r_rolo1

As I'm a nice guy, I'm going to post the lander without mechjeb ( I want to see more good ideas ). See here

12 (!!!!) aerospikes + 1 LV in a lander ? + 12 big parachutes and a small one ? You really like to play it safe ... Well, before entering any idea on how to make a launcher for this, you might want to review your fuel lines and staging in the launcher. You can definitely do it in a more efficient fashion. On the launcher, as I can't launch the game now, I can't mount it but I have some ideas that revolve around using all of those engines you already have ( 12 aerospikes can deliver roughly the same punch than 3 of those big engines ) to assist in the launch...

True, and it is exactly as unstable Well, this particular ship is not that unstable as that, but my experience with this kind of design so far is that in general ships pulled up by engines are very susceptible to lateral tilting and that it can be hard to balance things. I tend to resort to some kind of hybrid solution ( a engine in the bottom of rocket axis and 3/6/12 smaller engines in the top pulling ) that normally ends working well enough.

Thanks for experimenting this one Kosmo-not. I surely respect your minimal ships and your fine pilot skills being applied to my humble ship I have full conscience that this ship as posted is horribly inefficient at launch and your change makes sense in terms of improving the efficiency of the design. But this was pretty much a concept ship just to show up that particular solution I had weaved out ( and that I've already deployed in other designs ) so I'm ok with inefficiency. And, let's be honest, the crazy simplicity ( or the simple craziness ) of the design is half of the charm

As you learned painfully the small 1m engine was not made for landings of anything more heavy than 4 or 5 kerbal weight units Next time just add a decent engine and you will be in far better position Oh and you definitely could do with less, especially less SRB .I'm sure you could land in Eve or Murs in .17 with that rocket, so using it for training in Kerbin SoI seems a little wasteful

I have not tested the chutes very extensive but when the chutes break like that it is because there are too many or too little parachutes and/or the reentry angle was too steep ( hence the chutes have to break out much more energy that might be too much ). I'll test them later when I have time. And you are right, there is a stage that is useless ( stage 8 ). I forgot to solve it before I delivered it out. The staging is complex but it can be resumed by: - stage 9 fires all engines except the smaller LV - stage 8 + 7 drop the solid boosters out ( they were supposed to be one stage ) - the next 3 stages drop the outer tanks, starting by the lowest ones and then climbing - stage 3 separates the central big tanks and 3 of the aerospike engines out also firing the small LV. In other words it separates the lander out. - To be honest I do not remember well the last stages, but after activating the parachutes and supposedly landing, they should separate the tanks with the legs and the tanks with the engines by that order. That particular design is the heritage on my work about rockets that pull their cargo instead of pushing it. I even posted a quite crazy prototype of a Mun rocket the Accordion B: You can definitely see the thought line connecting Eve I and that crazy thing ( really, it is a fun rocket to fly ) To be honest I like the concept because it allows more engines burning at takeoff with some imagination and because you can drop all of the tanks as soon as they get dry, making things more efficient. Unfortunately it has the drawback of making the ships extremely unstable and susceptible to lateral tilting, especially if the engines are not mounted directly adjacent to the central tanks ( I strongly suspect of possible physics engine shenanigans ). That can be mitigated if you also put a strong push below, hence that LV in my Eve I design. And OFC this are nothing more than prototypes. We can't really test things before we have the planet to try to land on . But to be honest, I'm seeing some good ideas in this thread and will rip them out a lot

Unfortunately I discovered that Eve I is taking advantage of a rather esoteric fuel bug ( yes, another bug ... completely unrelated to the the non-full thrust one ) that cuts the fuel consumption in half in certain situations. See here for more details. I think it might still work but it will definitely not be as efficient as I posted it...

Unfortunately I discovered that Eve I is taking advantage of a rather esoteric fuel bug ( yes, another bug ... completely unrelated to the the non-full thrust one ) that cuts the fuel consumption in half in certain situations. See here for more details. I think it might still work but it will definitely not be as efficient as I posted it.

*cry* Really? So basically of my rockets in .16 are useless in .17

Really? Can you give a link for more details ? I only knew the more popular non-full burn one ... now I'll have to redo all of my aerospike rockets

True, but I can't make tests on bigger ships of this model without being Krakenized in 0.16

This ship is the natural complement of my other Eve rocket, the Eve I: this is a 3-man capsule rocket designed to go to Eve orbit, maybe do some aerobraking, rescue any stranded Kerman that is there and go back to Kerbin: The instructions are roughly the same than the ones for Eve I ( also has a mechjeb and a stock version ): fly it to a 70x70 km orbit, wait until +/- 40º after the sunrise line and burn prograde until the Kerbol orbit has a Pe that matches the Eve one. I also must add that launching it ASAP ( that is, as soon as the physics kicks in ) is highly advisable and that sometimes the ship collapses under its own weight ( it happened a couple of times in restarts for some reason ). Here is my test run: I'm quite confident that this is enough to come back from Eve ( not sure if it is enough to brake inside of Eve SoI to enter orbit and come back but I'm counting in aerobraking a bit. If needed I'll scale up the design but so far this is pretty much the limit of this design without getting Krakened ) Craft of both Mechjeb and stock versions here

Fair enough To be honest I'm pretty sure that it will be impossible to make the full trip in a single rocket launched from Kerbin ( same as in RL Mars and Venus ). As such, this is simply a one way trip rocket ( well, it is planned to launch the capsule back into orbit for a hypothetical rescue ).

Inspired by Guard13007 Eve going thread and after the fiasco of my last Eve rocket ( that was krakenized still in the atmosphere :| ), I decided to make a less Kraken-friendly ship, that could still land a Kerman in Eve. Thankfully Nova came to the rescue and gave some important intel: Knowing this, and basing upon some of the work Guard13007 did ( especially on the Eve lander issue ... the lander stage is a heavily modified version of his last posted lander ), I've decided to work in my Confusion A to make a little less complicated ( thus less Kraken susceptible ) and put one leaner lander on top, in the hope that it could get to the orbit Nova posted. So I got to this: First, the ship in pic has mechjeb, but it does not need it to fly if you're good enough pilot. You just need to be extremely careful in the launch staging, to avoid waste ( it is a fairly complicated staging ) and empty tanks hitting the central engine ( it can happen if the ship is ill manoeuvred during empty tanks ejection ). Second, the ship without the solid boosters could also get into the desired orbit but it would leave little fuel for manoeuvres ( I plan to use mostly aerobraking to slow down the ship to a Eve centric orbit ( or even a direct drop if I feel daring enough ) so it is not needed as much as that if Nova data above ( especially the atmosphere density ) is to be relied on ) so I decided to add some extra punch. Anyway, flight plan: - Get into a 70x70 km orbit or as close of that as humanly ( or mechjebly ) possible... makes the ( supposed ) Eve injection burn more efficient. As I said above, be extremely careful with the staging.... I started turn at 10km, but I think that can be optimized. Anwyay you will most likely need to go full throttle until you circularize so no problem with the Fuel bug - Wait until +/- 40º after sunrise line ( this is on the day side of Kerbin ) ... I need to really calculate this using one of the threads in the How to section since this was completely eye-balled. Then do a full burn until the Pe of the Kerbol part of your orbit is 7440000 km or close enough ( you will probably need some low throttle burn in the end of this to fine tuning ) My better try left me with a 1/3 of big tank to later orbit corrections: [spoiler=] Craft files for both Mechjeb and stock versions here . For the slightly refined version ( Eve I a ) , see here

Why? It is nothing more than a rescue operation to Eve, to save a stranded Kerman that got out of fuel . The fact that it was by design it is a mere accident Speaking more seriously, it will be most likely impossible to simply build a huge mega rocket for a complete trip to Eve and back as long as it is launched from the surface of Kerbin due to the not enough energy density from our regular rocket fuel. In RL we have the same issue with trips to Mars or Venus ... The RL solution for that would be most likely to assemble a ship in low Earth orbit, fill it with fuel ( delivered by other rockets ), burn to target planet, deploy a lander , land, get back to mothership, burn to Earth, deploy capsule ... Unfortunately this needs 2 things that KSP still does not have in base version ( both exist in mods though ): docking and fuel transfer. Not having those, the only realistic option is the two ship mission as the OP wants. Back on topic, @ Guard13007 , your X6 is completely excessive fuel wise. I've been tinkering around a heavily modified version of your X5 and I got a decently performing ship that can put a lander slightly heavier than your X5 in a orbit with a Pe consistent with the data Nova gave with a 1/3 of a big tank left for manouvering ( the ship in the pic has mechjeb, just for convenience of the launch staging, that is somewhat complicated, but it does not need it ) See here for save and more details

He does not plan to come back to Kerbin in this ship His OP has it all explained: the plan is to send 2 ships, one for the landing and other for the return from Eve... obviously this is the lander itself. The return ship will be most likely one with a 3 men capsule but with a kerbal left in home to make space

Just to point out that your landing instructions for X5 are far from optimal. Using the engines with the parachutes deployed but not open is a waste of fuel because you will have the same terminal speed as soon as the chutes open ... So you should cut step 3 and I'm not even sure if the step 4 could not be optimized by burning at higher power but starting closer to the ground BTW on X6 ... your pic shows you burning at 300km high. If possible try to burn for escape velocity closer of the planet, because burns are more effective when the ship is at a higher velocity and lower orbits = higher orbital speed.

Not wanting to look ungrateful ... but the atmospheric density profile of Eve is equal to Kerbin or atleast similar ? As aerobraking will be a primary slowdown manouver there it would be nice to know ...

As 0.17 is coming , I started (over)engineering a ship that will atleast let me flyby Eve ( and hopefully land on there after adding parachutes and landing legs ). So ,after some concretion work, I got to this : It even appears a simple ship, but it is definitely a unholy mess of struts and fuel lines ( there is lots of work in the plumbing structure ) and follows my principle that a engine that does not fire at launch is dead weight for quite a while ... so all the engines except one fires at launch. It is also a slide show producer ( in spite of the pic showing a mechjeb-less version, I was forced to use mechjeb for the launch sequence because of that ... ) so use at your own peril. The Kraken also loves it and it will start spinning at very low altitude ( 50-60 km ), so the tests on this ship will be halted until 0.17 comes out Anyway I leave here a zip with both the stock version and the one with MechJeb. As I could only launch with mechJeb, I can only say instructions wise that you should fire as soon as the physics kick in ( the bottom engine tends to break out of the ship due to the weight if you don't fire out ASAP ) and to use the standard Mechjeb flight plan ( not even thinked on optimizing it so far ).

I am pretty sure that the OP meant that the ship at challenge start must be in a orbit that has a periapsis above 0 ... I assume by this that if the orbit Pe is above surface , anything goes. The beef is that it is highly unlikely that a faulty ascent will happen exactly after you reached that ...

Your X3 would probably win if you used the big parachutes on top of the lateral tanks ... And may I suggest aerospikes instead of the LVs ? They have by far the best thrust/weight ratio and they ( still (?) ) do not have reduced performance in thick atmospheres, making them the natural engines for a lander stage in a thick atmosphere planet , like Kerbin nowadays and also Eve in .17

That is pretty much the crux of the argument. I can understand how people that play KSP mostly to pilot rockets and have the necessary motor skills and maybe fine tune hardware for that will probably have more fun doing a full human controlled mission, but the people that have inate or hardware related issues controlling the rockets would be heavily frustrated with the game fast if there isn't any way of removing that stump block of their path and the persons that play the game to build rockets would probably dislike that emphasis in hard-stick piloting. And let's be honest, RL automation is here for a long time ... in fact the overwhelming majority of the global lot of space missions made so far was made in a automated or at least in a semi-automated fashion, even if you don't include the routine sat launches :/ Agreed. Orbital transfers are a precision issue by itself and only the fact that the relatively big angular dimension of the Mun and Minmus SoI seen from Kerbin makes it possible to use eye balling with consistent success for most people ....

The lack of symmetry on that ship is disturbing My experience with skycranes in KSP ( see here for the most successful design so far ) showed me that in general ships pulled by engines are ridiculously sensitive to lateral tilting, even if the ship is perfectly symmetrical. I can only imagine how bad can a 2 engine ( extra sensitive ) nonsymmetrical ship can be

Well, note the clarification that the ship that starts the descent must land in a whole piece, unless you consciously jettison out parts of it That makes things not as easy as that ... Back on the beef, I've been trying to do this on Kerbin and I'm pretty sure it is doable with some luck and a computer that does not choke near Kerbin surface ( like mine ). So far my attempts all failed because of that dreaded fact of being using a 4 yr laptop to play the game :/ In fact you probably need even less RCS in Kerbin than for doing that in the Mun or Minmus, since you can use the atmosphere to skim out most of the kinetic energy of the ship. You only need to wait for the ship to attain terminal velocity ( typically something around 130-140 m/s ) and then have nerves of steel for the suicidal burn ...

Just a clarification ( I assume this is implicit, but as it was not explicitly stated ): The ship you land must be the one that starts the landing process, right ? Detachments in between are allowed or not ( to jettison empty RCS tanks , for example ) ? And OFC, the ship has to be in one piece upon end of landing, right ( otherwise you just have to put enough tanks between you and the capsule ) ?