The Eve Rocks Challenge (v0.90 only)

Remkeau · January 6, 2015

Here she is: my Eve ascent mission, boosting away from hell, escaping the clutches of the suffocating purple ball of death, doom and despair. Eh yes. For what? A rock! Anyway, here she goes: (apologies in advance for the post length and image heavy nature :rolleyes: )

- 3,323.31 ton and 806 parts on the pad.

- 292.75 ton and 326 parts on Eve in takeoff position

- Main ascent vehicle: 1,619,526 funds + 2x Tug: 1,006,268 = total ~3,632,062 funds

- 0.90

- mods used: KAC, KER, EVE (removed clouds on Eve itself at some point)

- Landing site was found through an advanced F5/F9 protocol and sheer luck. (only required 2 tries!)

In an alternate Kerbal universe, kerbals like to build tall rockets. Heck, the carnivorous ways of these Kerbals makes that they never even heard of Onions, Asparagus and that kind of veggie mumbojumbo. Hence, for an Eve return mission they shall use brute force, and low efficiency systems. This purple rock will look nice on the space program's managers desk as a presse-papier

The main mission report is in the following albums titles and descriptions. (Split into: - Getting to Eve, -De-orbit and landing, -The ascent and return)

This challenge really lived up to the term challenge. I spent many many hours designing and executing this mission. Just the transfer and landing phase took like 6 real world hours. Totally worth it though.

While finding the landing site was relatively easy to do, actually putting the Ascender down proved to be difficult. A tall rocket like this tends to snap into pieces when it hits even the slightest slope on the ground at pretty low speeds. My landing site was about 700 meters higher above sea level than my initial hyperedit trials. While this was great for Delta-V management, it turned out that my parachute configuration would not slow the craft down enough, even with the help of the 8 braking rockets. Pretty fireballs ensued to cleanse the soil. Countless quickloads later I used the help of the main engines to lower the touchdown speed to below 2,5 m/s. Luckily the fuel pods of the original brake rockets contained enough fuel to compensate for the fuel waste. Although the swaying movement after touchdown was still nerve wrecking. :sticktongue:

Landing on the tail! Check!

Another minor/major problem was the tug setup. If you rely on gimballing engines for tug control, never put them in a puller configuration it seems. I had to disable all gimballs and waste loads of RCS to get my setup to the place I needed it, and ended up wasting a lot of fuel again. (Hence the second tug sent immediately after the correction burns of the first)

I want to express gratitude to all the people posting here, your information was very valuable and inspiring.

Now! Onward to business, for a category 1 Eve Rocks attempt:

Getting there:

The descent and stuff:

The Ascent:

2001kraft · January 7, 2015

Nice job Remkeau!

Your design is one of the best ones here, and one that stands out too!

Sqwazare · January 7, 2015

Have added titles to the pictures to make it all a little bit clearer.

Second launch is the tanker, third the rover. The rover had its own launch as it was an afterthought between fueling up for the transfer and the transfer itself

kookoo_gr · January 8, 2015

I am thinking of doing this challenge. One question though, i have designed a lander that has 12000ish ÃŽâ€V and from the data i have form KER it can take off from Kerbin and get to Eve in one stage. Is this allowed, also if i make it to Eve can i send a refuel tank before landing, finally (so i can have more options, :sticktongue: ) can i refuel my lander once landed on Eve?

Laie · January 11, 2015

You're not allowed to create (mine, harvest) fuel on Eve, as this has been shown to be way too easy. But landing several vessels and transferring fuel between them will be perfectly alright.

- - - Updated - - -

I think it is. I don't see any parachutes or control surfaces, so this could have been Jebediah's level, but there's neither a picture nor explanation of the actual touchdown. Generally, there's lots of redundant pictures of maneuvering and transfer burns but some of the most interesting moments are not documented at all. I know how this happens, and am guilty of this myself, but looking at the pictures before and after the event...

As you descend through the atmosphere, I see four Rockomax-32 tanks on top of the outermost LFBs. In the first clear picture of the landed vessel, two of them are gone. I don't see any decouplers. What happened here?

- - - Updated - - -

Nevermind, that's actually a nice selection of pictures, and a good yarn to go with it. Eve sterilization procedure... <giggles>

My own rocket was only half as tall and already swaying dangerously, I can imagine how yours behaved. My keyboard would have bite marks if I tried your lander.

Congratulations, you've completed the Eve Rocks Challenge! Yours is one of those entries where I'm honestly sorry that I have nothing to give but a badge and some rep.

Sqwazare · January 11, 2015

The actual touchdown was very difficult and that is unfortunately why I failed to take any pictures of it as I was trying to keep my speed under control, as I felt I should be doing this manually and not leaving it to mechjeb. The 2 missing tanks were on the two LFB's that were broken off by the not quite as slow as it should have been touchdown, and exploded. If you would like some pictures of the touchdown, I can redo the landing in a similar area (Due to the enourmous size of this lander even mechjeb can't hit a pinpoint landing, as I have an on orbit save.

Alpheratz · January 11, 2015

Hi everyone,

This was more of a personal challenge, since Eve was the last body I had returned from. The design is very simple and the execution was sloppy, but I got it anyways. So here it is:

Starlionblue · January 14, 2015

I half-inadvertently asked myself if this can be done a week ago and have been trying ever since. I've managed to "land" on Eve three times so far but my vehicle has been so busted up that take-off was not an option. I'm sure I'm doing it wrong somehow. Probably a mite too heavy at 31000+ tons.

What I wanted to do for my Eve landing and return.

One vehicle only.
No refueling.
No docking.
3 Kerbals from the KSC to a landing on Eve and back to a landing on Kerbin.

Pics here.

I ended up with 2889 parts in 19 stages. 31290 tons on the pad, with delta-v of 17398, 21162 (atmo, vac). (File size is just around 4 megs.)

The biggest challenge design wise is the Eve lander and ascent vehicle. It has to be as light as possible so it can be hoisted into Kerbin orbit, but it also needs to have a delta-v of over 13000. The Kerbin launcher and transit stage is much simpler conceptually, but of course a vehicle that has to shoot almost 2700 tons from the KSC into low Kerbin Orbit and on to a encounter with Eve is going to present some challenges.

Asparagus staging makes the whole concept of a stage a bit blurry. As I see it though, I have two main stages, both of which use asparagus staging to toss bits as they go along. Sepratrons were essential to ensure the stacks separated cleanly. All those little fiddly bits led to a migraine-inducing staging sequence, especially if I had to troubleshoot.

Lower stage. Kerbin launch and transit. 28600 tons with delta-v of 6156, 6927 (atmo, vac). Asparagus with 6 branches. 121x S3 KS-25x4 engines. Each engine has a tank stack. The outer layer have taller stacks, maxing out at 3x Kerbodyne S3-14400 tanks plus 1x Kerbodyne S3-7200. The short stacks have 2x Kerbodyne S3-14400 on the inner layers. The "central stack group" of 1+6 have 4x Kerbodyne S3-14400 tanks. This central stack forms the transit stage.

Upper stage. Eve lander and ascent vehicle. 2690 tons with delta-v of 11242, 14235 (atmo, vac). Asparagus with 6 branches. 18x Kerbodyne KR-2L Advanced engines and 1x Rockomax "Skipper", each with one Kerbodyne S3-14400 tank. One additional set of 12 tanks without engines as an outer rim. The design is very wide and flat for stability when landing. The outer tanks are lower than the rest of the stack and have landing legs on the outer edge in order to keep the engine bells off the ground. 24 Mk16-XL chutes and 6 Mk25 drogue chutes. This lander could probably do a Duna landing and return mission from the KSP all by itself.

Flight observations

Launch was surprisingly stable. Fuel and oxidizer consumption is around 10600 and 13000 per second respectively. No need to worry about terminal velocity, as this monster doesn't accelerate very quickly. At 10000 meters the speed is only around 137m/s. At 15000 meters more than half the launch weight is already gone.

Getting to Low Kerbin Orbit takes around 8:30 minutes (including apoapsis burn). Once there, the lower stage has around 1650-1850 delta-v remaining. More than enough to get the lander to Eve if the launch window is favourable.

Decelerating at Eve is easy. Just aim for a periapsis of 55-60km and the atmosphere will drag you down. I had no fuel to waste on establishing orbit first anyway.

Landing on Eve. Now that is a challenge. My first two landers fell apart on splashdown. The third one almost made it onto solid ground but fell apart on touchdown. Heavy gravity is heavy! For my fourth attempt, I almost tripled the number of struts on the lander, adding many cross-connections between non-adjacent components. I also tripled the number of landing legs from 12 to 36.

Frame rate? Not awesome even with all graphics options set to the minimum. Before the first two stagings, I estimate frame rate at 1-2 fps. Every second of game time was around 15 seconds of real time. Game performance improved dramatically as boosters were shed. The lag meant there was no chance of steering manually. The only way to launch this vehicle is with MechJeb, either commanding Smart A.S.S. or autonomously with Ascent Guidance. Two other items which would have been very hard, perhaps even impossible, without MechJeb, were Delta-V calculations during construction and calculations for optimal interplanetary transfers.

Problems

Keeping everything organized. If you miss one or two bits and only notice when you're three layers further out in construction, the poor game performance on large builds makes things... hard... I forgot Sepratrons on the inner layers at first. Adding them was fiddly.
I forgot the fuel lines right in the middle of the lower stage but didn't discover my error until I tested the rocket. It was almost impossible to route them after that. I suppose I should have redone the whole thing from the inside out but I decided to accept the small decrease in delta-v due to the very middle bits not quite staging properly.
My vehicle was so large it filled up the VAB, often including the space "behind" the staging sequence interface. If that happens when you move a component in the staging sequence you also grab the "real" item behind it. I learned to scroll and zoom away from the vehicle after the first 500 mistakes or so...
Game performance. Even with all graphics options set to the minimim, once you go north of about 1500 parts things start crawling. One press of undo can take 30 seconds until you can dump the part. Crashes are also very common when going from VAB to the pad. These crashes often corrupt the craft file. I used an increasing number system for the files so that I didn't keep overwriting the same one. I also always backed the latest craft file up before pressing "launch".
I had one spectacular test failure where at 10000 meters the central core separated from the rest the outer layers. I'm guessing a combination of aerodynamic force and changing loads from the stacks. Spamming more struts fixed it. Systematic and significant cross-bracing is essential to ensure acceptable rigidity in such a complex structure.
Overheating. Limiting the throttle to 97-98% at launch kept temperatures under control. This throttle limit could then gradually be increased as altitude was gained and the rocket shrank.
Once the gravity turn started, difficulty in maintaining direction appeared. Winglets on the central stack, as well as locking the gimbals on 24 of the engines, limited this problem but did not eliminate it completely. Increasing rigidity with duct tape helped as well. More rigid vehicle means better directional control but this isn't really a problem except with large builds..
Once in orbit, control was very slow when not under power. I was also having big issues with electrical power. Adding a bunch of batteries and solar panels fixed the power issue. Tripling the number of vernor engines and relocating them to the ends of the stack made turning much easier. Still slow response though, which led to issues with auto-warp. MechJeb aligned the ship and turned on warp, but it would slowly lose alignment so I had to manually exit warp a few minutes before a maneuver to let it re-align.

Random thoughts

The first asparagus layers sheds at less than 1000 meters altitude. Those bits then fall to the ground and explode. Loudly. The first time I heard it I scrambled to figure out what was wrong with the stack.
Reaction control wheels seem to work better when centrally placed in the stack compared to at the ends.
On a vehicle this large, tripling up on batteries, solar panels, RCS thrusters and monopropellant tanks has a negligible effect on total delta-v, but it can save you a lot of headache.
18 large reaction control wheels use a lot of power.
When your Sepratrons aren't properly attached, they whizz away like spiraling fireworks, leaving you in a cold sweat hoping nothing will hit the main stack.
The VAB music is pretty grating after a few hours.
From the start of the project to a "landing" (crash) on Eve took at least 30 hours. A lot of that time was purely due to poor game performance once the number of parts increased. Not only does the assembly process take time, but you have to be very careful not to make any mistakes as fixing them is a pain.

Edited January 17, 2015 by Starlionblue

2001kraft · January 14, 2015

The person above just earned a rep for all that patience.

raygundan · January 16, 2015

Oh man, I don't know how I missed this thread-- I was building my Eve Missions right around the time this started! If it's not too late for a late submission, I'll toss mine in. It definitely satisfies the requirements for levels one and two. Whether it satisfies level three, I will leave up to the judges. It does take the entire lander to sea level and back-- but it does *not* launch from sea level. It must be driven to an altitude of around 6500m before launch. I will accept the decision either way, as it wasn't designed with this challenge in mind. I do feel that it meets the spirit of the requirement, however, in that it takes the entire lander, the kerbal, and the science equipment to sea level and back even if it does not use rockets to get from sea level to 6500m. Eve's lower atmosphere is like soup, but solar power is abundant. Using electric wheels for the first few thousand meters of ascent was just more efficient. I suppose an argument could be made that my "ascent" is actually when the drive from sea level begins... but again, it's your challenge.

The lifter is a straightforward two-stage asparagus-- the only real oddity here is that the center stack feeds forward to the transit stage, so that it can burn its engines during liftoff as well, giving us a substantial efficiency boost. The transit stage has both nukes and ion engines. The Eve lander section is a "reformatted" asparagus lifter with rover wheels-- literally the entire lander vehicle can be driven around. (And it was-- the lander was manually driven more than 200km on Eve's surface on this mission.) There is a separate vacuum lander can attached to the transit vehicle that can be used on small airless bodies. A third detachable unit, lifeboat pod with 4000m/s worth of ion dV, is also carried to help bail me out from screwups. The transit vehicle is spacious, with the vacuum lander can, a 4-man lander can, and the Eve lander pod.

The Heron II

Note: the forum gallery does a really awkward job with the imgur description text, letting it overlap the thumbnails to the point where you can't click on them. It is formatted much more cleanly if you just go directly to the writeup: http://imgur.com/a/owNWP.

To Sea Level on Eve and back, with a pod and a leave-behind science rover. I believe this was version 0.25. Weight on the launch pad was just 258t, all stock except MechJeb.

In addition to taking a science package, a kerbal, and a pod to sea level on Eve and returning them, the mission also carried a leave-behind remote science rover that stayed on Eve. Additionally, the mission landed on Gilly, made orbit around Duna, landed on Ike, and landed on Minmus before returning. Upon reaching Kerbin orbit, both parts of the transit vehicle and the vacuum lander were parked in orbit-- leaving a reusable 5-man habitat with multiple docking ports, a fuel tank, and two nuclear engines. It can serve as a space station or transit vehicle in future missions.

Flight writeup here:

http://imgur.com/a/owNWP

I believe *most* of the data requested in the challenge is provided in the writeup, but I'll return later this evening to edit this post and add anything that's missing.

Okay, filling in the data:

- weight and part count of the vessel on the launchpad

258.405t on the launchpad, exactly 500 parts

- weight and part count awaiting liftoff on Eve

24.1t, 182 parts

- the approximate price tag of your entire mission, if at all possible

$464,532 total price. Landed pieces may be recovered as well, but the all-in cost is just simpler.

- game version

0.25

- mods used

MechJeb

- tell me how you found your landing site. "I tried until I got lucky" is perfectly alright, but inquiring minds want to know.

The landing site was just a "near enough." The *takeoff* site, which is an entirely different matter, I found in a forum thread about the area where the tallest mountains on Eve were located. I don't think I hit precisely the tallest one, but I drove the lander/return vehicle for nearly six realtime hours across Eve looking for progressively taller places.

- if there's anything that your are especially proud of, be sure to point it out (provide a direct link to a picture if applicable).

It sends a Kerbal, a pod, a full science package, and a leave-behind remote-control rover to Eve with only 258t on the pad. I gave special attention to trying to make the whole thing look reasonably rocket-like. It's still an asparagus lander, but repackaged to fit vertically into the largest-diameter parts-- if we had fairings, it could have actually been enclosed. Despite the attempts to make the whole thing as light as possible, the kerbal has a spacious ship for the ride-- room for seven kerbals give him space to stretch out. And probably the proudest of all, it also landed on Gilly, Ike, and Minmus, made orbit around Duna, left a rover on Eve, and a space station at 300km around Kerbin. From a single 258t launch vehicle.

- please also mention the things that didn't work out so well / required a lot of saveloading / you would do different next time.

The biggest drawback is the use of a pod for ascent in this one. It's required for this challenge, but Eve itself doesn't seem to actually require it. A later version I built, the Egret, makes the trip with only 163t on the pad-- there is a pod for the Kerbal to ride in while driving around Eve, but as long as you're above about 5000m for your launch, the temperature on Eve is actually within the range a spacesuit can handle. So the pod is dropped on launch to lighten the fuel needed for return, which in turn makes *everything* lighter and easier to pilot. The kerbal is only exposed for the brief period during ascent from Eve, and I've verified that the temperature is within a spacesuit's tolerances during the entire brief flight. I like the Egret much better-- but its use of a chair for ascent probably disqualifies it, even if Jeb is in a pod for every other phase of the mission.

Edited January 18, 2015 by raygundan
Filling in missing information, adding proper gallery link

Kelderek · January 18, 2015

I made my first attempt at this challenge this week... and failed HARD, lol.

I spent several days designing, testing, flying, refueling, etc. -- all to no avail. I managed to place a 430t lander on Eve using parachutes, but the only way I could land safely was to burn some of my ascent stage fuel to soften the impact. Parachutes got me to 10.5 m/s which is enough to cause a beautiful explosion. Even a powered landing at 4 m/s blew up the whole ship. Finally got it to less than 2 m/s and came through intact. The problem was I had nowhere near enough fuel left to leave Eve and I doubt my lander could have done the job even with full tanks -- I'm pretty sure my design was doomed to fail.

So I basically rage quit by restoring to a previous quicksave and bringing Jeb, Bob and Bill back to Kerbin and I have abandoned the whole challeneg for now. I think I must need to learn a lot more and get more practice before I'll be able to pull this one off. This makes me all that more impressed by everyone here who has pulled it off successfully.

Question: Is there any kind of mod or debug hack that will allow me to either change the conditions on Kerbin to match those of Eve or to somehow warp my ship over to Eve's surface? I need a better way to test my ship designs. What works on Kerbin does not necessarily work on other worlds. I did use KER set to Eve in the VAB when designing my lander to get the DV values where I wanted, but I'm pretty sure that was not enough to get it right.

EDIT: also, poor performance makes this sort of challenge a lot less fun than it should be. I counted 6 seconds of real time go by for every 1 second of game time. My transfer burn to Eve was a nightmare since I could not manage to steer my ship straight with the amount of lag I had and the autopilot skills of Jeb using SAS did not work at all - I had to do it all manually to have any chance of controlling where I went.

Edited January 18, 2015 by Kelderek

redsh · January 18, 2015

You can use Hyperedit to test your craft right on Eve.

Also if you using landing legs, do not apply more than 5 tw per large stock leg and put enough chutes to limit landing speed to 10 m/s.

Edited January 18, 2015 by redsh

Starlionblue · January 18, 2015

In addition, the MechJeb Delta-V stats can be set to Eve (and elsewhere) so you get the TWR as if your rocket were operating there.

Sqwazare · January 18, 2015

Hi Laie,

hopefully this will give you the rest of the information you need for assessing my attempt.

Weight and Part count on Launch Pad -Lander Ã¢â‚¬â€œ 538 parts and 3,693 Tons

-Refuel Ã¢â‚¬â€œ 319 parts and 4,500 Tons, the other two weren't much

I needed an awful lot of fuel to haul my lander to Eve and be certain that I would have enough left to get back to orbit, given that I had never flown an Eve ascent. I had done a lot testing of other stages of the system but thought the ascent could wait for the actual mission.

Weight and part count on Eve pre liftoff Ã¢â‚¬â€œ 239 parts and 501 Tons. This was both lighter and fewer parts than planned as touchdown was a little hard, I broke off two LFBÃ¢â‚¬â„¢s and the X32 tanks that were on top of them, plus the 3 legs on each. Here I was very lucky as they were the first stage and not the second so I only lost what little dV they had left. Also due to the difficulty I had in executing the landing burn, and the concerns I had about whether I had landed on the correct slope I completely failed to take pictures of the landing. (I had done previous landings where the slope was wrong so Jeb couldnÃ¢â‚¬â„¢t get back onto his ladder, so I was fairly lax taking the pictures as I didnÃ¢â‚¬â„¢t know if this would be the final one) I also got distracted by the explosions of the X32 tanks when they detached.

Price tag for the mission as a whole would be in the order of 4.6 million, with very little if any fund recovery.

Version 0.90

Mods used Ã¢â‚¬â€œ MechJeb, KER, Hyperedit for testing various parts.

I found the landing site by reading through the forums for someone who had posted co-ordinates of a nearly flat nearly sea level point, as I had built in enough dV so I wanted to land at less than 100m. However one thing I discovered was that although MechJebs landing guidance can hit a fairly small target normally, when you are doing your deorbit burn in a 1000 Ton behemouth it isnÃ¢â‚¬â„¢t quite so precise so I couldnÃ¢â‚¬â„¢t hit the spot I had tested at, and as part of the testing was the ladder I hadnÃ¢â‚¬â„¢t thought a slight change in slope would put it out of reach.

What went wrong, I didnÃ¢â‚¬â„¢t test the rover at all and so had to ride around on the ladder as I didnÃ¢â‚¬â„¢t get them set up right, this also meant I lost out on a lot of science as I couldnÃ¢â‚¬â„¢t get it off the rover. I think it was my third attempt where my landing was on the right slope, and of course this was my worst landing, but it was enough, my first attempts were smoother with no broken parts. I would probably put on a lot more torque components on it; I was probably out by a factor of 5 for comfortable control. Also given the dV I had left I probably should have brought a second man and should have built something smaller and lighter.

Hopefully between this and my original submission it covers everything you would want except the landing pictures I failed to take

Laie · January 18, 2015

Sorry folks, my most recent Jool-5 has turned critical and that's where most of my KSP time went for this week. I will look at your entries REAL SOON NOW © . Promised.

Kelderek · January 18, 2015

Thanks for the tip about Hyperedit, I'll give that a try. The only mods I use so far are KER and a couple docking aids.

I used the parachute calculator which worked well, my landing speed with full chutes was 10.4 m/s. I had 8 drogue chutes, 16 of the big chutes, and 8 of the radial ones. On this mission I learned that it helps to stagger the chute deployment altitudes (something I never thought of before). I would have about 4 symmetrical chutes deploy around 1200m then 4 more at 1100, and so on down to about 900m. The first batch of chutes to deploy after the drogues were also the smallest, my 8 radial chutes so these had the least amount of jarring to the ship. All of this worked really well once I figured it out.

Based on what you're saying, I think my problem was the landing gear. I had 64 of the large ones and my ship is 430t that comes out to about 6.7t per leg which is why I had to add engine power to slow down a bit more.

Laie · January 18, 2015

I've given up on landing legs, at least on Eve. I suggest you try to build a contraption of structural parts (modular girders and the likes). I strongly suggest you try your contraption on Kerbin -- I had models that would jump and bounce, and thus could "walk" down a slope. If the slope is steep enough (not much needed) they can reach catastrophic speeds.

Landing on engines is not recommended: on the inevitable slopes you'll get a shear force ripping the engines from the tanks. That gave me a lot of trouble on my first design. The sole exception is the Liquid Fuel Booster -- its length means that the bad shear becomes a manageable bend. They will also withstand a 20m/s impact (though the rest of the vessel probably won't).

For testing, it's enough to put on launch clamps and release them so the lander drops on the launchpad (3-5m is usually enough; check max speed after the impact with F3). The pad will probably explode. If the lander survives and can stand on the rubble, it's worthy of further testing on Eve.

EdFred · January 18, 2015

Rather than MOAR Boosters, MOAR Legs

I had no buckling, crawling, or anything with my single man lander.

redsh · January 19, 2015

Remember that your craft weighs 430 t * 1.7 = 730 tw on Eve. So if you using legs, put about 140 of them. Slowing down isn't big deal imho, legs can absorb speed, static weight is more important.

I did not succeed to build custom legs that not walks on slope. For my 1600 t lander I found ideally flat area and precisely landed with MJ's autopilot.

Edited January 19, 2015 by redsh

Laie · January 19, 2015

Oh boy. Just a string of pictures without any comment, and no resource panel in sight anywhere. But then again, your mission was so straightforward that it needs no explaining, and I've seen enough similar designs that I trust yours. You may hang the badge from your signature, but I won't include you on the front page if you don't mind.

Edited January 20, 2015 by Laie

Right · January 22, 2015

Stats: http://i.imgur.com/KC0EvWJ.png
Total Cost: 330,451 C
Total Mass: 731t
Total Parts: 272
Mass awaiting liftoff on Eve: 134t
Parts awaiting liftoff on Eve: 212
Game version: 0.90
Mods used: MechJeb, Enhanced Navball,
Landing Note: Outside of landing during the day, it just took some trial and error.
The main thing I wish I had done differently was to secure the interplanetary stage to the Eve lifter better. It wobbled during burns. Edited January 24, 2015 by Right

Kelderek · January 23, 2015

Kelderek's Eve Rocks Submission

Objectives:

* Complete the Eve Rocks Challenge at level 3, "going all the way"

* Make the trip with at least Jeb, Bob and Bill present

* Succeed and fail simultaneously in different ways

* Outspend the competition to drive their economy to ruin

Design Philosophy:

* "Go big or go home"

* "Anything worth doing, is worth overdoing"

* Hide design flaws behind a sheer volume of vessel parts

* Use a single launch to help with vehicle stability (don't rely on docking ports to hold a ship together)

* Avoid refueling and using other vessels, mostly because I am lazy

Stats:

Vehicle on Kerbin launch pad (4 Kerbals on board):

11,566t mass

1818 parts

73.4m H x 29.4m W x 29.4m L

5,346,749 funds

Payload to LKO (lander + transfer stages):

1,660t mass

1,330 parts (roughly)

Lander on Eve's Surface:

1,056t mass

1,146 parts (roughly)

Game Data:

* Version 0.90

* Mods: KER, MechJeb, NavBall Docking Indicator, NavyFish DPAI

* All parts were stock excpet for the one little MechJeb thingy

Mission Imagery and Log:

(My apologies for the low texture quality, but minimum settings were required to let the game handle this huge ship)

Kerbin launch

Transfer to Eve

Landing on Eve

Ascending from Eve

Returning to Kerbin

Science archive proof that I really did get a "splashed down" sample and a "landed" sample since I forgot to grab a screenshot in the act of collecting the splashed one. You can see that they have the same title, but different descriptions.

Notes and Lessons Learned:

* There are probably a million things wrong with how I handled this mission, and as ugly as it was at times, I got it done in the end. I am still fairly new to the game (only a couple months so far) and I found this to be a considerable challenge to complete, so kudos to Laie for the idea.

* I've had a lot of trouble being able to fly large vessels comprised of smaller docked ships -- they just wobble way too much. For this reason I wanted to see if I could do this all in a single launch because it would allow me to have plenty of sturdy connections and struts for the entire journey.

* At some point I decided to avoid refueling in the spirit of "can I do without it?". This obviously meant I would need a far larger launch vehicle at the Kerbin pad. This snowballed into a test to see if my computer could handle the game and if the game would survive on its limited RAM (I use 32bit version of KSP). I knew that if I could get to LKO, then the rest of the way would be easier on my computer.

* The use of HyperEdit to test landing and ascent to and from Eve was a huge help, thanks to those who offered that up as a tip.

* The biggest mistakes I made were to not test every last part of all my various stages to their fullest. I tested the transfer stage the least and suffered as a result. I mainly made sure that the decouplers worked, but didn't do many actual flight tests or I would have discovered the need for much more RCS/torque. It took ages to make a simple 90 or 180 degree turn for manuever nodes. I had to assist it some with low thrust engine burns since those at least have gimbals.

* I tested my rovers a bunch and was happy with them on the ground. The only workable place to attach them to my vessel was on the sides, so I used two of them so they would be balanced symmetrically and in case one of them broke down somehow. The first time I tried this one of the rovers got caught up in the landing gear apparatus after decoupling. So I just decided to add a couple sepratrons with reduced fuel to push them away from the lander a little, but not too far. It completely slipped my mind that the speratrons would still be on the rovers afterward so I never tested the rovers after that - I only tested the decoupling to make sure they would fall clear of the lander and make it to the ground safely. As you can see from my images, the rovers ended up being useless due to how I had placed the sepratrons too close to the ladder rails. Of course it's good to know that in the future this type of design flaw won't be as catastrophic since Kerbals will be able to climb up on ledges.

* I had never used MechJeb prior to doing this challenge. I had avoided installing it because I worried that it would do too much of the work for me and dumb down the game too much. But I finally decided to give it a try because I knew that the ascent autopilot in particular would be helpful for getting off Eve. I used it sparingly at the early parts of the trip, but eventually tried out more and more of the features as I went along. When it comes to using mods, I usually prefer a minimalist approach for any game still in early acess or beta and I don't install many until after a game is released.

* I had trouble several times with my lander sitting on the ground at Eve wanting to rebalance every time I switched my focus away from it and back (like going back to the Space Center, or exiting the game and coming back). It acted like it had to land all over again and on a few occasions it would start wobbling and tear itself apart. I had to restore from quicksaves a couple of times to help the game remember that I had already achieved a safe and stable landing.

* I had to deal with several game crashes on this project, but they were confined mostly to the work with the entire launch rocket and its 1800+ part count. The most common crash was simply trying to load the rocket from the VAB to the launch pad. These were frustrating but did not happen often enough to slow me down in my fervor to complete this challenge. Also, there were never any crashes of the game after I staged the launch base at LKO - even though my ship was still 1300+ parts, apparently I was below some magical threshold for causing the game to crash.

Edited January 23, 2015 by Kelderek

parzr · January 23, 2015

that's AWESOME!

my lander is 1,200 tons and I'm going for jeb level and science level in the same trip. However, I've just gotten it alone into orbit with no staging and completely empty. Need to fuel it, transfer, land and ... You know... Do the mission.

Love your parachute solutions too I gave up on them for the weight of my lander.

Edited January 23, 2015 by parzr

Kelderek · January 23, 2015

@parzr: thanks!

I discovered on this mission that parachutes can be tough with a really heavy craft, they have a tendency to want to rip the ship apart when they deploy. My solution was to stagger the deployment altitudes in 100m increments from about 1400m down to 1000m, and since I used mostly radial parachutes (which are the smaller ones in size), they don't have a huge shock on the vessel when you only deploy a few at a time.

My test landings when using hyperedit had been at a different location with a higher altitude and I was pleasantly surprised that I could slow the ship down even more for the low altitude location I used on the mission. The air between sea level and about 1000m must be super-dense. It was also nice to find that I still had enough DV to make up for that altitude difference on the ascent too. The lowest I had tested the ship was around 600m I think and I did the mission at just over 200m.

Starlionblue · January 24, 2015

Staggering parachutes is definitely a must. However my Eve lander has to be strong enough to survive landing in Eve's gravity anyway so I have a ridiculous number of struts and landing legs.

BTW The KSP Parachute Calculator is extremely helpful for figuring out the number of chutes you need

Edited January 27, 2015 by Starlionblue

The Eve Rocks Challenge (v0.90 only)

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