is that if you pass in front of the planet you decelerate, and if you pass behind the planet you accelerate. so, to get to eve, you want to lower your solar periapsis, you need to decelerate, you definitely want to pass in front of duna. to reach eve at the first orbit, though, requires special planetary alignment, and i'm not sure how much you'd have to wait for a chance like that
  17. king of nowhere's post in Tiny unKerballed probe into LKO? Stability trouble over 25km. was marked as the answer   
    A battery looks big, but it's just 5 kg.
    a parachute, on the other hand, is no less than 100 kg - unless there is some modded lighter version.
    on a probe so small, it may actually be more convenient to mount a more powerful engine and rocket brake.
  18. king of nowhere's post in Tiny unKerballed probe into LKO? Stability trouble over 25km. was marked as the answer   
    yes, SAS won't help if you leave it turned off. or perhaps you have it on, but then the probe goes in shadow, the batteries run out, and sas deactivates.
    Yes, you should add a battery. the basic one is a bit bad for aerodinamics, but there is the stackable circular one that you can put between the body and the nose cone for only 10 kg.
    then the octo does not have the functionality to hold directions. it will keep your probe still, but it will not point to any specific direction. you have to direct it manually. you said your probe was drifting, right? i assume you were trying a prograde burn, started with the prograde indicator there, and then the probe gradually shifted away from the indicator? in this case it's not the probe drifting, it's the prograde direction drifting. as you circle the planet, where is prograde changes. so yeah, you will have to make the manuever by hand holding the direction and compensating for that.
    Finally, i also see in the picture that the probe icon on top is in yellow. which means it has somewhat limited functionality. it's in the sun, so it has power. perhaps it is still hybernated?
  19. king of nowhere's post in Precision landing on bodies with an atmosphere was marked as the answer   
    my way has always been to save and reload until i got there. even then, it's difficult. only with a lot of effort i can even hit the biggest island on laythe.
    but if you don't mind wasting some fuel, there is a shortcut: make a high speed pass in the atmosphere. then, when you approach the target, burn your rockets.
  20. king of nowhere's post in Eve lander keeps sliding sideways until it breaks was marked as the answer   
    both. it''s a glitch, but can be prevented with design
    as far as i can tell, the problem is landing legs. the ship is bouncing on them too hard. the ship works on kerbin, but eve has higher gravity. the ship weight is pressing down hard against the landing legs, causing malfunctions. i have encountered a similar problem.
    possible solutions:
    - try to add landing legs
    - try to tamper with spring values in the landing legs
    - try to use a different model of landing legs (i only had this problem with that specific model)
    if you can find a solution, please tell me which one it was, since i had the same problem myself
  21. king of nowhere's post in Docking Encounter Tips was marked as the answer   
    so, you have your ship you want to reach in orbit.
    you start by sending your new ship in an orbit inside it, touching it on a point. if your target is on a 80x80 orbit, you want to be on a 80x75 orbit.  of course, fix the orbital plane first (there are ways to skip this, and they save a little bit of fuel, but are harder)
    so, the smaller an orbit is, the shorter it takes. the ship in the smaller orbit will slowly gain on the other one. this will let you reach a ship ahead of you - i generally target for this situation when i lauch for a rendez-vous. if instead you are ahead of your target and you need it to catch up, just increase your orbit a bit, still touching your target. in this example, an 80x85 will do.

    here is an example. i am commanding the space station and want to reach the plane. i am a bit ahead of it, so i put myself in a slightly larger orbit, so the plane will reach me in a few orbits.
    keep this difference small, the greater the difference in the orbits, the more fuel you'll have to use to equalize the two vessel's speed

    ok, so here we see the orange marker for the next close encounter. the plane will still be behind me. we set up a manuever node just after the close encounter

    now that we set up the manuever node, the game calculates the closest approach after the node. this means in the next orbit. so in the next orbit the plane will be closer, but still behind us. so we right-click on the manuever node and shift it ahead by one orbit

    now the manuever node is 2 orbits from now, and it says that in the third orbit, the plane will be slightly ahead of us.
    that's just what we want! now we only have to make sure that instead of being ahead of us, it just reaches us perfectly.
    to do so, we must accelerate just a bit, enough to cover those 29 km that the plane will have made past our position.
    and to accelerate, we need to burn retrograde. our orbit gets smaller, and we accelerate and gradually catch up to the plane again, until we have a near perfect encounter

    you don't even need a manuever node; just burn retrograde very slowly, and you'll see the close encounter marker gradually shift.
     
    i hope that was helpful.  the  key is to have the two orbits intersect in one point, and then burn in that point, prograde or retrograde depending on whether you need to go slower or faster.
  22. king of nowhere's post in Editing a craft file to remove fuel? was marked as the answer   
    easy enough. you open the file, there you have a list of parts. parts that can store stuff that can be consumed (fuel, ore, electricity) have a "resource" tab. there you can set your value as you will. under the spoiler you will find such a part, with the relevant resource parts highlighted.
    what's actually difficult is figuring out on which tank you are actually removing resources. it may be more convenient to empty all of them and refill manually those you want filled
     
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