Laie

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About Laie

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  1. Throwing together a quick mock-up in the VAB, I see no way how to get there. Working assumption is that Rapiers shouldn't be burdened with more than 15t each, and that a single ion engine can be used for all the periapsis-kicking (out from Kerbin, down to and up from Tylo). It doesn't even get close.
  2. You're not alone, I'm having the same problem. The fairing sides seem to dislike lateral forces, I think -- it's more likely to happen on horizontal vessels, but a rocket shaking side-to-side on vessel load also tends to shed it's fairings. An issue on github exists by now. Me too. I know I've had some in a previous RO install but can't locate the package anymore.
  3. I know that 4600m/s for Tylo landing and ascent is quite tight. Do the other figures have a similarly small margin of error?
  4. A few points off the top of my head... for "realistic" you may want to: carry extra mass for life support have dedicated habitats for in space and on the surface generally, bring surface stuff to unpack and use plan for redundancy and abort modes like, lander can hover / move about for a bit (think apollo 11 and the debris field) landing may be aborted even at the last moment surface equipment is pre-deployed on a previous launch window bring two lifters, crew can fit into one if the other doesn't check out ... It's probably easiest to pick one of the existing mars proposals and try to follow it as good as you can.
  5. Docking ports problem

    Sounds like a stuck port to me. Have you undocked (one of) the ports previously? In that case they de-activate in oder to not immediately grab the port they've just been undocked from. They're supposed to become ready again once their previous dockee has been moved sufficiently far away (a few meters), but sometimes this doesn't happen. In the old days, one had to edit the savegame in order to fix this, but I think there's now a mod for that.
  6. TWR in a winged vessel..

    Nope, and nope. By assuming a prograde-only ascent I'm taking $directionOfProgradeAtAirbreatherShutdown as a given -- it should be possible to determine the required TWR mathematically from that (and velocity). Gravity losses also follow from these inputs. Having a higher-than-necessary TWR is not going to help anymore. Also, time-to-orbit is very nearly a moot point. All the energy-efficient ascents make you reach orbital velocity in the atmosphere with an AP somewhere on the far side, and require a lengthy coast at physics warp. But of course, that only means that $doPaAS is something worth looking into. I already alluded to the question in my last post: leaving the breathable air at a steeper angle will reduce the TWR you need to follow through. It will also reduce time-to-orbit (a little), and drag losses (because you "circularize" at, say, 50km rather than 35). This comes at the price of higher gravity losses and, probably more important, means you're not getting as much airspeed from your jets as you could on a shallower trajectory. @AeroGavI think, but cannot prove, that "maximum airspeed" is the wrong benchmark for how well you utilized your airbreathers. What you really want is not speed but something like (waves hands) "momentum you can take with you". A mere 1200m/s with a significant climb rate may be more useful for getting to space than 1600m/s in level flight. But alas, not only am I unable to provide a proper name, I also can't tell you how to make it comparable. Anyway, the engine question isn't strictly either-or. The Rapiers are already there, their dry mass bought and paid for, so the TWR is basically free. ISP notwithstanding, utilizing them to some degree is bound to be better than not using them at all. You don't need to run them all the way to orbit -- a 500m/s push will already help a great deal.
  7. TWR in a winged vessel..

    Hmmmm. I possibly should state my assumptions. Which I thought were so obvious that I needn't mention them, but then again that's how the worst misconceptions play out. So, I belive that the most efficient way to proceed to orbit after airbreather shutdown is "surface prograde" all the way, for minimum drag and maximum oberth. at the time rocketry takes over, "prograde" should be nearly level but with at least a hint of upwards. IMO a strong hint is better, but for this particular argument it doesn't really matter wether it's ten degrees or one tenth of a degree. On such a trajectory, you need the mostest (rocket) thrust at the time the airbreathers give up, and ever less as you proceed to orbit. I don't see how having a higher-than-necessary TWR would provide any benefit along the way. --- You can make do with a lower TWR if you're on a steeper ascent. Question now becomes, how steep can it be without under-utilizing the airbreathers?
  8. Miniature Refinery Troubles!

    Wanted to post that I never ran into the problem the OP describes, but now I know why. Seriously: if you want to run a proper refinery, use the big parts. The small parts are for building go-anywhere vessels, where you want to save mass. IMO, it makes perfect sense to only bring one drill (or perhaps two, for symmetry) and let time warp sort out the details. That's how I could run the setup without ever running into trouble. On high enough warp, I didn't even need to have enough power. Large drills would shut down when out of juice, but the small one would keep running -- I could operate the whole rig on a single RTG without issues, and on max warp it didn't even take very long.
  9. So I started dabbling with space stations and for planning purposes I'd like to have an exact copy of the station "as is" in VAB. I'm using KIS /KAS, so not all construction steps can be easily repeated in the editor, eat least not precisely. Is there a tool that can look at my savegame, puzzle together the vessel in it's current state, and create a loadable craft file?
  10. TWR in a winged vessel..

    The mistake is pitching to 20 degrees above prograde. You're missing the point: this wasn't a mistake but necessary. The low TWR forced all sorts of compromises, to the degree of not fully utilizing the airbreathers for speed because I needed upwards momentum. Still, for the plane in question it was a good solution. While the low-thrust, single nuke ascent wasted a lot of dV, adding the mass of another nuke would have cost even more. Or to put it the other way round: removing one nuke bought me a lot of dV, and the inefficient ascent didn't waste all of that. Ideal? Certainly not. But better and hence "more ideal" than increasing TWR by adding another engine. Well that's easy: you need the thrust at about the time when your airbreathers shut down or a little before, say, when they're positively starving. Required TWR then keeps decreasing the closer you get to a stable orbit. The better question is, how much of it do you need? This thread is exploring just how much TWR would be "ideal" and from my experience I'd guess that number to be pretty low, certainly less than 1 and possibly as small as 0.4, largely depending on how much extra engine mass would be needed to increase it. If your plane is based on Rapiers, you have more than enough thrust at your hands. ISP may be less than ideal but the mass is already bought and paid for; I'd say that in most cases you should just use it rather than slap on extra aerospikes or terriers or whatnot. Of these, only use as many as your mission requires (often that's not much at all) and run the rapiers as long as necessary to close the gap until the OMS can handle it alone.
  11. @1Revenger1: hey, thanks for tanking the time. I noticed too late that the 15km ceiling for supersonic had been lifted -- as it is, this plane was obsolete before it's first flight. I didn't expect it to be considered at all. The tall front wheel was copied from the Concorde (and is tame in comparison). On the screenshot, I notice you're flying with the cargo bay open, which probably explains some of the issues you've had. It holds a few control surfaces, toggles with landing gear, and is supposed to have the same effect as deployable canards would have. If you review other planes, check the craft description before rollout -- OP demanded such things to be noted there, which I have. No need to re-review this plane, though: As I said, it was built to meet requirements which have long been abandoned, and can't possibly compete with hypersonic cruisers zooming around at 30km. *giggles madly* -- don't I know it...
  12. This is great, easy, and hard to do right. Some newbie's early experience: I thought I'd use a winch as an umbilical cord, but found that I have to be close to adjust the length. Switching to the master vessel was impossible (presumably because my EVA'd Kerbal was part of the vessel?). Anyway, that umbilical cord did me no good. Trying to attach a part eventually worked, but keeping close enough on EVA is hard. Clearly, 3m is too short. I wanted to be smart-alecky and change it by MM rather than editing the config itself, but this didn't work: What is KISConfig if not a Module? Oh, and is there a way for a Kerbal to cling to a part and move it using the jetpack?
  13. What did you do in KSP today?

    @PT what's that cargo bay? It looks as if it might be procedural....
  14. What did you do in KSP today?

    For your particular problem: use the RCS only for attitude, and apply it gently enough so the reaction wheels can cope. Take your time. HOWTO: On your RCS: advanced tweakables -> show actuation toggles. Turn off pitch/yaw/roll. Then only use fine maneuvering (capslock on) and thrust carefully with SAS enabled. You'll quickly figure out how much thrust your wheels can take without torque-ing very much. I put overly strong reaction wheels on the tugs themselves for this very purpose. Sometimes it's necessary to disable them when there's no heavy load attached. If you can line up the tug with the CoM, you have one direction where you can thrust at leisure. This helps a lot. You can treat it as engines-only docking until you get close, and only have to tread carefully on the last few meters. If you have no earlier save to revert to, which is far and away the easiest solution, you may try to clean these "vessels" from the savegame manually.