DMagic

Wow, fantastic efficiency in all stages of this design. That's what, six parts on that rover? Does it actually stay upright, or do you have to keep moving to keep it stable? About that delta-v to capture at Eeloo, I think the difference is due to where in its orbit you are encountering it. Further away it should take less to get into orbit right? That's why Moho is such a beast to get into orbit around; it's so close to the sun. Also, from your screenshot, the your orbit intersects Eeloo's very far away from your apoapsis. You are going the slowest right at the peak of your orbit, so getting into orbit around another planet at any other time requires a lot more delta-v.

I'm not sure that it's my favorite, I've only been there once, but Pol is really interesting. Its coloration is very different from any other planet/moon, it's got those strange rocks on the surface, and it has really varied terrain. Least favorite: The Mun, maybe. I'm not sure why, but I've never had much interest in going to the Mun. I've landed there a few times, and I have a few satellites in orbit, but all of my more complex or interesting missions have been to other places. Maybe it's because everyone seems to go there first and build bases there, so I've spent a lot more time at Minmus and other planets.

Oh ye of little faith, don't despair so easily. But I'm getting ahead of myself. Let's start with my second attempt at an Ike landing. I like this design a lot, but it too has problems. A single xenon tank is just not enough to do anything with 8 ion engines, and the in-game description of the ion engine is wrong. It doesn't use 12 energy/sec, it uses 14.5, that's a big difference when every little bit of mass counts. So this mission also ended in failure. So with those issues in mind I redesigned my lander again. This time I have just 5 ion engines, but 3 xenon tanks, 2 of which will be dropped during the final descent stage. You can see the 2 extra xenon tanks hanging below the central engine on the right here. And with 20 OX-4B's and 50 OX-STAT's I should have enough power to run all 5 engines at max (the decrease in solar panel efficiency is very slight at Duna orbit, about 1.95 energy/sec instead of 2 for the 4B's, but I still took that into account ). And this is my strategy for landing. The most fuel efficient way is, I think, to come in at a shallow angle and bring your horizontal velocity to 0 around the same time you land. That obviously won't work here, I need to keep the solar panels at as close to an ideal orientation as possible. Which means landing with the sun directly overhead. To do this I have to bring my horizontal velocity down to near 0 m/s at a very high altitude, then gradually drop straight down, allowing me to come in at near full throttle. I started at an orbit around 70km above the surface and brought my horizontal velocity down, all the while keeping my vertical velocity around 50 m/s. Then I gradually reduced my vertical velocity as I dropped straight down. This is horrendously fuel inefficient, but that's why I have 2 extra tanks. At around 20km Ike's gravity becomes too powerful for 4 ion engines to counter. So I made sure that my main xenon tank was topped off and dropped the other 2, taking the mechjeb unit with them. You can see all 5 engines now activated as I continue my slow descent. Arrgghh!!! Of course I had to land on a hill, bounce off, and break one of my landing legs. And things only went, um, downhill from here. Now back out of the simulator (upside down upon loading, of course) I'll try for real this time. I gave myself a little by of horizontal velocity in the hope that I would come down somewhere a little flatter and continued down the same as before. Made it. This time I came down in a flat area, and slow enough not to bounce. I'll try out Bop and Pol next. The decreased efficiency of the solar panels at that distance from the sun should make things interesting. But I think those will be the only other possibilities. The Mun seems almost doable, the engines have a high enough TWR for it, but I can't figure out a way to actually power them without adding too much mass. Even using the Kosmos solar panels, which give much higher energy/ton don't work because they are too big to fit anywhere.

I like that lander design. Is that just a set of beams with struts between them?

I have read that same tip many have referred to about putting a control point close to the CoM (it's on the wiki somewhere, I think). I tried this once by putting a probe core above the first stage fuel tank, but it didn't seem to make much of a difference for me. The rocket I built for this way really unstable, maybe using something that's not so inherently wobbly might produce better results. My solution to the problem is just not to use ASAS units. I usually let mechjeb take care of liftoff, which seems to me at least, to do a better job of controlling wobble. But even when I don't use mechjeb, I just manually keep it centered. And disable all but the center engine's gimbal, sometimes even that can be disabled if winglets give you enough control.

I decided the other day that LV-909's and Rockomax 24-77's, even LV-1's, are the coward's engines for landers. Having figured this out I started designing landers using only ion engines in an attempt to land as many places as possible. I may end up with only a few successes, but it's worth it to make the effort. I started easy and went for Minmus. The only mods here are parts from KW, and Mechjeb for the transfer stages of the later crafts. This little booster was enough to get the lander, inside the fairings now, into LKO. I used the ion engines to get to from LKO to Minmus orbit. It didn't really take that long, I just made 3 or 4 consecutive burns (or discharges, maybe?) at Kerbin periapsis. The probe itself is made up of 3 ion engines, 1 xenon tank, 3 small landing legs, 2 gigantor solar panels, and a few small batteries, all of the other structural elements were covered with the small, OX-STAT panels. The initial approach was easy enough, I juts had to make sure I kept in the sun the whole time. And success, the first mission went pretty well. I didn't quite have enough power to run all 3 engines at maximum, but I had enough thrust to land. Having never been to Gilly I decided to head there next. This little baby got my Eve orbital transfer stage up to LKO. And I never realized that docking clamps could be angled like that, I kind of like the way that looks. Fairings are awesome... Given Gilly's small size and proximity to the sun, I made this probe much simpler than the last one. It's made up of just 2 ion engines, a single xenon tank, 4 OX-4B panels, and a few OX-STAT panels. With the transfer stage I plotted a course to Eve. After a very high altitude encounter with Eve I set up an encounter with Gilly and jettisoned the transfer stage. The approach went well enough, Gilly has a ridiculously small gravity well. Now come on, that was just too easy. I think I could have done that with a single ion engine at half power. For the next mission I decided on a tougher target, also one that I've never been to, Ike. I needed a slightly bigger rocket this time for the larger probe. And after getting into orbit around Duna and dipping into the atmosphere to slow down a bit I set up an Ike encounter. This moon is huge in relation to its planet. The probe is a bit bigger this time, it has 7 ion engines, 3 gigantor panels, 3 OX-4B's and a number of OX-STAT's, still just a single xenon tank. The capture and approach to Ike went well enough. But this one never really stood a chance. Those gigantor panels are juts too heavy for how much power they give, and even then they weren't enough to fully power all 7 engines. Stay tuned for more as I try again with Ion Ike Lander Part Deux. Here's a small preview of my new probe lander.

You can also rename your station by right clicking on any of the probe cores. You can also change it so that it appears as a station on the map, not a probe. And about resources being shared, electricity, monopropellant, and I think xenon, will be shared by any part of the station, regardless of how they are connected. Fuel won't be automatically shared between tanks, but you can right-click on one tank and alt-right-click on another and manually share fuel.

Another thing to keep in mind, is that these kinds of physics freak-outs tend to get worse as you add more parts. Try to be as stingy as possible with total part count. Not just to keep performance from dropping too much, but also to avoid some of these weird things.

I like the way this looks (those ramps are a great idea). Usually when you get weird kicks or explosions when the physics starts it means that something is not aligned right. I think usually something is getting forced into the ground so it tends to get bounced out. You have to be very careful to get everything lined up right or this can happen. It might also have to do with the way that everything is resting on the ground. I've never done it this way, I always have everything on legs. Maybe find a way to extend those ramps a little and just leave the landing gear extended. I put up this lesson about testing these things a while ago, it might help a little. http://forum.kerbalspaceprogram.com/showthread.php/27668-Tricks-hints-and-important-lessons?p=340578#post340578

Heat in a vacuum is dissipated by emission of IR radiation, called radiative cooling. It's not as effective as the convection cooling you get in the atmosphere. You can how big the radiators have to be in pictures of the ISS, they are the big flat protrusion coming out from many different sides of the station, the ones that aren't solar panels. A dense atmosphere would be great, but only if the actual temperature was low. If the atmospheric temperature on the surface was very high then I would think an RTG would be less effective. As was mentioned above, the core of the RTG would still be hotter than the surrounding atmosphere, but the relative difference in temperature seems like it would be less. Instead of, say, a 500K core and 275K heatsink, you might have a 700K core and a 475K heatsink. The difference is the same, but the relative increase of the core over the heatsink is less (an 82% increase vs. a 47% increase). Does anyone know if this is right? or if it makes sense? And would that difference in relative temperature differential affect the efficiency of the generator? Now I've got myself confused...

For me, chase view was the key to making docking consistently easy. I could do it before I started always using chase view, but it was always tricky because I ended up moving in the wrong direction at some critical point. With chase view I never have to guess, and I never forget, which direction is which. I use a sort-of awkward, crossed-hands method when docking. My right hand always controls the 6 translational movement keys, and my left hand alternates between activating/deactivating RCS for rotational movement, and using the arrow keys to check on my X and Y axis alignment of the docking ports (for some reason I never liked using docking mode instead of staging mode). And even when you have the camera rotated to the side it's easy to keep track of which direction you need to move.

A good idea is to set up the docking port with an action group (I always put both 'undock' and 'decouple' in the same group, I've never been sure of the difference), that way you can do this more like staging and not have to deal with trying to click on a sometimes partially hidden docking port. Be careful if you use any kind of delta-v calculator though. This will screw up the values it gives, because it doesn't know when, or if, the docking port will be decoupled.

There is nothing inherently unstable about 6 fold symmetry. But if you are having stability problems after dropping 4 of the 6 outer boosters that could mean that your last pair of boosters needs to be better stabilized. Do you put struts between the boosters, or do you put struts between the boosters and the central stage, or do you do both? I've had problems before with the last pair of boosters becoming unstable because all of the outer boosters stabilized each other, so the last pair had very little to hold it in place and needed much more strutting than the other boosters. Or is your rocket actually becoming unbalanced? Is the fuel load somehow different on one side than the other? That would be a different problem, and most likely an issue of fuel flow, as there is no reason that fuel should become unbalanced on 6 or 8 fold symmetry.

The exact coordinates are just cut off from this image, so you can see the general area without the exact location. The probe is over the area on approach.

There is a mod that perfectly addresses this issue. http://kerbalspaceprogram.com/haystack/ It's very simple, it just allows you to either target or control any other craft, even debris, without clicking fifty times on it, or getting lost in all the debris in the way. It doesn't require any changes to your crafts, so it can be used by already existing ships.

I like the 3 ion engine design. I came up with a similar one for my Minmus lander the other day. Which worked out pretty well. And just a single xenon tank was all it took to get from LKO to the surface of Minmus. I think you may be overdoing it a bit. I got a probe into Laythe orbit using just this. The fairings add a lot of mass to the top, so without those an even smaller launcher would do. This is what it took to go from LKO to Jool and Laythe. I think the trick is to find out the smallest thing you to actually need to get into orbit. When you're just sending a small probe it doesn't take much to get just about anywhere in the solar system, except maybe Moho or Eeloo.

There are a lot of these delta-v charts floating around. For Jool and Kerbin though, you can aerobrake, significantly reducing the delta-v necessary to get into orbit around both planets. It takes about 2000 m/s to get from Kerbin to Jool, and maybe 3000 or so m/s to get back. Obviously more if you want to do anything else while there.

Go light with the probes. For 2 or 3 ton payloads you don't need much to get to Eve. And ion engines work great for orbital probes around Eve because the solar panels are so much more efficient (I think around 5/sec instead of 2/sec that you get around Kerbin).

The lander crews plot their return trajectories and burn for a capture at Laythe orbit. Here the orbits of three landers are plotted for their return to Laythe. And one by one they re-dock to the Endurance. Everything's a little smaller than the last time they wore docked together. During the mission it became apparent that there would not be enough fuel for the return to Kerbin. Even after jettisoning some of the dead mass they would come up about 500 m/s of delta-v short of what is necessary for return. With that in mind a refueler mission was launched. The refueler's mission plan called for landing at the Laythe base. Things didn't quite go according to plan however. The crew overshot the base by about 20km and came in a little too fast. Everyone survived alright though, if a bit irradiated. And they can make the trip to Laythe base on foot. With sufficient fuel the trip back to Kerbin begins. The first burn sets up an escape from Laythe orbit back down to a lower orbit around Jool. Endurance burns for home around Jool, and with a small correction burn later on, plots a course for an encounter with Kerbin. Tragedy struck as they passed the orbits of Jool's outer moons. Bop lander Mission Specialist Neweny Kerman, who had been restrained ever since the ill-fated Bop landing, broke free and exited the ship. As the crew looked on helplessly he used his EVA pack to return to Bop, apparently not realizing that he could never overcome his current orbital velocity, taking him outside of the Jool system. He could be heard over the radio excitedly shouting that he was "coming home..." Radio contact was soon lost, his EVA transponder shows him on an elliptical orbit around the sun, though perhaps someday he will end up back on Bop. While the Endurance makes its return trip from Jool, the crew return vehicle is launched. It will await the crew in orbit and return to KSC. After a long trip back the crew finally make it to Kerbin orbit, ready to return to the surface. Just over 3500 m/s of delta-v was required for the return, from Laythe orbit, to Jool, and back to Kerbin. They meet the crew return vehicle in orbit, transferring all but the Endurance pilot, and releasing the landers to burn up in Kerbin's atmosphere. While the crew returns to the surface, pilot Edley Kerman takes the Endurance back to Minmus orbit. There he docks at the Minmus orbital refueling station, ready for another mission. The crew return vehicle begins its descent, approaching KSC from the west and gently setting down just past the launch pad. Home at last. The crew exit the return vehicle and set foot back on Kerbin after a successful mission to all of Jool's moons. That was fun. It was 10 launches, for a total of 11 probes, 2 rovers, 4 landers, 1 refueler, 1 crew return vehicle, and 1 carrier, 20 spacecraft in all. It took a lot of planning, and a few screw ups, but it worked pretty well in the end.

No love for the Joolian moons I see. Tylo might be nice to have a good map of. It can be tough to land and take off from, so it might help to know where the high, flat areas are. Bop and Pol could be interesting because of how absurdly uneven they are. Great work though, these are really well done. Now I'll have to go check out this mysterious, fourth anomaly you've shown on Duna.

The crew of the Tylo lander, having identified a landing site, begin their descent to the surface. Tylo is the heaviest moon in the solar system and has no atmosphere, requiring over 3000 m/s for landing and ascent. After a rather harrowing initial descent, the crew bring the ship in for a relatively soft landing. Soft, but not quite soft enough. The lander came down intact, there was a little bit of worrisome flexing of the radial fuel tanks, but it turned out okay. The rover didn't come through so well though, it lost a few wheels and its main solar array. Thankfully Mission Commander Kenzer Kerman is able to repair the damaged wheels, and the auxiliary solar panels provide enough power to run the rover. The crew poses for a picture. The landing was a little off target, so the rover sets out to investigate the anomaly detected nearby. From the ground, nothing out of the ordinary is discovered. However, the orbital Sat Map probe acquired this image from above. Opinions remain divided as to what, exactly, this means. Mission Specialist Neweny Kerman maintains that "those commie jokers must have got here first." After a successful EVA on the surface of Tylo the crew prepares to leave. Through some careful fuel management, and tricky ascent maneuvers, the crew is a able to successfully regain orbit around Tylo. After starting their descent with a 65 ton vehicle, they are left in orbit with just under 6 tons of total mass. Meanwhile, the crew of the Vall lander, having identified an anomaly in the southern region of the moon, release the probe lander. Initially, nothing unusual is observed, however, as the probe approaches the anomaly, its sensitive cameras pick up an intense emission of dangerous, short-wave UV radiation. The brightness of the anomaly prevents the probe from capturing a clear image. The crew decide to land a safe distance away from the anomaly. The crew step out into the fading light to prepare the rover for its trip and study the surrounding area. Using the rover's more sophisticated cameras, the intense UV radiation can be filtered out, allowing for a clear view of the anomaly. After approaching the area, this strange, and most certainly unnatural formation is observed. More disturbingly, the probe lander has inexplicably moved several kilometers away from its initial landing site. The lander was low on fuel when it set down, how it was moved so far remains unknown. These images of the structure are transmitted from the rover to the crew. The objects are seemingly inert, the crew however, reports an increasingly foreboding sense of dread. They take one last look towards the structure before climbing back into the lander for take off, eager to be away from the planet's surface. They blast off from the surface, separating the radial tanks, leaving only the main engine to carry them away. When passing over the anomaly the crew can clearly see how far apart the rover, still at the structure, and the probe have become. Rather than ponder how this could happen they turn away to prepare for the final orbital maneuvers as Jool rises over the surface, with Laythe hanging in the sky nearby. Next, the final phase of the mission begins, as the landers return to the Endurance in Laythe orbit and prepare for the trip back to Kerbin.

I put up this a while ago about building and testing base components to make sure that the docking ports and landing legs all line up right. http://forum.kerbalspaceprogram.com/showthread.php/27668-Tricks-hints-and-important-lessons?p=340578&viewfull=1#post340578

Here's another one to ponder.

Who says ion engines are only for satellites and course corrections? A single xenon tank and 3 engines are good enough for Minmus.

I like this design, it's sort of the opposite of my Tylo lander. The rover rode in below the nuclear engine, which I only needed for the ascent.