Ok, how do you land on Eve?

[juanml82]

And no smallish probes. I want something that land at least one Kerbal, have him take a surface sample and return it to Kerbin, so having him seated atop the rocket doesn't work either. Ideally, I also want to squeeze as much (useless) science as I can from the trip.

The problem is, every time I try to descend, something overheats and the chain reaction destroys the entire vessel.

Here's the ship I'm trying to land. I've tried it with hyperedit from an altitude of 2,600m and it can return to orbit, if I land it with full tanks.

There are heatshields beneath the external mk2 cockpits, which also detach before take off (from Eve). There are only there so kerbals can get to the ground and back.

I had attempted to use 8 airbrakes but they only seem to cook in the atmosphere, without adding significant drag.

Edited September 10, 2015 by juanml82

[cantab]

Eve entries are tough. The speeds are higher than at Kerbin and I believe the atmosphere doesn't tail off as neatly into space. A ship that big is going to be a real challenge to bring down fully fuelled. I can see three basic approaches:

Heatshield. You'll probably need to bodge one up using multiple smaller shields arranged together to protect the whole craft.

High-drag devices. You tried airbrakes but I think you'd really need to spam them. An alternative might be large wing panels, and "pancake" into the upper atmosphere shedding what speed you can, but getting to Eve in the first place with such wing panels probably won't be easy.

Refuel on the surface. Preferably using ISRU, but you could instead drop a series of smaller fuel vessels that can safely enter and land.

[Mister Dilsby]

I've landed a MK2 size spaceplane with no airbrakes or chutes, but not without some damage. For anything larger I recommend a powered re-entry--use your engines to keep under a speed that makes you blow up. If you do this, of course you will either need to bring LOTS of extra fuel or make more on the surface.

[Hagen von Tronje]

Airbrakes seem to work pretty great for me all things considered, the main problem is that they aren't going to be enough drag for the kind of titanic lifters that Eve demands to get back up. Good for orbital drops of cargo that won't be coming back up, maybe less good for what you have.

I managed to land a 1000t lander on Eve as a new player (don't interpret that to be skill, it was purely persistence outweighing common sense), and pretty much what I did was retroburn a whole lot. Like empty out the tanks retroburn. This didn't matter because I had ISRU, and it also didn't matter because it turned out the lander was in no way capable of ever leaving Eve again and the whole thing was a silly idea, but the point is that it landed with minimal exploderating.

If you can send down something with an ISRU unit and a claw (it would not need tanks of its own and could probably land with airbrakes and chutes only), and wheels so it can get up to the lander, you could use all the fuel you got retroburning into the atmosphere until you aren't catching fire, then deploy chutes for your happy landing. This means the only modifications to your design if it already launches is to decide if you need airbrakes or any of that other stuff anymore, so win/win! The catch is that you have to land the ISRU unit close enough to your lander that you are okay to drive it to the lander for refueling. Eve is hard to precision land on but easy to drive on if you ask me, so...might take a few tries but probably doable.

[juanml82]

High-drag devices. You tried airbrakes but I think you'd really need to spam them. An alternative might be large wing panels, and "pancake" into the upper atmosphere shedding what speed you can, but getting to Eve in the first place with such wing panels probably won't be easy.

Infernal Robotics

Now you see them in a low drag configuration

And now the hinge turns 90° and they work as large airbreaks. Even more, the fuel inside should be keeping them from overheating by adding thermal mass

This works. Or would have worked if my test vehicle hadn't landed on the Explodium Sea. Or if those wings wouldn't have collided and destroyed an mk3 to 2.5m adapter when I decoupled them because they seemed about to break away from the ship anyway. But it's definitely a doable concept.

As for ISRU, yes, it would help a lot. The problem is that I'm not finding a good way to put the hole thing in the same ship while designing it so I can get rid of the ISRU equipment before taking off from Eve and keeping it from overheating as well - the refinery has a 2000° K max temperature after all, and that's a close call during Eve's entry. And I don't feel like landing an ISRU rover nearby (if I manage that) and expending a lot of time driving across the terrain.

[MarvinKitFox]

I want something that land at least one Kerbal, have him take a surface sample and return it to Kerbin....

The problem is, every time I try to descend, something overheats and the chain reaction destroys the entire vessel.

If you are unable to get your rocket onto the surface of EVE, you are ***way*** unprepared to launch a return manned mission from Eve surface.

Trust me on this.

[tomf]

My plan was tyo land my rocket almost completlely empty and the land a rover nearby. The rover carries ISRU equipment and a claw so it drove up to the return vehicle, grabbed it with the claw and filled it up before retiring to a safe distance.

[Sharpy]

*shrug* delivered three rovers and a splashdown lander to Eve, ablator almost untouched. I really don't get people's problems.

The worst thing that happens is that OX-STATs break at 2m/s. Edited my save file two times to fix them, then began using hyperedit for electric charge.

[Warzouz]

No heatshield needed, nor airbrakes, nor drogues, nor chutes, nor engines : only Ker-balls

http://forum.kerbalspaceprogram.com/threads/130104-Survived-!

More seriously, I'm working on a Eve ascent vehicle too. I succesfully tested one for 180tons. I added lateral griders with landing struts (8 total) and airbrakes + drogue + chutes. These grides are ditched at takeoff. Those griders can be increased in size so the chutes stays quite high on the rocket. They also helps to have a wide landing base.

I noticed that Airbrakes are absolutely needed. not to slowdown but keep overheat under control. Atmosphere will slowdown surely, but will you survive the heat is anohter matter.

You can remove any drogues (even though, they can be open at 400m/s). Regular chutes can be open at 200m/s

My lander was largely overfueled (I ended with 2900m/s in LEO). I started to size it down (80 tons ?) but I never succeed ascending this smaller version du to instability at lift-off. Still working on that... I didn't choose the ISRU option because "my" Eve is very poor on Ore (average 1.2%).

[juanml82]

If you are unable to get your rocket onto the surface of EVE, you are ***way*** unprepared to launch a return manned mission from Eve surface.

Trust me on this.

I disagree, simply because I first tried to take off from Eve - and managed it - before trying to land those same ships and seeing them burn on reentry.

They are different issues. Taking off it's a matter of an aerodynamic shape, wings to keep it on course and enough mammoth engines. Surviving the reentry is a matter of heat and drag management. Getting the ship from the Launchpad to LKO might be a simpler matter of moar boosters while getting it to Eve can require refueling - which means docking, moar ships and probably an ISRU base.

- - - Updated - - -

More seriously, I'm working on a Eve ascent vehicle too. I succesfully tested one for 180tons. I added lateral griders with landing struts (8 total) and airbrakes + drogue + chutes. These grides are ditched at takeoff. Those griders can be increased in size so the chutes stays quite high on the rocket. They also helps to have a wide landing base.

The Mammoth engines have a 20 m/s impact resistance. My lander splashed down at 24 m/s, but maybe adding more chutes can be enough - or simply firing the rockets just before landing - to avoid landing legs altogether.

That is, if you're using Mammoth engines instead of aerospikes.

[Foxster]

You can make a small lifter for Eve, under 80t is quite do-able. This will go down easy with a few air brakes. But it won't get you back to Kerbin, so it means collecting the Kerbal and their science with a mother ship from Eve orbit.

Here's my latest stock sea-level to orbit capable craft that weighs in at just under 34t...

Edited September 10, 2015 by Foxster

[FlyingPete]

Apollo-style is the way to go I think. Otherwise, you're needlessly deorbiting and reorbiting the fuel for the return journey. Leave the fuel and engines in orbit of Eve and rendezvous the command pod with it.

- Launch the Eve lander and tug ship as two separate craft.

- Rendezvous the two craft in orbit of Kerbin

- Refuel the tanks as necessary.

- Use the tug's engines to send the combined craft to Eve

- Detach the lander and deorbit it with a Kerbal aboard.

- Collect rocks, plant a flag and other sciency things on the surface

- Launch the lander back into orbit

- Rendezvous with the tug in Eve orbit

- Optional: Go visit Gilly

- Bring the tug back to Kerbin.

[juanml82]

You can make a small lifter for Eve, under 80t is quite do-able. This will go down easy with a few air brakes. But it won't get you back to Kerbin, so it means collecting the Kerbal and their science with a mother ship from Eve orbit.

Here's my latest stock sea-level to orbit capable craft that weighs in at just under 34t...

http://i.imgur.com/IjlbKZR.jpg

Isn't the pancake design causing a lot of drag during ascend? Or am I worrying about aerodynamics for nothing? And what's the stuff you're clipping into the tanks?

[cantab]

Isn't the pancake design causing a lot of drag during ascend? Or am I worrying about aerodynamics for nothing? And what's the stuff you're clipping into the tanks?

Looking closely, I think he's put low drag devices, possibly air intakes, on the tanks then rotated them backwards. In newstock aero, and I think in old FAR too, that gives even less drag than a regularly-oriented nosecone.

[xtoro]

I've only landed a small probe so far, but seeing that rocket with wings made me think... Couldn't you have a rocket with wings that are attached via decouplers and glide down until you bleed off enough speed? You would just need to slow your vertical speed to keep from burning up... Then once you slow enough, depot chutes and decouple wings. So like, spaceplane going down, and rocket coming back up. I think I'm gonna give it a shot...

[technion]

This was pre 1.0, but I had FAR and DRE installed for a similar effect.

The short of it was I needed to use a combination of "using a rocket to bleed off speed" and "creative heat shield use". I can only see this working if your Eve ascender is as small as possible.

http://forum.kerbalspaceprogram.com/threads/82321-Eve-in-a-single-mission

[tbarcello]

You can make a small lifter for Eve, under 80t is quite do-able. This will go down easy with a few air brakes. But it won't get you back to Kerbin, so it means collecting the Kerbal and their science with a mother ship from Eve orbit.

Here's my latest stock sea-level to orbit capable craft that weighs in at just under 34t...

http://i.imgur.com/IjlbKZR.jpg

Dat ladder! Beauty!