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king of nowhere

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  1. king of nowhere's post in 800 m/s of dV left for Duna insertion, but maneuvers always use over 1300 m/s of dV was marked as the answer   
    Sorry to say, but your transfer is terrible. Judging from how little the trajectory is deviated by the gravity, it looks like 1-2 km/s of intercept speed.
    and of course you can't aerobrake; if you go too fast, you melt.
    so, learning to make better transfers will both reduce your insertion deltaV, and make it more likely that you could aerobrake.
     
    And the key to a low intercept is that your trajectory must be as similar as possible to that of the target body. the planet is moving very fast. your ship is moving very fast. when you intercept, you have to pay the difference in speed. but think if it was two cars instead. two cars moving at 100 km/h. if they are going in opposite direction, the speed of a frontal crash would be 200 km/h. that would also be the amount of deltaV needed for them to equalize their speed. if they are hitting at 90 degree instead, it means one car has to slow down by 100 km/h in the Y direction, and gain 100 km/h in the X direction; by pitagora's theorem, it's an intercept speed of 142 km/h. but if they are moving in the same direction, they are standing still compared to each other.
    the best way to transfer is called hohmann transfer. here you get an example

    you can see, the transfer orbit is an ellipse having earth(kerbin) on the closer point to the sun, and mars(duna) in the highest point. this way, when you reach duna, both the planet and your ship are moving in the exact same direction. duna is moving faster than you, and you have to compensate for that, but it doesn't take much. instead, if your solar apoapsis would extend way beyond, you're moving across duna's orbit, and you're going to have a horribly high intercept speed. which is your case.
    a transfer window is the time when the planets are aligned so that you can leave kerbin on a hohmann transfer orbit, and reach duna at apoapsis.
    orbital inclination makes things more difficult; for duna you can just make a plane change at a node, but if the difference in inclination is high, a plane change is hellishly expensive (can be as high as 2 km/s for moho) and there can be better strategies. but that's not a concern right now. at the moment, your objective is to get a hohmann transfer right. try one.
     
    another thing to consider is the Oberth effect; it basically means that a prograde/retrograde burn is more efficient if you make it closer to a source of gravity. so going from kerbin to duna is cheaper if you launch from low orbit than if you launch from a higher orbit. And a capture burn is cheaper if you perform it closer to the planet. try to plan the maneuver, you should see that your capture deltaV should lower considerably if you lower your apoapsis from 500 to 50 km. though not enough to salvage the mission, probably, in your case.
    if you have low thrust, and your capture burn lasts several minutes, you're going to get less benefits from oberth effect - because you're performing part of your burn far from the planet. oberth is bigger on bigger planets, so it's important to get close for a capture at duna, and even more at eve or kerbin, while on a minmus intercept it makes very little difference.
  2. king of nowhere's post in DV for LKO -> Pol Surface was marked as the answer   
    well, as you yourself recognize, it depends greatly on the mission profile. if you can get to jool with gravity assists, you can spend as little as 900 m/s to get there - starting with using Mun to get out of kerbin's SoI. Otherwise, a direct mission will cost at least 2100 m/s.
    Once you get to Jool, I recommend to not use the direct injection method suggested by @Superfluous J; that method works well with big moons, where you can get Oberth effect from the moon itself, but not on something as small as Pol. I definitely recommend using Tylo for a gravity assist instead. If you place your gravity assist correctly, you can achieve for free a Jool orbit with an apoapsis touching Pol's orbit and a periapsis somewhere around Vall. From there, it takes roughly 500 m/s to intercept on Pol - a lot less than you could achieve in other ways. And then you need 100 m/s to land on Pol.
    So, 2700 m/s total. Make it 3000 for safety. Could be as little as 1500 m/s by reaching Jool with gravity assists.
    EDIT: Aerobrake at Jool is not a good idea. You may do it with a very good heat shield, but even if you are successful, you end up in a orbit with a low periapsis, so intercept speed on any of the moons will be more expensive. Aerobrake at Laythe is possible, actually it could save some fuel if you can partially aerobrake on Laythe but without getting captured, instead using that to enter a trajectory intercepting Tylo, from where you could get to Bop with a lower intercept speed. but it's extremely difficult to control your trajectory out of an aerobraking passage. And if you use Laythe for a gravity assist to Pol, you will have a higher intercept speed than if you did it from Tylo.
     
  3. king of nowhere's post in DV for LKO -> Pol Surface was marked as the answer   
    well, as you yourself recognize, it depends greatly on the mission profile. if you can get to jool with gravity assists, you can spend as little as 900 m/s to get there - starting with using Mun to get out of kerbin's SoI. Otherwise, a direct mission will cost at least 2100 m/s.
    Once you get to Jool, I recommend to not use the direct injection method suggested by @Superfluous J; that method works well with big moons, where you can get Oberth effect from the moon itself, but not on something as small as Pol. I definitely recommend using Tylo for a gravity assist instead. If you place your gravity assist correctly, you can achieve for free a Jool orbit with an apoapsis touching Pol's orbit and a periapsis somewhere around Vall. From there, it takes roughly 500 m/s to intercept on Pol - a lot less than you could achieve in other ways. And then you need 100 m/s to land on Pol.
    So, 2700 m/s total. Make it 3000 for safety. Could be as little as 1500 m/s by reaching Jool with gravity assists.
    EDIT: Aerobrake at Jool is not a good idea. You may do it with a very good heat shield, but even if you are successful, you end up in a orbit with a low periapsis, so intercept speed on any of the moons will be more expensive. Aerobrake at Laythe is possible, actually it could save some fuel if you can partially aerobrake on Laythe but without getting captured, instead using that to enter a trajectory intercepting Tylo, from where you could get to Bop with a lower intercept speed. but it's extremely difficult to control your trajectory out of an aerobraking passage. And if you use Laythe for a gravity assist to Pol, you will have a higher intercept speed than if you did it from Tylo.
     
  4. king of nowhere's post in DV for LKO -> Pol Surface was marked as the answer   
    well, as you yourself recognize, it depends greatly on the mission profile. if you can get to jool with gravity assists, you can spend as little as 900 m/s to get there - starting with using Mun to get out of kerbin's SoI. Otherwise, a direct mission will cost at least 2100 m/s.
    Once you get to Jool, I recommend to not use the direct injection method suggested by @Superfluous J; that method works well with big moons, where you can get Oberth effect from the moon itself, but not on something as small as Pol. I definitely recommend using Tylo for a gravity assist instead. If you place your gravity assist correctly, you can achieve for free a Jool orbit with an apoapsis touching Pol's orbit and a periapsis somewhere around Vall. From there, it takes roughly 500 m/s to intercept on Pol - a lot less than you could achieve in other ways. And then you need 100 m/s to land on Pol.
    So, 2700 m/s total. Make it 3000 for safety. Could be as little as 1500 m/s by reaching Jool with gravity assists.
    EDIT: Aerobrake at Jool is not a good idea. You may do it with a very good heat shield, but even if you are successful, you end up in a orbit with a low periapsis, so intercept speed on any of the moons will be more expensive. Aerobrake at Laythe is possible, actually it could save some fuel if you can partially aerobrake on Laythe but without getting captured, instead using that to enter a trajectory intercepting Tylo, from where you could get to Bop with a lower intercept speed. but it's extremely difficult to control your trajectory out of an aerobraking passage. And if you use Laythe for a gravity assist to Pol, you will have a higher intercept speed than if you did it from Tylo.
     
  5. king of nowhere's post in are there any good tutorials on gravity assists? was marked as the answer   
    it's not a matter of left or right, but of passing in front or behind a planet. if you pass behind a planet, you are accelerated, while if you pass in front of a planet you are slowed down. since all the planets rotate in the same direction, it translates to left and right
    for a multiple gravity assist, you have to be ejected into an orbit with a duration multiple of the target body - a resonant orbit. that is, if you aim for kerbin and you want to take a second passage, you need to eject into an orbit that lasts exactly 2 years, or 3 years. or 2.5 years, in which case you will meet kerbin 5 years later in a 5:2 resonance. to see how long the new orbit would be, put a maneuver node after the planetary encounter, leave it at 0 m/s; when selecting it, you'll be able to see the orbital time in the lower left corner.
    this is a common misconceptions: a gravity assist will not slow you down compared to the planet. it will change your speed relative to the sun, or you can get one from a moon and change speed relative to its planet. but your speed relative to the celestial body providing the assist is always the same. so you still should enter aligned with the planetary rotation.
    Even with gravity assists, a full grand tour requires more deltaV than a ship can reasonably have. so you have a few options if you don't want to mine fuel:
    1) use lots of drop tanks
    2) use ion engines and lots of xenon
    I'm not aware of any advanced one - the one linked by @Caerfinon is pretty basic and looks like stuff you already know - but, at the cost of looking crass for shipping my own content, I will point out that in my mission reports I do talk extensively of gravity assists with technical details, because I do think a mission report should allow someone else to replicate what you've done.
    So I'll link a few chapters dealing with lots of gravity assists:
    https://forum.kerbalspaceprogram.com/index.php?/topic/203233-lucy-in-the-sky-with-deadly-radiations-3-skys-just-got-a-lot-bigger-kerbalism-opm-grand-tour/&do=findComment&comment=4046683
    this first one is a mission to moho using lots of conjoined gravity assists into resonant orbits to lower deltaV cost.
    https://forum.kerbalspaceprogram.com/index.php?/topic/203233-lucy-in-the-sky-with-deadly-radiations-3-skys-just-got-a-lot-bigger-kerbalism-opm-grand-tour/&do=findComment&comment=4055758
    this is the next chapter, detailing the return trip from moho to the mun using eve
    https://forum.kerbalspaceprogram.com/index.php?/topic/203233-lucy-in-the-sky-with-deadly-radiations-3-skys-just-got-a-lot-bigger-kerbalism-opm-grand-tour/&do=findComment&comment=4068922
    this chapter deals mostly with dwindling life support resources, but subchapter 19.2 uses a jool+tylo gravity assist to reduce speed and set up an encounter with kerbin, and 19.4 details a way to turn that into a low speed encounter with duna a few years later.
    https://forum.kerbalspaceprogram.com/index.php?/topic/208134-lucy-in-the-sky-with-deadly-radiations-4-the-real-sky-this-time/&do=findComment&comment=4139639
    4.2 details going from phobos to venus using an earth flyby, and 4.6 the reverse trip, still using an earth flyby
    https://forum.kerbalspaceprogram.com/index.php?/topic/208134-lucy-in-the-sky-with-deadly-radiations-4-the-real-sky-this-time/&do=findComment&comment=4145720
    this chapter is the trip to mercury, which entails the same amount of gravity assist as the trip to moho i linked earlier
    https://forum.kerbalspaceprogram.com/index.php?/topic/208134-lucy-in-the-sky-with-deadly-radiations-4-the-real-sky-this-time/&do=findComment&comment=4166092
    and this final chapter is my greatest achievement in gravity assists: reaching Io, the innermost moon of jupiter, with limited fuel. It includes 30 gravity assists.
     
    I do believe you can find more informations there than in most guides.
     
  6. king of nowhere's post in Dres contracts was marked as the answer   
    what do you mean by "necessary"?
    if you're arrived to dres, by now you should have unlocked the full tech tree, and have virtually unlimited money, so nothing is really necessary.
    if you are just asking "can I scan that stuff? is there scannable stuff on dres" then the answer is yes. I have never seen this specific rock formation, but i haven't been to dres in several updates; you may also have graphic mods. either way, dres has two scannable objects, so a rover arm will be useful.
    I don't know why you didn't include one already; i see your rover has six of the biggest wheels, totaling 9 tons alone. plus the mk3 cockpit and a bunch of crew pods, that thing must be at least 30 tons. compared to that, the 300 kg of a rover arm make no significant difference, you may as well add one.
  7. 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.
  8. 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
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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.
  14. 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.
  15. 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.
  16. 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
  17. 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.
  18. 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.
  19. 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.
  20. 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.
     
  21. 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
  22. 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
  23. 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.
  24. 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?
  25. 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.
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