fommil

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About fommil

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  1. 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.
  2. 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.
  3. 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.
  4. 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
  5. 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?
  6. 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!
  7. 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!
  8. 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.
  9. 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.
  10. 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.
  11. 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!
  12. 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.
  13. 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
  14. just ONE twin-boar? wow, that's pretty awesome. You may well bow out, after taking the prize! I'm very interested in what you have to show here! To keep things simple, I always pick a solid booster that gets me to space, then burn horizontal with my stage 2. I keep reading about gravity turns but I've always found them to be more hassle than they are worth. I play career in Hard mode, so for me safety of the crew is more important than cost, so I've perhaps erred too much on the side of stable rockets that don't rely on aerodynamics too much. BTW, you might have missed my response to your design here:
  15. Awesome stuff! This is exactly the kind of thing I was hoping to see :-D I did a test flight and messed up my circularisation angles, but I got into 250km orbit to deliver 5872 units, giving an efficiency of 38.76... but I'm not counting the recovery costs of the earlier stages and of course this trajectory could be optimised. A few questions: how do you see how much you are recovering from parachutes on the earlier stages? I wonder if my solid boosters can survive an apoapsis of 70km... you don't have any RCS, so docking is... tricky you put your reaction wheels in a utility bay: why did you do that? I'm going to have to rethink my entire rocket design ethos... but at this scale of up-front cost, it might bankrupt me in Hard Career mode! (it'd be cheating for me to use your design, but I'll certainly learn from it)