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oh, nice spot! I will try adding a bit of space and try some new designs. The irony is that I was trying to make it as small as possible to reduce the impact of the Eve gravity! ok, I'm starting to see the genius of your idea now!

that right there is the problem, though

found this video doing pretty much the same thing as me and the conclusion seems to be "save it and keep retrying until your wheels don't explode"

My usual trick is to attach a rover to a decoupler (or stack separator, or docking port) and set the release force to zero. I even put a little ledge below the rover so it doesn't fall too far, and use struts so that it doesn't suffer the impact of the release (let's be honest, it's never actually "zero" although I thought that was only going to be noticeable on low gravity planets). That works for me on Kerbin, Mun, Minmus, Duna, Gilly, Ike... But on Eve, my rover gets blasted around like crazy, and always ends up with broken wheels, even the ones with a high impact tolerance. Generally I find that decouple / releasing anything on Eve summons the Kraken. How do folk workaround this and get a rover onto Eve without all the exploding wheels? If there was an air bag, I'd use it!

Maybe it was already too late for me and I'd saved and reloaded, but time warp even when landed gives me explosions. I have to get to over 1km with an EVA before I can make my Kerbals do the time warp run.

nice hack! Unfortunately, time warp on Eve tends to summon the exploding Kraken.

a solid plan, thank you. Unfortunately, it didn't make any difference. I'm going to send a rescue party. What is more fun than 3 stranded kerbals and a broken spaceship? 3 stranded kerbals and 2 broken shapeships!

I think I got bit my the Kraken on Eve. I designed an ascent vehicle that was able to go from sealevel to orbit, tested many times with debug mode and "set position". But when I actually got the vehicle there, did my surface ops, and took off, it behaved very differently. The first stage is propellor based and I just didn't have the level of control that was designed in, stability was a really big problem. To test my sanity, I used the debug "set position" yet again with exactly the same craft (even down to the inventory of every kerbal and storage container) and checked every part and every resource (and especially to ensure raw/pitch/roll matched my design, because I needed to do some messing with that to get there), and the cheating craft still behaved as I previously tested but NOT as I was seeing with the real one. Is there any way to figure out what the Kraken did to my craft? I'm guessing it's offset some part during the landing (which is always brutal on Eve) in a way that isn't visible. Is this a known kind of Kraken attack? One small detail that gives me pause is that "control from here" on my pod and my docking port give exactly the same readout when switching between them normally. But in the landed craft, switching between them rotates the navball by a very slight amount. Suggesting something is out of place. Engineer EVA can rotate it slightly but the slight misalignment seems to be more fine grained than even the engineer can rotate.

oh wow, that explains it exactly! My intuition is for the lifter to be on a free moving gimbal, but of course it's a rigid body Reaction Wheels and Fins it is (at the bottom, which is a shame from a modularity point of view). Control surfaces don't seem to be needed, so maximum lift. I now have something that can get from the surface to 16.6k on fans, and from there to orbit with 3 Kerbals, most of the time. Margins are tight. Now all I have to do is figure out how to slow this thing down and land it. The 8 propellors at the top have more of an impact on CoM than I had originally invisioned. Lots of parachutes to pull the top up, I reckon.

Then getting to Eve then becomes the problem I've seen people put these inside cargo bays, but that's a step too far in terms of "exploiting Kerbal mechanics" for me. Heh, that'd be quite a lot of reaction wheels, but an option for sure!

thanks OHara. That's something I tried already but it didn't make much difference. However, I only tried it once... maybe I should do some more experiments with the propellors mounted on different locations. It's also possible that the counter-rotation setup I have is confusing the SAS. I am fairly sure I'm massively overspecced anyway with 8 spinny things. I can try with 4 (2 clockwise, 2 counterclockwise to avoid torque roll) just like a real quadcoptor.

Hi all, I'm designing an Eve return vehicle and I'm pretty sure I want my first stage to be an electric fan. I've got 4x radially mounted counter-propellors which each consist of a large motor (10% torque, didn't need any more), 81 inclination (optimised for lift, not speed), with 4 large turbine blades. It is able to lift double my expected payload mass at Kerbin sealevel so I expect to get to 15k-ish on Eve before having to dump it for boosters (currently testing that theory). 15k "for free" (1t of electric batteries, no flimsy solar panels) is pretty good going, I can get to orbit (cheating with the debug console) with 5.5k dv, instead of the oft-cited 8k. My question is: what is the best way to stabilise a low speed propellor lifter? Mine does not behave as I would intuitively expect, so the physics is clearly kerbal's wonky aero/lift model. What I would expect in real life is that I could put the propellors at the top of my lifter, like an amazon delivery drone. That should be very stable because the centre of mass is very far beneath the lift. However what actually happens is that it gets really unstable very quickly and I need to put 6x control surfaces at the bottom (even though I'm going super slow and they shouldn't control anything!), as if it were an unstable rocket. I also find that I get the most stability if I put the propellors near the center of mass like I was placing wings (which is super weird, in real life that'd be pretty silly). I'd really appreciate any explanations of how the propellors are modelled, if anybody is able to go into that kind of detail. I can add pictures later if there is interest.

This was during the transfer window. I think my problem is that I broke free of Kerbin THEN transferred. By doing it in a oner, it seems more efficient... same principle as trying to get into a high orbit perhaps. I'll believe the capture dv when I see it, I just can't see how it could be so low. Thanks all, I'll try again for my manned landing.

Hmm, I was breaking out of Kerbin and then plotting a rendezvous with Duna. I guess you have to use one of the cheating mods to be able to exploit the physics this much... is this the orbit multiplier one gets by being near a body? I still don't see how it's possible to turn that flyby into an orbit in such a small dv.

I think I need somebody to show me a flight that takes 130dv from Kerbin escape to Duna flyby before I'm willing to believe that.

It takes more like 1000dv to go to Duna once you've escaped Kerbin. It takes another 600dv more to turn a flyby into an orbit. What I see is more like what I see at https://alexmoon.github.io/ksp/#/Kerbin/1000/Duna/150/true/ballistic/false/8/143

I've known about the classic delta v map for a while, and I looked at it to plan a mission to Duna. It took me about 1000dv to go from Kerbin to a Duna flyby, whereas this claims it is 130dv. Luckily I discovered the error and did it all with waypoints instead. It was also a lot more than 130dv to go from flyby to (wide) orbit. Are the numbers wrong or am I reading it incorrectly?

Is it possible to siphon off some of the oxidiser that my jet engines are not using into an oxidiser tank? It would be great to be able to fill up the oxidiser tanks on the way up, burn them when the air runs out, then come back down (and not fill up the oxidiser anymore because it's not useful). Could result in super light spaceplanes!

I can't find any aerodynamic cones that are suitable for the front of a mk2 or mk3 spaceplane... what do people do? Always use a mk2 or mk3 cockpit? ah, there are fuel converters to std cone shapes... just need to flip them round. Ignore me!

only way I can see to improve on this would be to recover the solid stage shells, but they are moving too fast for parachutes to deploy so I'll need to tune the minimum pressure.

wow, ok, picking a cheaper probe core and getting the hang of the gravity turn (turning to 10 degrees straight away then following surface prograde, auto switching to orbital prograde) I'm getting 5895 to 250k orbit at an efficiency of $16/unit! This makes my design look like a hunk of junk. That Korolev cross is a pretty neat move! It is the game changer for using multiple stages in the atmosphere.

I think you just changed how I design rockets... a bit of practice with this gravity turn in sandbox mode and I might start swapping over my designs in career mode (where iterating this kind of thing is very expensive). Kinda cheating, but as long as I don't copy the `.craft` files I think it's fair enough Proves the value of R&D! oh, lol, the irony. My scientists on the Mun just finished giving me enough science points to build spaceplanes... but I'm sure this experiment in efficient fuel buses is not wasted.

Ah, ok... well I tried with just one row of solid boosters and igniting the twin boar on the launchpad. I got 3242 to 250k, giving an efficiency of $31/unit. Which is still far better than I was getting... but I don't know how you're getting almost half this. I probably held onto the solid booster shells for too long (they impact the twin boars if released when they are spent), and didn't gravity turn early enough. The impact on efficiency of the gravity turn is much higher than I had thought it would be. This certainly deserves further investigation... EDIT: I tried again with the gravity turn (and a really lucky disengagement of the solid boosters... that is the tricky bit) by turning to 10 degrees reasonably early on then tracking prograde once the solid boosters burnt out and I got down to $20/unit. That's pretty amazing!

I added a second row of boosters and that is much better... this is pretty neat! The twin boars can then kick in when the solid boosters burn out at about 20k. Are you maybe firing all engines from the launch pad? I had very little aerodynamic stability on the way up (I moved the reaction wheels to the top because it's weak in the middle, like in yours, but I have two instead of one) so my ascent was terrible. Nevertheless, I got 4488 units of liquid fuel to 250km round orbit at an efficiency of $28/unit! I'll try adding some aerodynamic stability to get that down to the teens that you're seeing. I'd never really appreciated the usefulness of the twin boar until now... I've opted for high space LSP and used the solid boosters to get me into space, completely ignoring atmospheric LSP.

Slashy, I built this rocket using the engines that you said in a later post, but it doesn't go anywhere for me: it doesn't have any stability on the way up, so I added two reaction wheels in the middle the solid boosters burn out at 3500m with a velocity of 150m/s the twin boar doesn't have enough TWR to take it up any higher did I misunderstand something in your design? Are you using any mods, like FAR? I'm using Kerbal 1.2.2