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Eve return possible in 1.0.4?


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Please forgive my noobiness if this is already answered and/or beating a dead horse. The fact of the matter is that I have been looking around and can't find any posts of Eve return missions in 1.0.4. The returning from Eve tutorial on the wiki was written in 2013 and does not seem to be viable anymore... Does anyone land on Eve anymore? If so, how do you get back?

Thanks,

Danny

Edited by CrashTestDanny
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I was preparing a mission and testing a lander using Hyperedit. I deorbited it with 9500 m/s, landed, and took off. Flight was fine and I ended in orbit (100km iirc) with 2900m/s left. This leans I did it with 6500m/s (starting from 1200m).

BUT I downsized the lander and failed with 7000m/s. Success with 7200m/s.

I never did the real mission though. I'm playing other game for now.

So yes it's possible and probably easier than in beta.

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I tried making something that get from the surface of Eve to low orbit. It lost the top nosecone from overheating, and had ~1300m/s delta-v left. Making sure the outer rockets didn't bump into the main rocket was hard too.

AA3B38DD87ED2F920420547B804F640F304A4DFC

It has a TWR of 1.6 and delta v of 5.3 and uses asparagus. Considering that it had 1.3km/s delta-v left it probably could've carried more to orbit, or went down with considerably less.

But generally you want to start out with MAXIMUM POWER and then sustain until the upper atmosphere where you return to MAXIMUM POWER

Edited by Mastikator
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There are a few people who have done it and posted videos to YouTube. I want to say that ShadowZone had a good video but I can't remember and I couldn't find the video I watched. With the introduction of ISRU in 1.0, an Eve return mission might be easier than it was previously although getting it down without burning up might be a bit more problematic.

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There are a few people who have done it and posted videos to YouTube. I want to say that ShadowZone had a good video but I can't remember and I couldn't find the video I watched. With the introduction of ISRU in 1.0, an Eve return mission might be easier than it was previously although getting it down without burning up might be a bit more problematic.

I think there is a weight threshold where you will have enough drag that you couldn't burn up if you tried. I think you might need to actual work to make it burn up on entry.

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From what I've seen, bigger rockets. I haven't actually returned with kerbals yet, but if you want to, go big.

Not necessarily. This stock craft will land and return to orbit from Eve sea level:

YJK7kul.jpg

Of course, you will need a mothership or a tug or something that can rendezvous with the capsule in Eve orbit to bring your man home.

Edited by Foxster
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A mothership in orbit is really not an issue. I'm kind of surprised though - the delta-V map I've been using has been very accurate so far, but it says 10k for an Eve orbit from surface, yet I seem to be hearing that it can be done for 5k by some, 7.2k by others, and in AstroBond's case, with a spaceplane whose CG burns aft of it's CL in the first 3 minutes of flight. I suppose if we use fuel balancer or maybe set up hoses to make the aft tank burn first, we can change that... hold my root beer while I try something...

Foxster - any chance of getting a better view of that ship?

Danny

Edited by CrashTestDanny
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A mothership in orbit is really not an issue. I'm kind of surprised though - the delta-V map I've been using has been very accurate so far, but it says 10k for an Eve orbit from surface, yet I seem to be hearing that it can be done for 5k by some, 7.2k by others, and in AstroBond's case, with a spaceplane whose CG burns aft of it's CL in the first 3 minutes of flight. I suppose if we use fuel balancer or maybe set up hoses to make the aft tank burn first, we can change that... hold my root beer while I try something...

I think most of the maps haven't been updated for the new aero model, and those that have been haven't necessarily been updated using the absolute optimal combination of lift/drag design. In any case, I think the answer to your OP question is a pretty clear "heck yes!" Good luck, maybe you can put your successful ascender in Mission Reports to inspire others :)

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A mothership in orbit is really not an issue. I'm kind of surprised though - the delta-V map I've been using has been very accurate so far, but it says 10k for an Eve orbit from surface, yet I seem to be hearing that it can be done for 5k by some, 7.2k by others, and in AstroBond's case, with a spaceplane whose CG burns aft of it's CL in the first 3 minutes of flight. I suppose if we use fuel balancer or maybe set up hoses to make the aft tank burn first, we can change that... hold my root beer while I try something...

Foxster - any chance of getting a better view of that ship?

Danny

One of the issues is that Eve's atmosphere is very soupy. You might have a craft with 10kdV that can't make orbit because it is draggy but a 7kdV craft will do it because it uses a few slim stacks.

It also depends where you land and lift from. Sea level is a fair bit more challenging than from the highest peak at 7.5km. Your lift flight profile is also going to make a big difference - if you drive through the soup for a long way at low altitude you are much less likely to make orbit and overheating will be a problem too.

Here's the craft file if you want to take it apart: https://www.dropbox.com/s/zosfe1lp529m30r/Eve%20new%20lifter%2069.craft?dl=0

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Eve landings require either mammoth or aerospike engines, probably a combination of both in heavier landers. The Mammoths have an impact resistance of 20 m/s, so if you're careful, you can avoid using landing legs/gear.

I think the biggest challenge now is heat, both during reentry and during ascend.

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Not necessarily. This stock craft will land and return to orbit from Eve sea level:

I'm having a hard time with that, for two reasons.

* Eve has to be the worst place ever to not have nosecones on the top of those tanks.

* That's not far off my current design.. and I've added a few more stages to make it successfully pull off the mission.

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I'm having a hard time with that, for two reasons.

* Eve has to be the worst place ever to not have nosecones on the top of those tanks.

* That's not far off my current design.. and I've added a few more stages to make it successfully pull off the mission.

I think he put inverted shock cones clipped into the tanks. Gamey, in my opinion, but KSP is a single player game after all.

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I think he put inverted shock cones clipped into the tanks. Gamey, in my opinion, but KSP is a single player game after all.

Yup and, as you say, a bit Gamey. However, it still makes orbit without doing that, it just leaves a tad more dV to play with in case the lift isn't spot on.

- - - Updated - - -

* That's not far off my current design.. and I've added a few more stages to make it successfully pull off the mission.

Not always the best strategy with Eve. The dV numbers might go up but so does the drag and it's that as much as anything that's made quite a few likely-looking Eve lifters fail.

A single mammoth is one way because you can build the ship in one streamlined stack. Aerospikes are the other, not only because they have a good SL TWR but also because they make for slim stacks.

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For about 10 days I've been working towards an Eve SSTO spaceplane with way-down-cargo capacity and space for up to 20 kerbs (since ascending is hard it'd be nice to only have to do it once for several descents and still bring everyone back, no?).

Using Astrobond's success as a model, launching from ~7km, following a similar flight profile, I'm still consistently coming up about 600m/s short. On paper, the dV/TWR/burn time specs are near-as-damnit identical, and based on testing the drag profile is close too.

I haven't given up yet, so there could be exciting news soon. Still, don't hold your breath :(

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I'm having a hard time with that, for two reasons.

* Eve has to be the worst place ever to not have nosecones on the top of those tanks.

* That's not far off my current design.. and I've added a few more stages to make it successfully pull off the mission.

Its been empircally tested that shock cones make the nest nose cones.

Its also been empirically tested that for some reason... all nose cones and such perform better if rotated 180 degrees.... although not be that much.

Its weird behavior, and I hope they change that... because I agree that it doesn't look right.

Also, I think the advanced nose cones should be at least as aerodynamic as the shock cone intakes....

but for the game in its current state, he's got the lowest drag nose cone set up possible (well, there's a case with inverted fairings that is even more exploity)

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The thing about intakes vs nosecones. Nosecones are there to push the air out of the way around the sides of the fuselage. Pushing air anywhere is basically drag, even if you're super-streamlined and hardly push it at all. Meanwhile, intakes are there to suck air into the fuselage, and not push it around at all. To put this in terms of pressure, a cone increases the air pressure in front, whereas an intake, due to airflow through the engine, creases low air pressure.

In KSP these effects are divided between the supersonic thrust increase seen in jet engines (IRL caused by slipstreaming airflow through the engine turbines) and the very low drag profiles of the intakes, but really the thrust increase should be directly tied to the intake and not the engine, and the low drag of the intakes should only apply if they're attached to the front of an engine nacelle, i.e. a hollow tube through which air will flow. The drag profile of a closed intake should be at least as high as that of a low-drag nosecone.

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Its been empircally tested that shock cones make the nest nose cones.

Its also been empirically tested that for some reason... all nose cones and such perform better if rotated 180 degrees.... although not be that much.

Well I can confirm it - I've used his craft and it's definitely capable of orbit. I had several failed attempts after I swapped for nosecones - but I won't argue if he says he's done it. It's certainly a great place to start though - so thanks Forster for putting that together! It also does surprisingly easily with the re-entry heat, so long as you do it gently.

I really prefer to this to the large mammoth type arrangement. Those huge landers just don't reflect my playstyle.

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Well, sounds like it's definitely possible... I have been working on adapting Astrobond's approach to a larger crew and cargo capacity with the idea of landing on Eve with a belly full of mining equipment, refilling fuel tanks and dropping the mining equipment and taking off with less cargo but more fuel than I came down with. So far what I am finding is that three pairs of BigS wings just isn't enough lift - even in Eve's dense air... :( But I'll keep at it...

I'll also try to make time this week to test the other craft that have been presented here... Many thanks for all the responses!

Danny

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