Rescue mission to Eve

[Venerator]

I was about to attempt my first interplanetary mission to Duna yesterday, and I decided to have a test launch to make sure my rocket had enough power to get the upper stages into orbit. That was successful and I ended up just playing around with the maneuver nodes until I got to any planet just to get used to using the nuclear engines. I ended up landing on Eve (used loads more Delta V than I should have) but now I have three kerbals on Eve that I want to rescue.

I sent a rescue mission last night and got into orbit around Eve with loads of fuel to spare but realized I had nowhere near enough thrust or Delta V to Land and get back into Eve orbit... So I aborted the mission and sent the rescue ship back to kerbin. It's all been good practice, but I really want to get my kerbals home from Eve without just aborting the flight.

How am I going to get them home? I am pretty terrible with ship design so I have no idea where to begin building something that can get from Kerbin to Eve back to Eve orbit (if I could just get them into orbit I could send my old rescue ship to get close enough to EVA them into the hitchiker can).

Does anyone have any ideas on the best way to do this?

[KasperVld]

Eve ascends are pretty much the toughest things in the whole game, I'm afraid your Kerbals will be exposed to Eve's harsh conditions for a very long time..

[Atomictank]

Well there are several ways, you need roughly 13000-15000m/s to get into orbit and Eve has twice the gravity so make sure all of the stages of your accent vehicle have a TWR of well over 2. I reccomend using aero spikes and most likely cheaty parts.

[Promii]

You'll have to send a big ship with a separate (and extremely beefy) lander vehicle. Look around the forum for Eve landers, they're really big with lots of staging and usually use aerospikes because they do well in atmo. 3 Kerbals will require a heavy pod but fortunately you have another option now. Use a probe body and 3 rover seats or a 1-kerbal can and 2 seats to save mass. You'll need about 11500m/s Delta-v in the lander on the surface if they are at sea level. Eve is the most difficult planet to return to orbit from so I wish you luck.

[Kilmeister]

I'm sure your Kerbals will enjoy the pleasant trip through Eve's atmosphere strapped on the outside of the rockets

Something like this?

Edited May 30, 2013 by Kilmeister

[SOJUZ151]

my solution is that:

You are sending 280 tons of fuel to LKO with my rocket forum.kerbalspaceprogram.com/showthread.php/32110-super-heavy-refule-ship-280-tons-to-orbit

You are building some craft similar to eve starting stage from this video

but without nuclear engine , with remount control and 3 kerbal seats . Put it on top of some big rocket and mach all Aerospikes to one action group, add some rcs tank and docking ports at top of rocket.

Then fly it with big rocket to about 30km activate Aerospikes and get it to orbit .

Send small space station with some nuclear engines and dock it with return craft and big fuel ship in orbit . refuel return craft and fly to eve. When you arrive get on orbit and drop return craft to surface. you can separate rsc tanks and docking port. Take your kerbals back to orbit , get near to space station , then take them aboard the space station. Fly it to kerbin .

[Wait- Was That Important?]

Do not use a hitchhiker. The cost to bring any appreciable tonnage from Eve's surface at about sea level (where I assume your kerbals are) is horrendous, and the hitchhiker weighs 2.5 tons.

Here's my suggestion: build a two-part ship controlled with a probe core. The booster section should be rather large to push the weight of your lander, and have a hitchhiker module on it somewhere.

The second part is your lander- this will land near your stranded Kerbals and pick them up, and should also be remote controlled. It should use seats instead of a command pod, otherwise it'll be needlessly heavy.

Bring the kerbals up to orbit in the lander, dock with your boost section, transfer the kerbals and whatever fuel you have left, then fly back to Kerbin.

Good luck!

[Anglave]

My current personal project is to land a [stock] lander on Eve at sea level, and get it back to Kerbin again.

My best lander design so far employs a vertically staged spiral of radially mounted Aerospike engines. Each of the "legs" is a similar spiral of vertically staged Aerospikes. All engines (except the very top 909's) fire continuously until they're dropped. It sheds thrust and mass in a nearly perfect proportion.

It's approximately 280t, maintains a TWR of >1.2 on Eve, and packs just over 12,000m/s dV.

Any rescue mission that touches Eve's surface is going to require something similar. At a minimum. You could theoretically attach ladders to the final (orbital) stage, and have your victims rescued Kerbals cling to the outside.

I've pushed that lander to Kerbin orbit as payload, the lifter and lander being close to 1500 parts.

I've pushed it to Eve using a nuclear tug.

I've landed it softly on Eve near sea level, using the parachutes alone.

It's stable enough to make the ascent.

I'm nowhere near efficient enough on my manual ascent profile to make orbit from sea level on 12,000 m/s.

Edited May 30, 2013 by Anglave

[MarkusA380]

Use a plane for accent from eve. thats the easiest way to get away from the thick ath and the high g

[SOJUZ151]

Eve dont have oxygen in atmosphere so it wont work

[Anglave]

Use a plane for accent from eve. thats the easiest way to get away from the thick ath and the high g

I might refer you to this thread where the idea was discussed at length.

The consensus so far is that using a rocket plane on Eve isn't much advantage, if any. And would certainly take more parts and be more fragile than a standard vertical ascent.

Unless you've actually used a plane on Eve and can refute that conclusion from experience?

[Temstar]

I did a two men Eve landing and return mission using this 50 ton lander:

Capable of returning two guys to orbit if it landed at at least 5km altitude (highest peak on Eve is about 6.5km). I hear in 0.20 an EVA Kerbal now weigh three times as much (up from 32km to 90kg) so for the same lander to take up three guys some modification (or just landing at a higher altitude) may be required, but the basic idea is sound. Replace ladders with the seats.

Of course if you land the thing on a 6.5km mountain top you'll still need to drive your Kerbals to the lander, so you might also want to bring a rover on the same trip. Drop the rover separately from the rocket as close as possible to your downed crew. Get them to pile in and then drive to the lander.

The craft files are in that thread if you'll like to play with them.

[nhnifong]

Consider Firespitter's electric propellers. They're a godsend for Eve ascenders and air-travel. I've got a two-prop electric plane that can climb to 12 km on eve and has a top speed around 100 m/s.

[Colonel_Panic]

Okay, well, THREE kerbals will be hard to pull off, but it's doable.

Ditch the idea of taking them all up at once in a command pod though. It's far too much weight.

You need about 9000 delta v with over 2.0 Kerbin TWR to reach orbit from eve, assuming a high landing location. From sea level, expect a whopping 11,000! (Kerbin by comparison is closer to 4300 at 1.7TWR ). This will strain the law of diminishing returns, since anything below your fifth or sixth stage will only add on a tiny amount of delta v more.

Your lifter of choice will need to be asparagus staging with toroidal aerospikes, with a very light, high-delta-v final stage to get circularized. You'll want to have an LV-45 for your core stage engine to provide thrust vectoring on the ascent, and a 909 for the final stage. You will want to have an okto-2 probe core for your command part, and a piece of ladder for your kerbals to grab on to. Since they increased the weight of kerbals on EVA in the last update, I don't know how well this will work with all 3 at once. You may STILL need to take them one at a time.

Good luck. You're going to need it.