king of nowhere

i went to test a rocket to see if it could land on vall, and i just caught a jool eclypse

no, it has not. aerospike has by far the best Isp at eve sea level. the problem is the low TWR. you need a crapton of darts to get off of eve, so the weight of the extra engines more than compensates for the fuel saving. not to mention the aerodinamic problems caused by so many engines. personally, i like it for ssto planes, they can get by with a low twr and the dart works better in vacuum than other ssto engines.

I am mightily annoyed that all the liquid fuel fuselages are Mk 2 and 3, with shapes meant for airplanes. The nuclear engine is real. I want to make a large rocket with nuclear propulsion, i must use a plane fuselage. The only rocket-friendly piece of liquid fuel tank is the 1.25 m part, which is mostly pointless because nuclear engines only make sense on large rockets I'm posting this because i'm making a 2.5 m rocket, but i have to slip in a mk 3 fuselage, with one adapter in front and another behind. horrible. I'll try to put a structural tube and some mk 1 fuselage clipped inside. i'm sure someone fixed it with a mod, but that would be just one more reason to make it official

you know what, guys, after some more extensive testing i realize the plane is perfect as it is, for my purpose. it is supposed to grab science from laythe in every biome, both on the ground (well, water) and flying over it. this means making a lot of distance over the sea, while still keeping enough fuel to orbit. so my choice of propellers is the correct one. at this point, i must be able to land on water. that, i discovered, can be done even with the new version, it's just a matter of figuring out the technique. i was trying to hit the water as slowly as possible and absorb the impact with the wings, which have a decent impact tolerance; this worked with the lighter model, not with this. but then i discovered that if i enter water very carefully touching only with the wheels, those wheels will slow the plane enough to safely enter with the fuselage too, and i can do it at 70 m/s reliably. i've done it 5 times in a row without crashing, and while i'll still want to save the game before landing, it's a fairly safe manuever. taking off from water is not strictly necessary, but it is highly desirable. i can use my propellers to move around on the water surface and pretend i'm a boat, but i'm limited to around 70 m/s top speed. I can go above 200 m/s in the air, it's gonna make things much faster. And to take off from water, a rear CoM is desirable; it helps me tilt the plane upwards for take off. i tried to move the CoM forward by moving the big fuel tank in front of the command pod, and i discovered that I couldn't take off anymore; when i tried to tilt the tip up, the back of the plane would sink in the water, slowing me down. I also need the huge elevons, to help me get off the water. I tried to add a third pair of wings to improve manueverability at low speed, but they didn't work as well, and they apparently created all sorts of issues. plus they pushed the center of mass way too forward. So I'm basically going with my first model, just with 2 tail fins and the elevons closer to the center. Your input was useful, though. it made me realize that while I could make this plane fly better, I could only do it by sacrificing something else. So there are no engineering mistakes in my design, only trade-offs. Propellers are better. laythe has way too little land to make isru reliably (unless i can mine ore from water? i never tried), and anyway i realized i don't need it. i land on laythe, move around with propellers (fueled by 8 RTG), then i use the fuel only to go back in orbit. I will have a mother ship waiting me, and it will have isru capacity from the smaller moons. not that i will actually need a refueling, since for the other moons i will use a rover. the mission actually has another part earlier, where i dip inside jool atmosphere enough to reach the low atmosphere, do science there, and start again. for this, i coupled this plane with another, bigger thing that will brake during descent (thanks to an inflatable thermal shield used as a parachute, i already tested the concept) and will then propel me in orbit again. this plane then will be the last stage, the one reaching jool orbit. there it will couple again with the main ship to get refueled and explore laythe. my choice of engine works for jool ascent too. the final version i picked and the jool ascent stages. the jool ascent is a pretty poor flyer, but it does its job, and since i intend to only use it once - and it has two vectors to help stability - then it's fine

i reduced the maximum angle to 20 degrees already, because i know the highest deflection level is very inefficient. i didn't want to do all the way down to 15, though, in case i needed some harsh manuever. you are right that the elevons were oversized, in fact i distinctly remember swapping out those bigS for something smaller already in the past. probably i messed up with saving games and i got stuck with the old oversized elevons without realizing. wrong. of course if i pull all up suddenly it will capsize, but moderate deviations (say, up to 10 degrees away from prograde even in the worst aerodinamic conditions) are handled just fine. huh? by making the elevons flat, it pulls the CoL forward, not back increasing the vertical tail instead worked, how would I reduce the amount of area in front of the CoM? All i have there is part of the wings, and I can't exactly move the wings around without messing with the CoL... anyway, i implemented the changes suggested: I swapped out the big elevons for smaller ones and i put them closer to the body, and i swapped out the single vertical fin for two of them. It is, indeed, somewat more stable. I am able to manuever around and then find again a trajectory that won't require constant correction. though that's not always easy, sometimes i point prograde and leave the controls and it keeps flying straight, and sometimes the nose starts going down and i have to manually correct until i find a new stability. So my original doubt "why, when i stop touching the controls, sometimes it keeps flying perfectly straight and sometimes it will not?" is still without answer. i guess it would depend on complex aerodinamic parameters determined by the exact trajectory and pressure Since I was there, i also attached the lateral tanks to the main body. EDIT: what the....? i went back to trying some water landing, and i'm finding out it doesn't fly well anymore. I didn't touch anything since saving the plane after it did fly well... and i can't find stability anymore. and suddenly i have no roll-pitch control it's like the game wants me to revert all the changes i made. but why was it flying correctly the first time i tried them, only to fail the second? EDIT 2: I figured out why i needed the big elevons: it's to land on water. water landing requires careful manuevering at low speed; smaller elevons are more effective at high speed, but they're no good if i can't land. generally speaking, this plane's major goal is exploring laythe, and I can now recognize that some of the things I did that were a bit less effective for flying were meant to improve water landing survivability EDIT 3: i am unable to land on water anymore. to check if it was the new changes, i tried with an old model, and i discovered i also can't land on water anymore. maybe i checked water landing before adding extra fuel tanks. or maybe the game is inconsistent again. anyway, while i was piloting the old plane, i found it behaved well too; i could find stable trajectories easily enough. all things considered, the only improvement is the double fin tail. anyway, i need to alter the project to land on water again. possibly without screwing up flying and going to orbit while at it

here it is. yes, the CoM is a bit back, which is unavoidable when the heaviest parts are the nerv engine, which must go on the back, and the wings, which must generate lift behind the CoM and so must be put fairly backwards themselves. still, I remark that this thing flies pretty well, as long as i never touch the control since leaving the runway. regarding autostrutting, i did indeed autostrut everything I considered also adding manual struts, especially for the lateral tanks. they would probably be a bit more stable, and they would definitely be more stable if i attached them to the central body instead of the wings. but i like the shape now, and in all my simulations it has never been a problem

i would never try to make a steep turn above 10 m/s on a low gravity, even with a rover i consider stable. my rover stops at around 40 m/s, and at that speed i would never try to turn except by the smallest possible increments. and it would take a huge amount of time braking. it's normal. it's how physics work.

yes, i know the basics. and i wouldn't say it's exactly "having difficulties". it flies fairly well, it has ssto capacity, it can go cruise around on propeller power alone and can even take off from water, all on propellers. I just would like to understand why it has that strange behavior i already asked regarding this plane for a problem on the ground (which was fixed), and the pictures are there. i made some changes since that model; i swapped out the liquid fuel tanks with rocket fuel, and i added some extra tanks under the wings, and i added two aerospikes, because i realized going to orbit on a nerv alone was too ambitious. and since the plane was much heavier i added another couple of propellers, and a few more rtg inside the cargo bays to support it. but it makes no difference. it always does the same, sometimes starting perfectly, but losing stability as soon as i try to manuever, to never recover it

200 m/s is 700 km/h, or 400 mph. is it really surprising that at such speed the car is unstable, and that you cannot control it? it's already a wonder you don't break your wheels. I don't think there's any realistic way, short of glitch exploitation, to keep anything stable that fast.

for "explanation" I mean "why that happens". and it has to do with kinetic energy being distributed differently between the ship and exhaust. And that's rather complex, especially if we want to dig into the calculations. Just stating the principle is pretty straightforward, though, i'll give you that

i noticed that sometimes, when i launch a plane and all goes well, the plane will keep the orientation with just SAS set on hold attitude. it will stay perfectly still, without any input, until i touch the controls. or until it stalls for flying too high. other times i need to touch the controls just a little bit. and then there is no way whatsoever to get the same stability. hold attitude, hold prograde, all will result in the tip of the plane going down within a few seconds. hold prograde is especially bad, because the manuevers it does to try and compensate deviations are actually causing greater deviations. it's almost like i'm flying two different planes, one perfectly stable, one not. or perhaps in one case it is like having physical facilitation on. and in the second case flying is much more annoying, as i need to check the controls every time, and also less efficient, because i can't keep pointing the right direction and will face drag. and i noticed this with different planes. anyone can explain why? and if there is a way to reproduce the stability?

to expand, oberth effect has quite a complex explanation, but the overall result is that a prograde/retrograde burn works better the deeper you are into a gravity well. you can experiment this in kerbin orbit; start in a low circular orbit, then make a big periapsis raise, say by 500 m/s. then on apoapsis circularize, and keep track of the expence. it will be more than 500 m/s, because you'll be farther from kerbin and your burn will be less efficient. as you already discovered, when you are on minmus the most optimal trajectory to go far is to fall back on kerbin, and make the big burn at periapsis, to get advantage of oberth effect. as for aerobraking on laythe, you are better off using a gravity assist from it to get into jool orbit.

this is very useful... or at least, it would be very useful if i figured out how to get good information out of it. unfortunately, i could not find ways to get a good drag report. or something to help me optimize drag. that's because most of my drag comes from the wings, and that's good drag, and i can't separate good drag from bad drag. as for the drag of the main body, i only see some reddish parts for those most draggy. as those are generally the wings, there is no big surprise there. also, trying to use the tool on anything more complicated than basic shapes causes the thing to malfunction, sometimes ksp crashes abruptly. It also does not seem to work for anything with propellers. any tip for dealing with those issues?

didn't knew i was supposed to

it worked, thanks

i tried to use silly contracts of testing stuff on the launchpad or in low flights. all was going well. i had reached 20k funds. then a bug struck. i took on a contract, and it was declared failed immediately. i'm not sure what happened exactly that caused me to lose it, anyway i lost all my money. I'm sure this would be a case where reloading is justified. but i wasn't expecting it, so i have no save to produce

i doubt 50 is possible. you still need to spend money on fuel. what you ask would require sending one ton to orbit with 200 kg of fuel ok, it would be technically possible if you start with empty tanks, fill them with isru on the launchpad, and then you launch the rocket. but it kinda defies the purpose of it

I already have a decent experience running spaceplanes, so i was completely baffled when my latest attempt, which is a fairly simple design, failed. It pulls to the right, and as it accelerates it tend to go in circles, eventually capsizing. and i can't figure out why that is. the plane is symmetric, i even tried to remove the rover arm (the only part i see that may be causing the problem) but no difference. i assumed something was wrong with the propellers, but i tried to shut them down and close the cargo bay, and put a rapier engine at the back to give a uniform push, but still it pulls to the right, so it's not the propellers. I'm baffled

the constraints encourage creativity and economy of design. being unable to reload doesn't, have anything to do with it. in fact, being unable to reload actively discourages creativity, because i must stick to proven, tried-and-true designs and mission profiles, for i cannot risk a failure. Ok. I think I see the problem. We have very different concepts of fun. I don't like survival, and I don't like grinding. Striving to do something hard is fun. Something that I can get right 90% of times is too easy. Striving to practice that easy thing so that I can do it right 100% of times instead of just 90% is not fun for me. It is a chore. Doing something easy, many times, but you have to get it right every time, is a good description for most jobs. And 90% success is still way too low for a career. Furthermore, assume i have this challenge running for weeks, dozens and dozens of hours of gameplay.... and near the end i misclick something and lose it all. how is that fun? how could i relax and enjoy the game when i'm under this constant pressure that the slightest mistake would ruin weeks of careful work? It's just not my cup of tea. I need things to be hard enough that I have a real chance of failing, and this only works if I can afford to fail. that roller is a brilliant idea. I was wondering how to collect science from the ksc without having rover wheels available, and this is a brilliant solution. I'm going to copy it

my problem is, i can't take not reloading. this is a game and i will always seek to push limits. safety requires triple-checking everything, never doing anything risky. it's boring. it's good for real life, where you most definitely can't reload, you have a single game that can last up to a century, and you don't want to cut it short. but i can't game this way. and so i have the occasional accident. if i wasn't allowed to reload, i wouldn't pass even at the easiest level. on the other hand, i am reasonably confident that, if i could reload, i could succeed at the hardest level. trying at an easier level when i am allowed to reload would be too easy for everything else. maybe i will try to check if it is feasible to just get science from policies. otherwise, i may just give up on the challenge.

i was always able to do a full aerocapture on duna without any kind of ablator, without ever coming even close to taking damage. including an intercept from dres with a relatively high speed. duna is surprisingly forgiving in that regard. kerbin, not so much. you'll definitely need the heat shield for return aerocapture.

don't strut boosters to each other, it creates problems. strut boosters to the main body of the ship. and it appears you are using 3 rockets strapped together in the middle, strut them tightly. it would be better to have one single rocket with a bigger payload fairing containing all three satellites, clipping must be terrible; but maybe you don't have the technology unlocked do you have multiple probe cores in your satellites? because i can't see one. if there is indeed a probe core on each one of the three, then i have no idea. stuff is generally marked as junk if you can't control it.

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

well, depends on how elaborate the rover is. yes, i've done some landers with wheels that were barely capable of reaching the closer surface feature to get some extra science before leaving again. cheap stuff, generally. But I've also done this it's one of my finest creations. its CoM is low and it is quite stable to drive; I can cruise around Mun at around 30 m/s without crashing too often. while the landing struts make an armor that keeps me alive when i crash at that speed. and it can visit most planets on its own, with ISRU capacity. then again, it's also not exactly a rover, multipurpose vehicle would be a better term. but the point is, you can fit rockets on a rover and do a good job with it. it's not easy to make something that performs well both as rover and as spaceship, but making a sky crane is also not trivial. I see and raise. I've landed a propeller-assisted spaceplane on water and called it a boat hey, it worked!

so, i thought the major problem would be low science, but it isn't even that. it's not being able to reload. within a few hours, i already accidentally killed both my pilots. now, i could circumvent the ban on reloading games. the game still lets you save, it just doesn't let you reload. but all you have to do is delete the "persistent" save and rename your quicksave as "persistent". But i feel that would disqualify me from the achievement, wouldn't it?