Snark

They do! People do it all the time. You can upload your pic to imgur.com just fine, yes? In that case, to show it here, just do this: go to the page on imgur.com where the image is right-click on the picture and choose "Copy Image Location" paste that URL (should end in .jpg or .png) here That's it! When you paste the URL of the image, the forum will automagically replace it with an in-line image. Like this: (note, this works with any image-hosting site, not just imgur) If your CoM is in the rear, then that's almost certainly your problem right there. It's very difficult to make any craft aerodynamically stable if the CoM is near the rear; that's like trying to throw a badminton birdie backwards. The massive end wants to be in front. So you very probably need to design your craft with the CoM farther forward. Will wait on seeing a picture before trying to offer any advice that's more specific, though.

Hello, @Helmars, and welcome to the forum! Moving this question about gameplay to Gameplay Questions.

Fair 'nuff... but it's quick to register, and if it doesn't get logged into the bug tracker, it's significantly less likely that the team will take a look at it. You're running KSP 1.11.1, yes?

Yeah, that kinda sounds like a bug, all right. Could you log it on their bug tracker, per the above suggestion? (And post a link here, for those of us who'd like to follow along.)

...while also bearing in mind that this is not sufficient-- it's absolutely possible to have an unstable plane whose CoL is behind the CoM. If the CoM is near the rear of the plane, then it's almost certainly going to be unstable, regardless of where the CoL is. @Cloakedwand72, could you please post a pic of your plane? Ideally in the SPH with CoM displayed. (Especially if you could do so with empty tanks, i.e. mimicking the plane's condition on reentry, so we can see where your CoM is when you're not carrying a heavy fuel load.)

What does the F3 dialog say when this happens? And are you running any mods? If so, is this something you can reproduce in stock? If you have found a bug... best thing to do is to report it on the official bug-tracker site (I just now checked, and I couldn't find such a bug already reported): https://bugs.kerbalspaceprogram.com/ ...and once you've done that, could you share a link here for those of us who may be interested to follow along?

If you're open to the idea of using mods, you could use this mod of mine that was designed for precisely this type of scenario.

Could you give us a screenshot? Ideally in the SPH with the CoM display visible. Note that having the CoL behind the CoM does not mean it's necessarily stable. For example, if you've got the CoM close to the back of the vehicle, it'll probably be unstable regardless of where the CoL is. Seeing the craft would make it a lot easier to provide specific advice.

Yes, this exactly. (Or perhaps better to copy it elsewhere rather than moving, so that you still have the original sitting there where Steam can find it and update as need be.)

Hopefully someone more knowledgeable on this topic can correct me if I'm wrong, but... I don't think this is actually possible, given the way KSP is implemented. I believe the way it works is that planets are basically height maps-- meaning, you can give the terrain whatever elevation changes you want, but you can't have overhangs or "ceilings". So, you can't have a solid surface (i.e. ice) that has anything "underneath" it. If you have an ice sheet, fine-- but as far as the game engine is concerned, it's not a "sheet", it's just a flat ice-colored surface that's solid all the way to the core of the planet. If you want to have a water-filled "hole" in it, you can... but it would have to be just be a deep pit with solid vertical sides. Other thant his, AFAICT everything else you describe in your OP sounds technically doable to me. Just wanted to give you a heads-up about this.

@Helvica_Ring_Scientist Looks like it's fixed in 1.11.1?

Because it's like this: "Motor Size & Output" is basically how big and powerful is the motor. In other words, something that they build at the factory, so to speak. Is it a big, heavy powerful motor with lots of wires and magnets? Or something small and weak and lightweight? That's why changing this option affects the weight of the part, and also why it's only in the VAB or SPH. It's not like you can "make the motor bigger" when you're in flight. "Torque Limit" is like the gas pedal in a car. It's a control input. Are you running the motor at full power, or are you only giving it just a little bit of electricity? Basically, it's a power knob that your kerbonauts can adjust in flight, so to speak. I'm sorry, I kinda lost you there... not quite sure what you're getting at, so I'm not sure whether the above explanation is helpful to you or not. If you're asking about setting the "torque limit" while still in the VAB/SPH, then I don't think it's available in stock. I would imagine it wouldn't be too hard to make a mod that would do this, but off the top of my head I don't know of one-- if that's what you're looking for, the Add-on Discussions sub-forum would be the right place to ask.

Moving to Gameplay Questions.

Hello, and welcome to the forums! Moving to Gameplay Questions. Yes. It's that "Motor Size & Output" slider that you show in your screenshot. That sets how much torque the motor has when it's at "full power". The "Force Limit" that you set in flight, always goes from 0% to 100% of the max motor power. So for example, consider these two cases: You set the "Motor Size & Output" to 20% in the VAB, and then in flight you set the Torque Limit to 100%. You set the "Motor Size & Output" to 100% in the VAB, and then in flight you set the Torque Limit to 20%. These two cases would produce the same amount of torque. So, basically, "Motor Size & Output" sets what the maximum is, and then the Torque Limit sets what percentage of the maximum it's using.

Well, first of all... it's actually probably easier to fly the stranded pilot across the 40 km on EVA. Kerbal EVA packs are ridiculously overpowered-- they have like 600 m/s of dV in them. If you just take the stranded pilot EVA, designate the fueled craft as his "target" (so you can see it on the navball), and then just take off by thrusting forward and upward until you've got a forward speed of, say, 100 m/s and a good strong vertical boost, then you can just cruise to the target pretty easily (thrusting upwards as needed to keep you "airborne", and then braking when you get to the destination.) Takes zero fuel, is pretty easy to get there. So, that's what I would do, in such a situation. If you prefer flying the ship, though, it's not too bad. Here's what you'd do: Go into map view and zoom in as close as you can so you get an idea of what bearing from your fueled craft is the stranded craft. i.e. is it to your east? northeast? south? etc. Figure it out as a degree bearing (approximate), since that's what the navball is calibrated in. 0 = north, 90 = east, 180 = south, 270 = west. What's the bearing to the target? Now switch back to flight view. Your craft is sitting on the ground pointed close to straight up, so you should be able to see all the different navball bearings on the navball. Looking at the navball, and bearing in mind the approximate bearing that you figured out in step 1, note which direction that is. If you draw a line from the zenith (straight up) direction to that bearing, which way is it pointing on your screen on the navball? Up, down, left, right? This is the direction you'll need to rotate after liftoff. Take off on full throttle, and instantly after you're off the ground, rotate the ship until you're pointed 45 degrees above horizontal (i.e. your marker is on the 45-degree line of elevation), with your azimuth (i.e. compass bearing) pointing in the general direction of the target. While you're still thrusting, now quickly switch back to map view. You can see your projected trajectory, making a parabolic arc up into the sky and back down again into the ground. As you keep thrusting, that arc will grow, and your projected impact point with the ground will move away from you. It should be moving towards the target, assuming you got your azimuth correct when you took off. Watch until your projected landing spot reaches the target, then cut throttle. You're now en route! Coast until you're approaching your impact landing, then just thrust as needed so that you land instead of going splat. At this point you should be pretty close to your target. Actually doing a precision landing right next to it can take some fine tuning that I haven't gone into, here... but you'll be pretty close, and even if you're a few hundred meters away (or even a kilometer), you're still way closer than you were, and it should be really easy to EVA-fly the stranded pilot to your nearby landed ship. Does this help?

Good luck! Let us know how it turns out?

OK then, sounds like you've got the ship-design angle all figured out. Okay, on to "how do I rescue the poor guy". So, the way you'll rendezvous will have steps like this: Launch rescue craft to LKO, then burn to put it on course to the Mun. (I'll assume you know how to do all that, since you've already done it before.) Make it so that as you approach the Mun, your Pe is just barely inside Jeb's orbit. Basically you want your projected path to be just "kissing" the target craft's orbit, with your Pe barely inside it. You're now on a hyperbolic flyby path of the Mun (since you haven't captured yet). Right at your Pe, set a maneuver node and give it some dV: enough to capture to the Mun, but not enough to match orbits yet. Lower your Ap to something that's still substantially higher than Jeb's orbit. Ideally you'll be coplanar at this point, assuming that you've kept everything equatorial (both the orbit of your rescue craft, and Jeb's orbit). Following description assumes this. If this is not the case-- i.e. if Jeb isn't in an equatorial orbit, but is in an inclined one-- tell us, please? Then you'd have extra steps. So, you should now see markers for "next two encounters" that will give you a sense of how close your craft will pass to Jeb as it orbits around. You've got the right geometry set up, now you need to work on the timing so that they'll be in the same place at the same time. Carefully give some more dV to your maneuver node. This will shrink your orbit, and as you slowly/carefully add , you'll see the closest-approach markers move around. Your goal is to adjust it until the amount-of-separation is at a minimum, i.e. so that the markers for the two ships coincide. Once you've gotten that, you just do the burn. Then coast around until you approach the encounter. When your ship gets within a certain distance of the target (like 50 or 60 km), then your navball will shift to "target-relative" mode. From this point, follow the first few steps from this illustrated guide to docking (only as far as step 3, since you're not actually docking), until you end up parked next to Jeb, fairly close by, at near-zero relative velocity. At that point, you then switch ships (use the [ or ] key), send Jeb EVA, have him collect any science out of the pod, then he lets go and spacewalks over to the rescue craft to get in. Then you just fly home. Ta dah!

Okay, yeah, so, you got this! We'll talk you through it. First, the design of the rescue craft. You need to build something that can get to Mun orbit, pick up Jeb, and bring him home. You have two design strategies you could follow: Piloted Unpiloted A piloted rescue craft would likely be a Mk1 pod with a pilot in it (to fly the craft), with a Mk1 crew cabin attached that's empty at launch (so Jeb has a place to ride). An unpiloted craft would have a probe core and some decent antennas, so it only needs a Mk1 pod (which you launch empty). It flies uncrewed to the pickup, then Jeb's aboard. The former is easier to guarantee that you maintain control (since it doesn't depend on comms at all), but will be somewhat heavier since you're lugging around that crew cabin. The latter can be lighter, but you'll need to ensure battery power and antenna connectivity. Got any preference for one or the other? Not sure what your preferred play style is. Looks like he hasn't gotten that far in the tech tree yet. Probably easiest just to rendezvous, spacewalk Jeb across to the rescue ship, and then just leave the old ship in orbit around the Mun.

Great shots, thanks! So yeah, your best bet's going to be sending a craft to rendezvous with your stranded one, then spacewalk Jeb from the old craft to the new one (bringing along any science you may have aboard). You can totally pull this off (and you'll learn some useful KSP skills in the process). Advice to help you will depend on what you've unlocked in-game, though. Have you upgraded both Mission Control and Tracking Station at least once each? i.e. are you able to make maneuver nodes?

Though, really, just the orbit. He got to Mun orbit before, he can get to Mun orbit again (regardless of game mode and tech tree)-- especially since the rescue won't require going down to the Mun's surface and back, which saves over a km/sec of dV.

There's no way to know-- he could be playing a sandbox game, for all we know. And in any case, if he could build a ship that could get to the Mun, down to the surface, and back to Mun orbit again... then he can certainly build a ship that can just go to Mun orbit to pick up the stranded kerbonaut. It's a question of talking him through how to do a rendezvous, probably. But would be really handy to know what the current orbit looks like.

There are three main reasons why someone might have difficulty getting to orbit-- from your description it's not completely clear which of these you might be running into (possibly more than one): A problem with rocket design (e.g. it doesn't have enough oomph to get to orbit) A problem with the ascent profile during the early part of the burn (e.g. the path you take during the first 20 km or so that you're climbing) A problem with orbital insertion (e.g. what you do as you raise your Ap and then circularize) The folks who have already posted here have some excellent advice about #3, and some on #2, but it's also possible you could have an issue with #1. Could you post a screenshot of what your rocket looks like? Also, what does your early launch profile look like? i.e. what's your flight path during the first 20 km or so? (For example: When the rocket reaches an altitude of 10 km, how fast is it going and what angle from the vertical is it?)

What sort of orbit is he in around the Mun? i.e. what's the Ap and Pe?

Could you post a screenshot of the rover?

Ah. Well, in that case, the answer to the original question, ...is "I have no idea, why don't you try it and see?" Had never heard of that mod before. I have no idea how it works or how it's designed, so therefore no idea to what degree it does or doesn't play nice with MissingHistory. Certainly there's nothing special in MissingHistory to try to specially be compatible that way. So basically, whether it'll be "compatible" or not depends on, 1. what you mean by "compatible", and 2. to what degree that mod is designed to work "in general" rather than, say, addressing certain specific engines.