Cheapest vessel to Eve!

[Wizard Kerbal]

To any kerbalnaut interested, 

Mortimer Kerman has a problem. He talked with Gene, and an Eve transfer window is coming up. However, the agency cannot afford a massive launch vehicle to put a single kerbalnaut on the surface and return with only a capsule.

He wants you to design the cheapest 1-launch vehicle to Eve. Simply have the most funds left over after a crewed Eve mission.

Details:

Get a moderate difficulty career save with commnet off and no cost required unlocking tech, maximize tech, facility and experience. Set your money to the maximum cost using the cheat menu, and build your vehicle(s). If you need more kerbonauts, there’s a cheat for that.

Maximum cost: 650,000
The vehicle can be recovered to recover funds. We’re not just asking for an extremely minimalist mission.

Mod & DLC friendly, just announce them and you’ll be put in another Leaderboard. Mechjeb, visual mods, and kerbal engineer will not be counted.

No ISRU/orbital refueling 

If you do any flybys/landings on other bodies, make sure to subtract the funds from those!

Points: 
Funds left +
Flag planted: 600 funds
Kerbal landed but left on Eve: 1,000 funds
Kerbal returned: 6,500 funds

My submission:
(Didn’t mean to press submit)

100% stock:
1. 647,850-QF9E
2. 
3. 

Modded/DLCs:
1. 
2.
3.

Badge:
Please put suggestions below, I really have no idea what it should look like.

Edited December 19, 2021 by Wizard Kerbal

[camacju]

ooh, this is interesting. I've been wanting to do something like this for a while now.

[QF9E]

Not sure if I fully understand the scoring. It is rather trivial to land a Kerbal on Eve, the difficult part is getting them back into Eve orbit. Do I understand you correctly that returning a Kerbal to Kerbin only nets you 1000 additional funds / points in the points tally? I don't think it is even possible to get a Kerbal from Eve's surface to Eve orbit for a mere 1000 funds, so if I understand the challenge correctly, just leaving the Kerbal on Eve's surface is the optimal strategy. Is that what you had in mind?

[Wizard Kerbal]

4 hours ago, QF9E said:

Not sure if I fully understand the scoring. It is rather trivial to land a Kerbal on Eve, the difficult part is getting them back into Eve orbit. Do I understand you correctly that returning a Kerbal to Kerbin only nets you 1000 additional funds / points in the points tally? I don't think it is even possible to get a Kerbal from Eve's surface to Eve orbit for a mere 1000 funds, so if I understand the challenge correctly, just leaving the Kerbal on Eve's surface is the optimal strategy. Is that what you had in mind?

Nope! I panicked when I didn't have it fully flushed out.

[camacju]

Maybe you could divide the challenge into three categories: Manned sample return, unmanned sample return, unmanned science transmission

[Wizard Kerbal]

5 hours ago, camacju said:

Maybe you could divide the challenge into three categories: Manned sample return, unmanned sample return, unmanned science transmission

It’s not the science I care for, it’s the kerbals.
And not even footprints, just getting there.

Edited December 18, 2021 by Wizard Kerbal

[QF9E]

On 12/18/2021 at 2:46 AM, Wizard Kerbal said:

It’s not the science I care for, it’s the kerbals.
And not even footprints, just getting there.

It is quite easy to get to Eve. In fact, landing on Eve is easier than landing on the Mun, as Eve's atmosphere does all the hard work for you. In contrast, getting back from Eve's surface to orbit is quite hard.

See https://imgur.com/a/afJG2gZ for a simple, non-returning, Kerballed mission to Eve.

 This rocket is all you need. I suspect an even cheaper rocket should be possible, I didn't take much time at all designing this one. A Thumper SRB as 1st stage, and an upper stage powered by a Terrier engine.

Landed on Eve, flag planted. Unfortunately, Jeb is now stuck here.

[camacju]

Working on an Eve return mission, here's a design of an Eve lander I had a couple iterations ago. Should be able to cut cost down a few hundred more funds

[Wizard Kerbal]

I feel ashamed with my 300,000 fund rocket

[QF9E]

8 hours ago, Wizard Kerbal said:

I feel ashamed with my 300,000 fund rocket

Don't be! KSP is a very hard game, the fact alone that you made it to Eve is an accomplishment. I think I saw a statistic somewhere that something in the order of 80% of KSP players never make it beyond Kerbin's SOI. I'm sorry I was a bit harsh in my previous comment.

[camacju]

Newest version of Eve lander. It's actually been pretty fun iterating the design further and further on this.

2889 kg, 7249 funds. I could probably save some more mass (and/or cost) by switching out the elevon 1 for elevon 4 (if the reduced control authority works), reworking the landing gear to use batteries or the elevons instead of the structural plates, and swapping a spider engine for an ant engine on the third stage.

[sevenperforce]

On 12/26/2021 at 1:50 PM, camacju said:

Newest version of Eve lander. It's actually been pretty fun iterating the design further and further on this.

2889 kg, 7249 funds. I could probably save some more mass (and/or cost) by switching out the elevon 1 for elevon 4 (if the reduced control authority works), reworking the landing gear to use batteries or the elevons instead of the structural plates, and swapping a spider engine for an ant engine on the third stage.

Is this kerbaled or no?

I got my kerballed Eve ascent vehicle down to 23k funds without much optimization but if you've got a Kerbal stuffed in there then I can't hope to compete.

[camacju]

5 hours ago, sevenperforce said:

Is this kerbaled or no?

Not only is it kerballed, it's a significantly older version of what I ended up doing. Here's the most recent version of the lander:

4378 funds, 1779 kg, not including kerbal. This can bring a kerbal from Eve sea level to low Eve orbit with about half of a jetpack remaining. This implies further room for both mass and cost reduction but I don't want to do that.

I actually abandoned the "lowest cost to Eve" mission in order to do a "lowest mass to Eve" mission. Turns out, a low cost Eve ascent vehicle tends to also be quite low mass. I got the total mass at launch down to 7.5 tons, which I believe is a record (that is, for missions that don't abuse aerodynamic bugs).

Here's the video I made about the minimal Eve mission:

Spoiler

 

 

[rmaine]

@camacjuNeat. I've never managed to get anything from Eve's surface to orbit at any cost or mass. I couldn't figure out what the vehicle was at all just from looking at the picture. The video clarified things a bit. Though I don't see the details of how you put it all together, I gather that the basic idea is that it is somehow helicoptering from Eve's surface up above the densest part of the atmosphere. Right?

[camacju]

Just now, rmaine said:

Though I don't see the details of how you put it all together, I gather that the basic idea is that it is somehow helicoptering from Eve's surface up above the densest part of the atmosphere. Right?

Yes, that's the basic idea.

For a bit more complex of an explanation:

The craft consists of four "stages." The first stage is powered by two small DLC rotors with a maximum size motor (you can probably get away with a smaller motor, saving mass and cost), each with eight basic fins rotated 20 degrees. Basic fins are great for an Eve helicopter because while they don't have a good top speed, they have much more wing area per mass and per fund than DLC propeller blades, and they don't fall off a cliff once their velocity passes Mach 1, meaning they can spin faster and generate more lift in the thin air. Additionally, centripetal force will pull the basic fins outward when the rotors spin up, meaning I can package the helicopter more conveniently and have it expand later. The ceiling of the helicopter stage is probably somewhere around 36 kilometers, but I found that detaching it at 35 kilometers is sufficient to get to orbit. It's powered by solar panels because it needs to ascend for a long time, and would require too much battery mass. The solar panels double as landing gear.

The second stage is powered by three Twitch engines, two Ant, and one Spider. It has a couple clipped Donut tanks and a Dumpling tank. This stage is also very aerodynamic due to the fairing, so it takes a steep ascent in order to leave Eve's atmosphere. It's still able to pick up a good amount of horizontal speed, however.

For the third stage, the Twitch engines and fairing are dropped, as well as all the drained fuel tanks and reaction wheel. I guess this is a stage and a half? No electrical systems whatsoever mean that the third stage must be controlled entirely through gimbal of the Spider engine, but I need more thrust than just the Spider, hence the Ant engines which have better vacuum efficiency. This stage is sufficient to get the kerbal almost to orbit.

The final stage makes use of the kerbal's EVA pack to finish circularizing the orbit and rendezvous with the return vehicle.

[BekfastDerp13]

*opens debug screen and teleports the command seat to eve and back to kerbin*

[sevenperforce]

13 hours ago, camacju said:

19 hours ago, sevenperforce said:

 

Not only is it kerballed, it's a significantly older version of what I ended up doing. Here's the most recent version of the lander:

4378 funds, 1779 kg, not including kerbal. This can bring a kerbal from Eve sea level to low Eve orbit with about half of a jetpack remaining. This implies further room for both mass and cost reduction but I don't want to do that.

I actually abandoned the "lowest cost to Eve" mission in order to do a "lowest mass to Eve" mission. Turns out, a low cost Eve ascent vehicle tends to also be quite low mass. I got the total mass at launch down to 7.5 tons, which I believe is a record (that is, for missions that don't abuse aerodynamic bugs).

Holy mackerel. That's truly exquisite.

[rmaine]

@camacju Aha. The "DLC rotor" bit explains one of my puzzlements. Presumably from Breaking Ground, which I don't have. I have Making History (and I use the important "missing history" mod), but I've never been much into ground operations, so I didn't bother to get Breaking Ground.

 

[Br0wnie007]

7 hours ago, rmaine said:

@camacju Aha. The "DLC rotor" bit explains one of my puzzlements. Presumably from Breaking Ground, which I don't have. I have Making History (and I use the important "missing history" mod), but I've never been much into ground operations, so I didn't bother to get Breaking Ground.

 

you should it adds rotors hinges pistons heillecopter blades the normal plane props, and more science equpment in my opion the rotors and hinges and pistons are geat for building gravity rings for interplantery ships and space stations