DMagic

Now that the station is complete the first order of business is to get some more fuel out to Moho so that the tugs can make it back. A refueler was launched on my 50 ton lifter and sent on its way to Moho. I figured out a different way to do this launch. Instead of putting off the inclination change until I was in solar orbit, I launched into a 20o inclination around Kerbin. Then I waited until I was near the descending node with Moho for the transit. Because I was burning retrograde I left Kerbin's orbit with a descending trajectory. My final orbit around the sun was only off from Moho's by about 1o, so I was easily able to set up an encounter without any further inclination change. While the refueler was on its way the Moho Orbital crew started working to identify the final base landing site. The next probe lander was launched near the south pole. It landed in a slightly more rugged, but still boring area. This crater near the north pole looked like an interesting place to set down, seen here from orbit. So the last probe lander was released and set down near the southern rim of the crater. Next the probe rover was released to further study this crater. You can see the detachable lander system here as the probe approaches the norther region of the crater. This area, just underneath a steep, long ridge could be a good base site. There is a good amount of flat ground and it should be mostly protected from intense direct sunlight. Meanwhile, the refueler has arrived at Moho orbit. My strategy worked out pretty well. A total of just over 8800 m/s of delta-v was used from the surface of Kerbin to a stable orbit around Moho and a rendezvous with the station. After docking to refuel, the tugs were released and set to return home. The fuel tug was able to bring about 1500 units of fuel, with about a third of that remaining at the station. I waited for a launch window near a node with Kerbin and sent both tugs back home. Only a single burn was necessary, using about 2000 m/s for each tug. After aerobraking at Kerbin both tugs made it back with plenty of fuel to spare. Once they get back to Minmus Orbital they will ferry the next station to Moho. We'll carry on with the launch of the next station, its journey to Moho and assembly there.

Sometimes you will need the gimbaling once you start turning. I assign the gimbal toggle to an action group for the booster engines, then disable them on launch. But sometimes I have to reactivate them once I start turning, though by that point I usually only have two boosters left so the overall stability of the rocket isn't affected so much.

Most of my designs use KW Rocketry for fuel tanks, engines, and fairings. Kosmos is used for the station components, the big grey parts and the trusses. It hasn't been updated for 0.2 though, so you have to add "scale = 1" to all of the parts in the .cfg file or else the connection nodes will be screwed up. A few parts are from KSPX, the big nuclear engine and a few small fuel tanks. I also use Sat Map, Quantum struts, nodeselect and Mechjeb. I've been playing around with a few other mods that I'll get to later, too. I'll put up craft files later on when I have most, or all of them, ready.

Carrying on, we have the launch of the remaining Moho station components. Two solar panel truss sections were launched on my 10 ton lifter. And the two habitation sections were launched on the 30 ton lifter with Bill and Shepbro Kerman at the controls. After four closely spaced launches (Kerbals excel at clearing off debris and preparing for another launch) all the components are set on a course for Minmus. While those were on the way, the main station section departed from Minmus Orbital and moved into a 60km holding orbit over Minmus. Some careful docking was required to get everything onto the Talaria tug. One of the solar truss sections arrived first and was docked to the large clamp adapter left behind by the Hermes tug. The hab sections were then maneuvered into place at the front of the tug. Those radial docking ports look like they might attach, but they don't, they are meant for the landers, which will be coming along later. Once everything is in place Bill makes use of the quantum whatever field to stabilize all of the components for transit. With the tug completed they leave Minmus Orbital and move to join the Hermes tug at a 60km orbit. Now this is where the fun part begins. Normally the ideal window for a transit is when Moho leads Kerbin by about 107o in its orbit, and the burn is conducted retrograde to Kerbin's orbit around the sun. Being at Minmus complicates matters though; it takes about two days after burning at Minmus to fall back to around 100km above Kerbin. Kerbin moves around the sun about 3.4o/day, while Moho moves about 14.1o/day, meaning that Moho advances about 10.7o/day with respect to Kerbin's position. Therefore, the burn at Minmus has to occur when Moho is only about 85o ahead of Kerbin. And this has to take place while Minmus is at the right position, about 1/3 of its orbit seems suitable for this. To further complicate matters you have the inclination change. Correcting for this can take over 700 m/s of delta-v if you wait until you are in orbit around the sun to do it. Being at Minmus allows for a nearly free inclination change though. If you wait until Kerbin is near an ascending or descending node with respect to Moho, then a small normal or anti-normal burn near Minmus can correct for most of the change. Of course, waiting for all of these factors to line up would take forever, so I just waited until I was at a node and didn't really worry about the position of Moho. With a change at Minmus I was able to decrease my inclination relative to Moho to about 1.5o instead of 7o. Once in orbit around the sun only about 200 m/s was required for the rest of the change. Here are both tugs burning near Kerbin after returning from Minmus. I got nervous during all of this time playing with maneuver nodes, so I sent up an additional fuel tank for the Talaria tug. Because this burn didn't really get me on course for an encounter with Moho I just treated it more like an orbital rendezvous rather than an interplanetary transfer. I partially matched Moho's orbit, then waited for the right time to set up an encounter. The final burn near Moho was about 500 m/s for one tug and 750 m/s for the other tug. The delta-v counts shown hear started recording when I left Minmus Orbital. Talaria made it with about 4800 m/s, not too bad, but it came in almost bone dry on fuel. Hermes had plenty of fuel since it was carrying the extra tank, but it took just over 5400 m/s to get there. Once in orbit the first matter was to dock the fuel tank to the central node. I'm trying out a new detachable docking component method here. The large docking port used for transit is attached to the fuel tank with decoupler. Once this is blown separatrons fire, carrying away the docking port, RCS thrusters and their tank. This kicked back the fuel tank a little more than I expected, but it worked pretty well, and now I don't have to keep all those extraneous RCS thrusters on the final station. With the central station node complete Hermes was docked to the large port on the docking node. This next part was fun. I had to maneuver all four station components into place while keeping everything from floating away. In retrospect, it would have been easier to just dock Talaria to the station first using the regular sized port on the back, but I didn't think about that at the time. The first solar truss was docked pretty easily. The second had some issues with my docking system, but all of the important parts survived intact. Next the habitation modules were moved into place. The cupola modules provide a lot of torque which made this much easier than the solar trusses. With all of the components in place Shepbro Kerman, never one to shy away from a dangerous duty, performed an EVA to secure the station with quantum struts. He returns to the station here, silhouetted against fiery Kerbol. Now here is the completed station. All of the docking thrusters have been blasted away, the tugs are docked, Talaria is hiding in the back, and the station is secured. Everything is pretty stable, even when moving around there's not much flexing or bending. I'm quite pleased with this station. I did some launch pad and VAB testing of the fully assembled station, but there's nothing like seeing it in orbit after actually putting everything together. The crew is ready for the next phase, to identify the landing site and to await components of the second station. Those tugs unfortunately are never going to make it back to Kerbin in their current state, so a fuel resupply mission will need to be sent. We'll carry on with that soon.

Picking up from where we left off, the Moho probe pack is all set for its transfer burn. When the launch window arrives the probe's engines ignite, taking it on a course out of Kerbin's orbit and into the sun's. After a mid-course inclination change and correction burn the probe is on track for an intercept with Moho. Arriving at a low periapsis over Moho. The orbital capture burn wasn't too bad actually, around 2800 or so m/s. Add in the 1700 m/s for the transfer burn, and another 750 m/s for the correction and inclination change and the total delta-v was about 5300 m/s, not too shabby. After establishing a stable orbit around Moho at an inclination around 85o the Sat Map probe was released. The probe moved into a higher orbit and began mapping the surface. It became immediately obvious that the terrain around the two polar regions differs greatly. The northern polar region is covered in mountainous terrain, while the area around the south pole is nearly flat and at a low elevation. While the surface was being scanned the probe pack began its automated lander sequence. The first lander was dropped off for a descent to the southern polar region. Coming down to the surface it's obvious how flat this region is. We can see from the ground that this region is suitable for a base and would make for an ideal landing site; it is a little barren though. As the second probe is released and descends to the northern polar region we can see that the region is decidedly more rugged. There is an interesting looking crater not too far in the distance, though. The terrain around the landing site is obviously not well suited to landing a base, it is an interesting site though, and the elevation is relatively high, around 5000 meters above the lowest point on the planet. The orbiting probe pack then enters hibernation mode, awaiting the arrival of the first crew. From orbit, they will control the next two landers and the rover, using them to identify the final landing site. Meanwhile, back at KSC the first station components are being launched. First up are the interplanetary tugs. This one is called Hermes, it is designed to carry two payloads, one docked to the front and the other behind it. It was launched on an older version of my 40 ton lifter. Next up is Talaria, the winged sandles of Hermes. This was also launched on the old 40 ton lifter. It is designed to carry two identical payloads docked to the front of it, while the port on the back is used to dock to stations. I didn't want to leave the front end of Talaria's payloads unattached, so I came up with a cap that could dock to both payloads and hold them steady. I couldn't figure out a way to do this in one craft though (I've come up with a few methods that might work since then though). So I launched this as a separate payload on my 2 ton lifter, then docked in orbit. With both ports attached Talaria is now ready to rendezvous with the other components at Minmus Orbital station. And now for the launch of my first base component, the docking ring and central node. The ring has one of each size docking clamp to accomodate any craft. Jebadiah 'Jeb' Kerman, mission commander, is at the controls, lifted into orbit on my 20 ton launcher. This is the fuel tank segment, launched on that same, old 40 ton lifter. The tugs and initial base components made it to Minmus orbit and docked at the refueling station. Some still-classified components are docked on the other side of the station, limiting what can be shown at this point. The Hermes tug is in its final configuration, while Talaria awaits the other base components. We'll continue soon with the final base component launches, the transfer to Moho, and orbital construction.

You can prevent monopropellant from being used by right-clicking on the tank you don't want used and clicking on the little green arrow on the right side (an action group setting for this would be great). This prevents you from draining an upper stage tank prematurely. Just remember to reactivate the tank when you want to use it. Also keep in mind that you don't need much monopropellant, especially if you don't plan on docking to anything. For non-docking crafts I generally only put a single 100 unit tank, or a few radial tanks, and a single set of RCS thrusters. This is usually enough to keep things going straight during launch and for whatever I need it for once in orbit. And really, if you are using some kind of manned capsule or lander, your upper stage craft might not need any RCS, just drop it off during launch and save yourself from carrying around all that extra mass.

For my next mission the administrators at KSC have decided to explore that often neglected and sun-baked inner planet, Moho. Part 1; Probes, and the base begins Part 2; Moho Orbital 1 Part 3; Moho surface, and getting the tugs home Part 4; Helios Part 5; Pyrois Part 6; So much fuel Part 7; Full power Part 8; Coming together on the surface Part 9; We can't stop now Jeb, not when we're so close Part 10; Home at last Moho Orbital Station | Helios Solar Station | Moho Ground Base Mods Used: Plugins: Mechjeb ISA Mapsat Kethane Quantum Struts Subassembly Loader Crew Manifest Actions on the Fly Maneuver Node Improvement Parts: KW Rocketry KSPX Kosmos THSS Large Structural Components Icarus Project I'll keep this initial post short and outline the basics of my plan. - I am to establish a manned outpost on one of Moho's polar regions, complete with a research station, living space, and several exploration rovers. - A series of probes will be launched to map Moho's surface, explore possible landing sites, and gather data for the descent and on conditions at the surface. - Two space stations will be created to service this outpost. One will be in a low, polar orbit above Moho. It will act as a rendezvous point and refueling station, and it will house two small landers for ferrying crew and supplies to the surface and back. More details about the second station will be forthcoming. - A series of mostly reusable tugs will be used to ferry station and base components from my Minmus orbital station to Moho, where they will be assembled in orbit or on the surface. Another vehicle will be designed to ferry crew from LKO to Moho orbit and back. - To facilitate the launching of so many components, and to preserve my sanity, I'll also be building a series of standard launch vehicles. These will be designed to carry payloads from 1 to 50 tons into LKO. I started by designing all of the launch vehicles. Not all of them will be used for this mission, but they should be nice to have in the future. This first series, from left to right, shows my 1, 2, 5, 10, and 15 ton launchers. There are two versions of the 10 ton vehicle, for 1.25 and 2.5 meter payloads. All of these are capable of getting their respective payloads into LKO with around 50 - 200 m/s of delta-v to spare. And all of them are designed for use with fairings, without those an additional 10-20% can be added to the mass of the payload. This next series is my 20, 30, 40, and 50 ton launchers. There are two versions of the 30 ton launcher, for 2.5 and 3.75 meter payloads. I tried to reuse components for each vehicle. The 5 to 20 ton launchers all use essentially the same booster rockets, just more of them. And the 40 and 50 ton launchers are basically the same, I just added a 3rd pair of boosters. I'll end this initial post with the launch of the probe pack using my 30 ton vehicle. The pack carries a small orbiting Sat Map probe on top, four identical probe landers on the sides to scout possible landing sites, and a small probe rover on the bottom that will be used to survey the final base site. I'll update soon with the probe mission to Moho and its initial survey, and I'll get into the first stages of the orbital station launch and construction.

Wow. I really like this base design. Since you have docking ports on pretty much everything it shouldn't be hard to add a detachable lander system to each part. You could make the system reusable, or just blast off each skycrane after landing each segment. Is there any reason why you can't simplify those long structural segments? Instead of 3 segment long sections, you could just replace some of them with 9 segment pieces. It can be a little tricky to fly and land such long contraptions, but it's not too hard. It will also save a ton of parts (docking ports and landing legs) and require many fewer launches and landings to get everything on Minmus.

My first successful Mun lander. Worked great for landing on Duna; not so great for taking off again. Enough to get from LKO to the surface of Minmus and back, with plenty of fuel to spare. Ion engine lander for Minmus, because why not? Three ion engines are on the back with a single xenon tank. Blast-off from Vall. Fun times on Tylo. Bop and Pol. Mun rover lander; it just takes a little push to tip it onto its wheels. A variety of base component landers and the systems for getting them into position.

I agree that solar panels are the way to go. I put some batteries on ion probes, but just enough to give me a little leeway for times when I'm behind a planet or a I can't orient the solar panels in the right direction. They burn through energy so fast that batteries would almost never be an effective way to power them. You just have to be careful with timing your maneuvers and it will take many short burns to build up enough velocity. My ion engine landers thread has lots of different examples of the types of crafts that work well. They can't be used long in the shadow of a planet or moon, but through careful timing that was never really an issue.

Yeah, 10k is probably enough, but you have to really get the timing right. Maybe 12k is better to give you some leeway.

Tylo is a tough one. My lander was quite a bit bigger, it required a lot of radial fuel tanks and staging, but it worked. My final ascent stage was only a bit smaller than your entire craft. A few radial fuel tanks probably would have been enough for you to take off again. But I do admire the attempt at landing and returning with such a minimalist craft.

That's a good idea, put some radial tanks for the Vall landing and take off, then just leave a really small lander in the center. Bop and Pol require almost nothing just to land and take off from, I think a single LV-909, the little lander engine, and a either a 90 or 180 unit tank would be enough for part of the Vall ascent and a Bop/Pol landing and return. You will have to be careful balancing your original carrier though, the heavy lander will make it difficult to control until you can get rid of that weight. I had this problem on my Jool moon mission. My solution was to activate and deactivate a nuclear engine on the side of the heavy Tylo lander to keep me pointed straight. It was a lot of trouble, but it worked pretty well.

Yes, it depletes very quickly actually. You can use the kethane debugger part to cheat and and recreate another kethane patch where you are, or you just have to make your miner mobile.

I believe that only the originating point of the strut is counted as a part. After you stage a little nub remains where the strut attached, but I don't think that is counted as a part. So I think it's better to put the initial point on the lower stage and connect it to the upper part. Though I'm not sure how much of a difference this actually makes for performance. And no, more struts does not always make your craft more stable. I try to use as few struts as possible. If you find that you have almost as many struts as other parts then you probably need to redesign the ship. The strutting tanks together thing is definitely a good idea. I do it all the time when putting a small grey tank below an orange tank to prevent overheating. Without struts that grey tank wobbles all over the place, but 3 or 4 short struts keeps it stable.

Yeah, that's what I figured. The mass of the engine plus the solar panels needed to power it is too much for the Mun. I tried some of the bigger, more efficient Kosmos panels, but they were too heavy, too. Another thing to keep in mind about these ion engine crafts is that the in-game description lies about the electricity requirement. It says 12 E/sec, but it should be more like 14.5 E/sec, unless they changed it for .20. That small difference has a huge impact when trying to come up with these kinds of designs.

In that case you're going to need at least 4000-5000 m/s of delta-v just for getting into and out of orbit from the 3 moons.

Thanks, but the Tylo lander could use a redesign. Everything else worked fine on the first attempt, no reloads, but that Tylo lander took about 15 tries. It just doesn't have enough TWR so landing burns way more fuel than it should, and the landing struts block the radial engines. I really like the overall design though, I think maybe some slightly bigger engines on the bottom of the radial tanks could improve it a lot. Edit: Anyone know how to get this thread moved to mission reports? Spacecraft exchange doesn't really seem like the right place for it. I can share .craft files if anyone is interested though. Edit: Thanks for moving this

Yeah, building simpler and smaller rockets makes everything else easier. And you really don't need much at all to get to Minmus and back. While coming up with a series of standard lifter designs I made this design using my 5 ton lifter. It has more than enough to land and come back, I think it could even do a powered landing on Kerbin, but I accidentally released the engine while I was landing.

I made a manned Minmus ion lander, so a hover craft should be no problem. I even used the gigantor panels, more efficient solar panels should make it even easier. I have a mission report thread for this. I did Bop, Pol, Gilly, Ike and Minmus, I got bored before I tried Dres and I couldn't get a high enough TWR for the Mun.

I did something similar to this a little while ago, but I dragged along a Tylo lander, too. Are you planning on taking the station along to each moon, or releasing the landers at some other point and having them return later? It takes almost nothing to land and take off from Bop and Pol, but it takes a ton of delta-v to get in and out of orbit around each moon. It is possible to use Tylo for the inclination change though. I've done that before going from Bop to Pol and it worked really well, but I didn't plan in it, I just had lucky timing. Vall takes a lot to land and take off from, I think around 1100 m/s. You can see my post here for a lot more detail about how I did all of this. http://forum.kerbalspaceprogram.com/showthread.php/29028-Manned-Jool-survey

Challenge accepted and completed. On Minmus no less. See here for more. http://forum.kerbalspaceprogram.com/showthread.php/30329-Ion-Engines-Everywhere-My-Attempt-to-Land-As-Many-Places-As-Possible?p=387690&viewfull=1#post387690

For my Pol and Bop landers I decided to just do everything at once and launch both together. Both landers are on top, the Bop lander is a bit bigger with 3 ion engines and a few extra solar panels, the Pol lander has just 2 engines and 4 gigantor panels. I went for Bop first because that lander is on top. I used the transfer stage to get almost into orbit, then released the lander and finished off the orbital insertion. Bop is a bit treacherous being so absurdly mountainous. But, I landed easily, well, if you don't consider what happened next. Stupid hills... But the probe survived intact. It really only needs one panel once it's on the ground, so I'm not doing this one over again. Back to the Pol lander, I used an encounter with Tylo to get into the right inclination and bump my apoapsis up to Pol's orbit. Once in orbit I dropped the transfer stage into Pol and began my descent. Another steady approach. Pol is bit less hilly than Bop, but still fairly uneven. And another successful landing, after I stopped sliding. This time everything stayed intact though. And now, just because I can, I give you the manned ion lander. This seems like a good idea. I went for Minmus and landed next to a rover that's been exploring there. The lander is about the same as my first Minmus lander, I just added the chair and a few extra solar panels to let me use full thrust. A reunion on Minmus.

There seems to be an issue with the strutcore part in the updated version on spaceport. See here for the fix: http://forum.kerbalspaceprogram.com/showthread.php/30775-Quantum-struts-and-fuel?p=384733&viewfull=1#post384733

Do you have something enormously heavy on top of everything? Also, you could try removing everything on the sides, and the struts with them. If this makes it more stable then you might have too many struts and connections between parts above and below the decoupler.