[Stock Only] Single Launch Eve Landing/Return Mission

[r_rolo1]

Launch from sea-level would be the most impressive, but as stated above the challenge is hard enough as-is; using a high-altitude launch site is more than acceptable if you ask me. Plus it takes more skill to find and land at such a site.

Note that I'm not dissing his work. It is clear from his imgur album that he got a almost polar orbit on propose to get there and that alone requires some skill and a bunch of fuel even if you incline the orbit when you do the first aerobreak ( less than to get to 10 km from Eve surface from sea level though ). I was just stating that doing what he did going to 0m in Eve would almost surely require far more punch than the one he had available. Maybe to get to 0m in Eve and back without a ginourmous rocket we need to land in 11 km and then deploy a glider/plane to get to sea level and back ?

[Apotheosist]

I believe the challenge should remain as it is, although different categories could be implemented. I just did some tests with my Eve orbital ascent rocket, and I found that to get it up to a 10k apoapsis, took 5 of the 7 stages of my rocket. That's 100 tons out of 130. Which drasticaly reduces launch weight, and reduces the delta-v requirement from about 11500m/s to less than 8,000m/s.

[Excalibur]

Note that I'm not dissing his work. It is clear from his imgur album that he got a almost polar orbit on propose to get there and that alone requires some skill and a bunch of fuel even if you incline the orbit when you do the first aerobreak ( less than to get to 10 km from Eve surface from sea level though ). I was just stating that doing what he did going to 0m in Eve would almost surely require far more punch than the one he had available. Maybe to get to 0m in Eve and back without a ginourmous rocket we need to land in 11 km and then deploy a glider/plane to get to sea level and back ?

Never thought you were. Must say the competitive side of me rues the fact that someone else has beaten me to it! That said I was beginning to think this mission would be impossible, now we know for sure it isn't!

I do fear alas, that a large portion of success in this challenge depends on the power of your PC, such is the size of rockets required.

Edited September 28, 2012 by Excalibur

[nhnifong]

I do fear alas, that a large portion of success in this challenge depends on the power of you PC, such is the size of rockets required.

I'm using this challenge as justification for overclocking my CPU (even more)

[untitled]

Never thought you were. Must say the competitive side of me rues the fact that someone else has beaten me to it! That said I was beginning to think this mission would be impossible, now we know for sure it isn't!

I do fear alas, that a large portion of success in this challenge depends on the power of you PC, isuch is the size of rockets required.

I agree, the people that ultimately are capable of round tripping Eve are going to be those with the really high end computers.

In other news, only 250 m/s away from orbit!

[Excalibur]

I'm using this challenge as justification for overclocking my CPU (even more)

What CPU are you using? I've got an old Core2Quad Q6600 2.4GHz running at 3.6GHz on air, and it struggles with ships over 400 parts or so. I think I could get more out of it but my RAM is holding back the OC as my motherboard won't allow unlinked FSB ratios.

[nhnifong]

What CPU are you using? I've got an old Core2Quad Q6600 2.4GHz running at 3.6GHz on air, and it struggles with ships over 400 parts or so. I think I could get more out of it but my RAM is holding back the OC as my motherboard won't allow unlinked FSB ratios.

Core i5 2500K. The native clock speed is like 3.3 or something and I'm running it at 3.9 usually. With better cooling I should be able to take it up to 4.5

[Excalibur]

Core i5 2500K. The native clock speed is like 3.3 or something and I'm running it at 3.9 usually. With better cooling I should be able to take it up to 4.5

A good friend of mine had one of those; he did his research and sought one with the optimum stepping allowing him to reach over 5GHz on air. I think he stepped it down to about 4.6 for 24/7 operations. He held the record on the Overclockers.co.uk forums for that chip for a while...

[r_rolo1]

Never thought you were. Must say the competitive side of me rues the fact that someone else has beaten me to it! That said I was beginning to think this mission would be impossible, now we know for sure it isn't!

I do fear alas, that a large portion of success in this challenge depends on the power of your PC, such is the size of rockets required.

Well I do not care much for the "1st to" thing, I just want to do it the more efficient way And that includes the " less CPU meltdowns" part being myself playing in a 4 yrs laptop with some really low Hz Core Duo ( to the point I'm actually considering to start playing in my 10 yrs mono core desktop ( because KSP so far is mono core and as it was one of the last mono cores to get out, it should supplant my crappy laptop with ease in theory ) ). I gave a look to the reddit guy craft file and there is definitely room for improvement there ( not that his rocket is bad ), so I'll probably work in that direction ( that and try my .16 rockets that I made for Eve ... still had no time for that )

[boolybooly]

Yes he made the smart moves, the polar orbit departure is clever to help with catching Eve but not essential, the staging of the ascent rocket was optimal, dropping stacks in pairs and not in bunches of six and the landing site cut the size of craft he needed by at least half. Props to that pilot, makes me wonder why I was being such a dumbass... I think I was just fed up of stages not being ejected properly and colliding with the ship all the time so I wanted fewer separations.

Edited September 28, 2012 by boolybooly

[DEADBEEF]

The craft file I posted to reddit really has a terribly designed Kerbin ascent stage which was just thrown together in order to reliably (if not efficiently) lift a decent sized craft.

If I rejigged that to use an asparagus configuration it'd probably run with good enough framerate that it can be human piloted.

Also, on returning to Kerbin I had 200L of fuel left, which is a massive amount.

I'm pretty sure that the interplanetary stage and Eve lander/ascent stages are pretty optimal though. It took me a few iterations to finish up on that design.

If I have time at the weekend I'll redo the mission without mechjeb.

Mechjeb was only really used for the ascent and for attitude holding anyway.

I set most of the landing up manually be entering Eve in a polar orbit and waiting for it to swing by below me. The mesa I landed on covers a huge area and it'd be pretty easy to land there without any assistance.

The transfers were also pretty much done manually, mechjeb just provided accurate phase angles.

EDIT:

Oh yeah, I made an addon today which allows you to slow down the physics simulation. This gets rid of any framerate issues when piloting large ships, even on crummy haardware.

The source is [here].

Would using this mod be allowable, at least for the kerbin ascent stage?

Edited September 28, 2012 by DEADBEEF

[r_rolo1]

Good to have you here Makes easier to discuss things

I do think that your ascent stage could do with some rework, and not only on the fuel line configuration. You have two sets of the larger LVs and you have only one working at any time ... this means that , if you mounted the 1st liquid stage tanks laterally without the engines and let the 2nd liquid stage to use that fuel, you could save a good bunch of tons in engines. And with some creativity, extra fuel lines and tank repositioning, you could use the aerospikes of the lander stage as well since t0 until the activation of the nuke ones ( increasing the initial TWR quite a bunch ).

Neither of this alterations would make the ship more fly-able without mechanical help , but I'm pretty sure that they would increase seriously the fuel efficiency of the rocket as a whole.

[untitled]

Redesigned my lander - same initial mass, but now I can get into a 300kmx300km orbit around kerbin!

Hopefully that translates into a 100kmx100km orbit around Eve.

Update: I definitely think that returning from Eve (getting to escape velocity) will be impossible. I'm near getting orbital velocity, yet I believe I'm starting to reach KSP's limits physics-wise.

Edited September 29, 2012 by untitled

[melaus]

I accept your challenge and I raise you.

3 kerbal missions to eve and back, all stock except mechjeb. Its possible... barely.

http://melaus.imgur.com

[The Destroyer]

Holy. Crap.

[bsalis]

3 kerbal missions to eve and back, all stock except mechjeb. Its possible... barely.

2264.5 tons at launch. All asparagus staging?

So.. would you be the first player to do this?

[SpaceGibsy]

i did a single capsule flight yesterday.. ~420 tons.. ill post craft and doku soon

[melaus]

yeah, its all asparagus, 32 stages in all. I haven't seen anyone break the 2000 ton barrier before. It took a lot of trial and error. at that size even the smallest change would make the difference between flying and exploding on the launchpad.

[SpaceGibsy]

Can't hit the landingspot today - more pictures will follow.. let me present the Eve_M (Madness). Even if it's not 1/5 as mad than the 2xxx tons approach

The First two boosterstages are just mad an could be designed way less kerbal. The Eve-lander is actually near perfect - less than 42 tonns are enugh to get back to kerbin.

Using only 4 spikes, 1 Nuke and 4 Big ones its actually cpu-friendly..

[melaus]

Interesting ship. have you figured out if that thing can land on eve? that part looks... deadly.

[HYuy]

Managed to make a ship that meets the challenge. It can take off from Kerbin on it's own, fly to Eve, land, and get back into Eve Orbit. Sadly, it doesn't have enough power left in it to reach escape velocity and get back to Kerbin on it's own, and it's only a 1 man capsule. Originally did the mission over a week ago with advice from guys on the IRC channel, but I wanted to revise the early lifter stages to be more CPU-friendly.

The EVE Exodus Mk6

On the landing pad: http://i.imgur.com/s8bEK.jpg

On Eve's surface: http://i.imgur.com/n6PIh.jpg

Back in Eve's orbit: http://i.imgur.com/xR06p.jpg

(The Mk4 was the first to land and get back into orbit from Eve, but the Mk5 and Mk6 made the initial takeoff a lot easier)

[SpaceGibsy]

Interesting ship. have you figured out if that thing can land on eve? that part looks... deadly.

yes, it can land and return. landing is done by burning exactly 900m above an 11k+ hill using the stage right after "the big bag" that brings you on a collision course to eve. the 1200l fuel of that next stage are for both, targeting hill and powered landing.

[bloodgusher]

I just completed this under KSP 0.19, taking off from a 4700m plateau. Pics here:

http://imgur.com/a/D5x6F#0

The craft has plenty of delta-v to spare at each stage. The final eve ascent stage had 900 delta-v to spare, so it can probably launch from around 2500m given the right trajectory. Getting back to Kerbal under ion drive is slow but not terrible.

Yes, I used Mechjeb. I could manage without it except form the Eve landing retro burn. My reflexes are not fast enough for that one.

[Colonel_Panic]

First off, does anyone know the minimum delta-v requirement for taking off from an equatorial plateau on Eve?

This should be doable, and I will soon attempt it (and I swear to you I shall succeed) following the single-launch only rule. I'll get to explaining how in a moment, but first let's talk some theoreticals about this problem and how it could be done better outside the scope of our available parts.

Eve has a thick atmosphere lacking in oxygen so our available air-breathing engines are no good. However, it is combustible on its own, and should require only an oxidizer to make an eve-atmosphere-breathing engine... and if you use rocket fuel to power air-breathing engines for your kerbin ascent, you'll have oxidizer left over without needing to carry a bunch of extra fuel with you. This would change the equation to trivialize the delta-v problem and make it instead a problem of meticulous design and testing of spaceplanes for eve. There is not yet a stock part for this... but there should be. In fact, I would suggest to the developers if any are reading this, that the high-altitude low-efficiency jet engines in the game now should be able to operate on eve, using oxidizer as fuel instead of liquid fuel, while still operating on kerbin as they do now. From an engineering standpoint, such an engine would be possible to make, just wouldn't necessarily be as efficient. You could then with some smart engine and fuel management, do the round trip without a ton of weight.

Now, as for how to complete this challenge using only our currently available stock parts... I would question only one rule. If, it is acceptable to perform an orbital rendezvous during the mission, under the strict condition that it remain as a single launch (aka, you don't get to dock with anything you didn't bring with you in the first launch), then I would approach it as such:

1) design a staged eve ascent rocket that meets ONLY the bare minimum delta v requirement to get into low Eve orbit with an rcs tank, small docking port, and only minimal orbital maneuvering fuel to spare. most critical part: optimize the f*** out of this. Make it as small and lightweight as possible, getting no spare fuel into eve orbit. Do NOT bring an escape booster, or engine, only enough for the ascent and circularization of your orbit. Include a decoupler to drop the final stage and fuel tank, leaving only the pod and clamp-o-tron, maybe a solar panel.

2) design a lander stage, separate from the ascent stage. Use structural trusses to connect parachute and lander legs together into one detachable unit, which will act as a launch pad for the eve ascent rocket. Give it some small permanently attached fuel tanks and rockets for the deorbit and braking maneuver. You will leave the whole thing on the surface when you launch.

3) design an ejection and capture stage. This part is also critical to optimize. It should use asparagus staging of small fuel tanks around a single nuclear engine to provide enough delta-v to escape kerbin and reach eve with the lander and ascent booster, saving only one small tank of fuel. It should attach to the inverted lander via the clamp-o-tron on the capsule, using structural braces connecting to the lander frame. The second to last stage should have 2 additional nuclear engines to help with the kerbin escape burn carrying the lander. Also give this stage a couple radial parachutes near the top.

4) design a kerbin ascent stage capable of getting the whole thing into kerbin orbit. This part is a relatively straightforward brute force approach with asparagus staging. Use of excessive solid fuel boosters to clear the pad can't hurt either.

The mission:

1) ascend to kerbin orbit. If there is leftover fuel in the ascent booster, save it to assist in the ejection burn. Otherwise discard it while it's still on the edge of a suborbital trajectory to avoid putting the junk in orbit.

2) time your ejection burn. Stage off the fuel tanks as they empty to save weight. hit your aerobraking mark as early as possible once escaping kerbin's SOI.

3) fine tune your eve capture to hit an aerobraking mark that will put you in a very low orbit as close to a 90 degree orbital trajectory as possible. Use a second aerobraking maneuver to bring the apoapsis down further if it's too high, before circularizing.

4) decouple from the ejection and capture stage, leaving whatever's left of it it in orbit, and perform a retrograde burn with the lander, aiming for a plateau. Deploy your parachutes and lander legs as soon as is feasible. I hope you brought enough.

5) land on eve, find your pie tin, chill for a while basking in the purple haze. Smoke if you got em.

6) when the launch window comes around to return to kerbin, time your launch to rendezvous with the ejection and capture stage still in orbit.

7) dock with the ejection stage, and transfer all remaining fuel from your ascent booster into the ejection stage's remaining tank(s), then decouple from your ascent booster and fuel/rcs tanks.

8) perform your ejection burn. It should be easy with the 1 nuclear rocket and remaining fuel since you are carrying only your command pod.

9) plan a future mission to land a large capsule with THREE kerbals on eve and return for the next challenge.

Why this works: Your eve escape burn requires a ton of delta-v, and every ounce of weight you need to take back up into orbit from the surface will count against you tenfold in your ascent. By leaving your return fuel and rocket in orbit, you not only save the small amount of weight of carrying an extra booster from kerbin, but shave off 90% of the weight you need to carry back up from the Eve surface, and that will make all the difference in the world. As anyone can tell you: never move it twice if you only have to move it once.

I'm going to get started planning this mission soon, and I'm very confident in my ability to pull it off. I can already get THREE XL fuel tanks into kerbin orbit in a single launch, and that constitutes, as a single stage, 13,000+ delta-v with a nuclear engine. Staged properly, it's more than enough fuel to do the job. Wish me luck.

P.S., I don't care that I'm violating the letter of the rules as you laid out in the initial post. I'm thinking outside the box, and still adhering to them in spirit. It will be a single launch with no refueling stops. Trivial next to my mission to carry 4 SSTO spaceplanes, 2 rovers and 16 satellites to laythe at once and then return home with the lot of it like I was never there. http://cloud-2.steampowered.com/ugc/597003505302668172/DDF267A4244C6D5B8B613469B6BEE1DE01E277F8/

Edited May 12, 2013 by Colonel_Panic

[tavert]

Guys, this thread is 6 months old. There are a few threads about Eve that were created this year, you should do this discussion in one of those. Searching the forum a bit you should be able to find several examples of people's designs that have worked. Threads created this year will be a good indication they are referring to a recent version of the game, since Eve's surface was completely redone.