Horn Brain

Ah! Perfect suggestions.

Putting together a list of organically-arising challenges in the game over here: http://forum.kerbalspaceprogram.com/showthread.php/32194-MetaChallenge-Thread?p=398694#post398694 I feel like this is a good way to start when trying to determine how "accomplished" a player you are.

That is fantastic, starkllr. Good on you for not giving up and learning something new. You'll get the hang of it and before you know it you'll be building these in orbit: (album: http://imgur.com/a/HYyAY)

I like to use the Orion architecture of a small, very well-tested and safe crew capsule designed to deliver the crew to the mission and provide return capability. I usually try to send up my crazy landers and interplanetary behemoths with a little probe core attached to them so that they can be launched empty. This usually comes in handy, anyway, since it lets me more easily take the whole crew down to the surface without having to leave a sad Mike Collins-Kerman minding the orbital stage while Jeb and crew bomb around on the surface on awesome rovers. That takes care of most launches, which is where I see probably 90% of my fatalities otherwise. Sometimes I will have to send a vessel up with a crew, like the Eve return lander which was so critically weight-sensitive. Those times I will just do a few tests and call them "simulations" since I don't have access to wind tunnels, CFD software, or accurate FEM analysis for the structural performance. I always fly the final mission "live" though, and if possible I have some abort mechanisms I've developed which have saved a handful of crews from stack collapses and such. Now the other places where I can lose crew are botched landings/ascents on other bodies and running out of fuel. There really is no perfect abort scenario for these situations. If the landing is going awry, the best thing to do is to just abort to orbit, but if you've lost control that might not be possible. The trick is to use very conservative designs that you are dead certain will be stable, and then be ready to abort the landing when the time comes. Obviously, there is no abort scenario for a failed ascent, so I tend to give my ascent stages a very hefty margin of extra dV to make sure I don't screw up. If I run out of fuel, I will always go get the crew if they have enough living quarters that I deem them capable of surviving the wait. Even this can be very terrifying if the fuel were to run out, say, halfway through a burn from Jool back to Kerbin. How do you do that rendezvous? So basically there are lots of ways to die in space, but I try to do the best I can. Now my spaceplane program... that's a whole 'nother story. Oh, the horror!

Updated with the suggestions I thought were not already subsumed by other challenges or artificial. I don't want any numbers here, really. 100 m/s isn't a natural barrier in the game to land vehicle speed. There are also not going to be any "Get X tons to orbit, land X tons on a body" type challenges. The mass of the vehicles should be determined by design and mission requirements, not arbitrary limits. For example, if you want to get to orbit on Tylo, you're going to need a hefty ascent vehicle, so that challenge already includes the subchallenge of landing a heavy payload on Tylo. That's the spirit of these challenges. Thanks for the help!

Careful, if you put clones in the same capsule, they will annihilate each other and disappear. They can be in the same ship, just not the same capsule.

I was wondering after reading this thread: How do we measure our accomplishments, anyway? What I want to do here is collect a list of "challenges" of different levels that are built into the game, just like there are certain challenges built into the real world, for example: Reach space, get into orbit, rendezvous with another vehicle in orbit, land on another body, etc. Here's the plan: Let's put together a list of the fundamental challenges inherent in the game. They should be big steps for a player that's never done them before - the kind of thing that you'd be willing to build a mission just to test your ability to pull it off before incorporating it in a more complex mission in the future, or the kind of thing that you'd take a screenshot of and be proud. I'll start with a few examples, and then I'll try and keep the list updated and categorized. Add your own! I think I'll print this out and keep it on my desk with marks to indicated that I've done the things and marks to indicate whether I've done them manually or with MechJeb assistance. ROCKETRY - Hurdles to overcome for rocketeers. Reach Space (70km) Reach a stable orbit Escape Kerbin's SoI Perform a targeted reentry from orbit Land intact on an airless body (Mun, Moho, etc.) Reach solar escape velocity Crash into the Sun Return to orbit from another body [*]AERONAUTICS - Hurdles to overcome for aircraft and spaceplanes Build a stable aircraft Land safely Land safely on the runway Circumnavigate Kerbin with an aircraft (i.e. don't go to space) Reach space Reach orbit Single Stage To Orbit Single Stage to Orbit with a significant payload or significant fuel reserves for maneuvering Reenter and land safely Reenter and land safely and on target Enter and land safely on another body with an atmosphere Return to orbit from another body with an atmosphere [*]ORBITAL MECHANICS - Challenges regarding navigation and precision Circularize your orbit Achieve a polar orbit Achieve Keosynchronous orbit Flyby the Mun or Minmus Orbit the Mun or Minmus Successfully perform a gravity assist to some useful effect Encounter any sun-orbiting body Orbit any other sun-orbiting body Return to Kerbin from another planet or dwarf planet Rendezvous with another vessel Dock Build a space station via orbital construction [*]UNIQUE CHALLENGES - Challenges specific to a particular body Return to Kerbin from one of the moons of Jool Reach Moho, Dres, or Eeloo orbit (grouped to avoid repeating myself) Land on Moho, Dres, or Eeloo Return from Moho, Dres, or Eeloo Land on Tylo Return to orbit from Tylo's surface Return to orbit from Eve's surface [*]AESTHETICS - Challenges that don't fit in other categories, but that somehow still need to be done. Find and visit an anomaly Deploy a functional rover on another body Copy the Apollo architecture on a Mun mission Get to orbit using only EVA pack and possibly a kick from an engine exhaust

With the way drag works in the game, I think you're better off just using rockets. Spaceplanes actually use more dV to get to orbit than rockets, I think. The reason they're more efficient is because they can use jet engines which have a much higher effective Isp, so you get more dV for less fuel in the atmosphere. You can't use jets on Eve so you're out of luck. The only option left to you is ion engines, but those have trouble getting things off the ground on Kerbin, let alone Eve. Balloon ascent is the way to go with the current drag model, but after that, rockets. I made a 60-something ton lander that could return from about 4.5km altitude (which gave you some alternative landing sites away from the one tallest mountatin). I never liked the idea of making kerbals hold onto ladders while doing supersonic ascent, but maybe now that we have actual seats you could build them a little windscreen. Cutting the pod obviously saves huge amounts of mass on the lander.

You youngsters have everything the easy way. Back in my day, we didn't have struts. If you built a rocket with more than one stack, you had to use a little thing called DESIGN to make sure that the craft would just go into a nice spin instead of wobblin' all over the place and smashing into itself. And if it DID smash into itself? Well you just jettisoned that stage and kept on going to orbit, because we were PREPARED for these sorts of things!

On my fresh install, I got three Jebs, Bills, and Bobs in a row on my first three missions. I think I got another Jeb on a solo mission too. At first, I was afraid to keep so many of them around for fear they might annihilate like anti-particles so I made the first clone reenter on EVA... Now I keep them in separate hab modules on my space station to ensure against the loss of our most popular kerbonaut. I can just replace him with a clone and brutally suppress the news of the previous mission ever having been launched. K is for Kremlin. Glorious success vill be ours alvays!

Pros of this update so far: I CAN LOOK AT KERBIN! (without lagging) Great job with the texture fix, guys! The skipper engine is EXACTLY what we needed. THANK YOU! The Cupola and mini lander are beautiful inside. LARGE. DOCKING. PORTS. YES! This makes space station and interplanetary vessel construction so much simpler and less headache-inducing. Being able to click on apoapsis tags and keep them open so I can adjust on the fly. Brilliant! Being able to change root parts is wonderful as well. The seats are really cool. I built some super minimalist rovers out of just the short I-beam, an RTG, a battery, four small rover wheels and a seat, and the thing is a blast to drive around. Can't wait to install my "serenity module" on my station, consisting of a long beam with a seat at the end of it where kerbals can go be alone and think. Attaching pieces in the VAB seems to have been polished quite a bit. Not nearly as many random instances of things not fitting where they should. Cons so far: My space station blows up every single time I switch to it from a nearby vessel using [ or ]. Luckily, it's not a huge deal if I remember to save, but it was frustrating at first. Wheels jitter causing rovers to suddenly get airborne. Sounds like Harv has this under control, though. The seats aren't perfect yet. When you fall out of them, sometimes you can get stuck inside part of your vessel. This is not a big deal. Sometimes kerbals and other parts freeze and won't respond to some inputs. My rover on Vall wouldn't turn off the parking brakes once, and a kerbal was frozen on the launchpad after I switched away from him and back. That seems to be new. All in all, this update definitely fixed way more things than it broke. I was not expecting a whole lot from this one, so it was a very pleasant surprise. The little things that were fixed were all things that made the game more polished. This makes me feel like this team really wants to do all of the little things right in this game. Despite the fact that there wasn't a whole lot of brand new game mechanics, the few things that were added really opened up the existing mechanics and made the game more fun. Bravo, team! Can't wait for the next one already!

The (meatspace) Sun's sphere of influence is finite. If you go out far enough, the dominant gravitational field will be either the galaxy's or some other star's if you happen to be close to one. Obviously the Sun never stops attracting you gravitationally, but neither does the Earth... or your mom, for that matter (this is, strictly speaking, not an insult). Kerbol right now does not have a galaxy in which it resides (just a painting of one on the night sky), so its sphere of influence is actually infinite. You can still escape from it, defined as having a positive total energy with respect to Kerbol (sum of kinetic and potential energy), meaning that you will never be recaptured by Kerbol's gravity and will instead continue forever into space. Why do people struggle with this so much? Everyone understands that the Earth has a sphere of influence within which it is the dominant gravitational body, and outside of which the Sun is most important. But mention the Sun's sphere of influence and everyone loses their minds! /joker

I really hope that the mission planning and automation feature gets added. Being able to perform routine missions (resupplying bases/stations and harvesting resources from known deposits, mostly) automatically without player involvement would really open the game up for enjoyment. Imagine not having to fly those four refueling missions to your station yourself after topping off a big spacecraft for a mission to Moho or out past Jool! It would save so much time and tedium, and you could still do the missions yourself whenever you felt like getting back to your roots, of course. I feel like this is exactly what was missing from the Spore space stage, and it's what led me to give up the game once my empire got so big that I spent most of my time performing tedious tasks like repelling the exact same Grox invasion for the 50th time and flying loads of spice all over the place instead of exploring. Please, O devs, hear my prayers and do not forsake this aspect of the game. Everything else is gravy as long as I get to do mostly exploring and tinkering instead of running the same refueling mission over and over. I'm even fine with the Kerbals screwing up once in a while, so long as I can just activate one of my saved replacement missions to re-establish the lost assets and keep going on with my exploring. That's the reason you train them, after all, so they won't screw up. Also, hoses. But I digress...

I don't think you understand. In reality, if you put an aerospike on a NERVA, the thrust will be basically the same. So a NERVA aerospike should have roughly NERVA mass, thrust, and efficiency in vacuum, but better efficiency at lower altitudes than a regular NERVA. It should not have Aerospike thrust with NERVA mass and efficiency. That's just "cheating". By that I mean "not representative of reality" or if you prefer, "a straight upgrade to a stock part". I think to get a realistic performance out of that arrangement, you should subtract the aerospike's mass from the NERVA's mass, leave it shut down, and just edit the aerospike engine to have: Low mass (since it's just a penalty) NERVA thrust (60 kN) 800s vacuum Isp ~500 or ~600 sea-level Isp Then it will look and perform roughly like what this arrangement could potentially produce in real life.

So you've rigged all that up and edited the part files too? Why is there a fuel line running to the aerospike if it's just a nozzle?

That looks cool, zekes, but just burning a nuke and an aerospike at the same time is not what I'm talking about. It would have to be a new part in the game, but in real life you can just put an aerospike nozzle on an NTR. You should be able to get an aerospike nuke with 800s of efficiency (or at least much better than the other liquid rockets) all the way down to sea level. The issue becomes TWR, but I think that it would help significantly if you had a 600 or 700s Isp engine that worked in Eve's lower atmosphere. It would be like a nerfed version of using turbojets to get to orbit on Kerbin.

The forum monster ate all of my hard work and analysis, but I did a big thread about this issue a while back. The gist of it is: to minimize overall fuel expenditure (including getting the fuel for your refueling depot into orbit) you should have your station as low as safely possible. To maximize the amount of fuel left in your tanks when you leave Kerbin, you should refuel as high as possible (this is easiest to do at the Mun or Minmus), then dive down to 70 km at just the right time and give a small burn to escape Kerbin. I can't seem to find the thread in any caches, but if you want to look for it, look for "where should I put my station, I do the math so you don't have to", something like that, and my name and you might find it.

The difference between an aerospike engine and a regular one is just the nozzle. Imagine if you could put an aerospike nozzle on an LVN and get perfect efficiency all the way to the ground. I think that would probably make Laythe return very easy. Maybe even Eve, although TWR is an issue there. You could certainly make some very efficient SSTOs for small vehicles on Kerbin.

If you want to land on the Mun using only a kerbal, you can lower your velocity with your spacecraft to below about 500 m/s, then bail out, and you may just barely be able to land if you do everything perfectly. You'll also have to correct the velocity of the spacecraft too or it will crash. You need just a tiny bit more fuel than you carry in the pack to get to orbit on the Mun, and landing usually takes more fuel.

You can launch to orbit OR land using only a kerbal's EVA pack on Ike and Dres. You can land AND return to orbit using only the EVA pack on Gilly, Minmus, Bop, and Pol. So it's a handy way to rescue your mission if you crash your lander on any of these worlds. On the Mun, Eeloo, and maaaaaybe Val and Moho, there's a good chance you can bail out of your ascent stage and finish getting to orbit with the EVA pack if you just get a bit of velocity from your under-fueled lander, as well, so keep that in mind. I remember when I was trying to perfect flying my stock Eve lander back to orbit, I once ran out of fuel with just 200 m/s to go to orbit so I bailed out and finished with the EVA pack to save the mission. That's kerbal space program for ya.

How about some current-generation possibilities? The one unmanned mission I am most excited about is sending a melt probe and an autonomous submarine to Europa to get into the oceans. If you haven't already seen this, get ready to have your mind blown: Sadly the JIMO mission was cancelled, and it never had a melt-probe-submarine planned for it. HOWEVA! We do have all of the technology for this available to us right now. The only thing I'm not sure about would be communicating through the ice to the surface (and then to an orbiter... and then home...). The obvious solution of leaving a wire behind you would be heavy (3 to 16 miles long!), as well as easily disrupted by a single icequake on Europa (we don't know how stable the ice is, but it is covered in huge cracks). If the sub is powered by a nuclear reactor instead of just RTGs, it should have plenty of power for very strong, ice-penetrating radar which could be used to communicate with the orbiter (maybe?). That, to me, is the biggest challenge. Most of the other problems are solved if we can simply use a small nuclear reactor on board.

One thing I can tell you is not to feed fuel from your payload back to the lifter unless you need the thrust from the lifter. If the payload has enough thrust to do the job of finalizing your orbit, then it will almost surely be more efficient than a mainsail. This will mean less orbital refueling for you later. The staging process is a trick to increase your effective mass ratio in the rocket equation, thereby giving you more dV. Drop as much dead weight as soon as possible. Ideally, you would drop every tank as soon as it is emptied, and drop every engine as soon as your TWR without it is around 1.5 to 2.0 (during the vertical ascent portion). The problem with asparagus staging is that when you drop engines you are increasing the fuel fraction of the remaining vehicle. That's good for overall dV, but bad for TWR right after staging, and the lower your TWR, the more gravity losses you incur. The trick is to find the balance. From my experience, the ideal ascent profile goes like this (ignoring noble objectives like not raining death on the launchsite): Launch: High TWR first stage should sprint up to terminal velocity and then run out of fuel immediately afterwards and be dropped. This is where solids come in handy, but the first stage of a large asparagus stack does this job just as well. Climb: To maintain terminal velocity, you only need a TWR of about 1.5 or higher in the lower atmosphere. This is when you can dump engines and tanks to save weight because you don't need the thrust until you pass 10 km or so. Gravity Turn: I usually use an actual gravity turn where I learn when to tilt over and follow the prograde vector (first surface for aerodynamic reasons, then gradually shifting to orbital as drag diminishes) and still end up with a nice ascent profile. Here you want high TWR again because the atmosphere stops being important and you really just want to be going as fast as possible as soon as possible. Apoapsis tuning and Circularization: At this point, I'm usually moving at 70 to 80% orbital velocity or higher and TWR is no longer important. If I did my gravity turn right, I should have plenty of time to apoapsis so I usually just use an LV-T45 or 30 for this stage, or maybe a poodle if it's heavy enough that weight is not a factor. Those are my methods. I hope they are useful to you. Anyone who thinks I'm doing something very stupidly should feel free to chime in. I'm always trying to improve my lifters.

That's false. You can blast kerbals and other parts at hundreds of m/s using rocket exhaust. Try it: Put an engine on an action group, back up the nozzle to a small part in orbit, then full throttle and switch the engine on suddenly and then off again. Your velocity will be only slightly different, but the other part will be moving hundreds of m/s. I use this trick to deorbit small space junk like stage separators.

-snip- If you just want to be able to make a four-booster asparagus-staged lifter, the easiest way (I think) is to make one set of boosters using 2-way symmetry but without the fuel lines, then copy them (hold Alt+click on the decoupler) and place the copy on the main stage. You should now have the four boosters. Now, with 2-way symmetry still engaged, link on booster to another, then link the second booster to the main stage using fuel lines. The last thing you must do is make sure that the decouplers fire in the right order, which should be easier since they should appear in groups of two in the staging menu. If that isn't what you wanted, please try again. Maybe ask someone you know who speaks English well to translate for you so we can understand what it is you want. Alternatively, ask in your native language and maybe we can google translate it/someone here speaks it.

I think I can do this with a 30-odd ton vehicle, 8 small SRBs (to get the vehicle to orbit in one piece), a separate rover, one big orange tank in LKO and about 3/4ths of one in LE(ve)O. Here is an album with the vehicle in orbit: http://imgur.com/a/SbYDz#0 Read the descriptions beneath the pics for more info. Dante has well over 10 km/s of delta-V. The final payload to orbit will be only the very top probe and two small toroidal tanks with three ant engines. I may just barely be able to do the full return with Dante alone, but I'm expecting to have to do a retrieval mission. That can be quite light, though.