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ferram4

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Everything posted by ferram4

  1. ferram4
    Well, there was the old Raycast Drag Experiment that I built for 0.19; I'll probably look into getting that working using the KSPAddon entry point instead of the ad hoc one I used before. That way there will be an answer for the aerodynamic equivalent of the, "we could model Lagrange points with a small SOI at each point," suggestion. But that doesn't count because it's mine. I don't begrudge people who come in here and yell at me about how things should or shouldn't work; there's always the possibility that they're right and I'm wrong. If they're right, I get to fix things and the mod gets better; if I'm right, they learn something. Either way, someone directly involved in the exchange benefits, while anyone looking in from the outside can also learn. And if none of that happens, it probably ends up being funny at least.
  2. ferram4
    @TeeGee: Alright, so what does this SSTO look like? And what counts as "high airspeed" during takeoff? 80 m/s? 120 m/s? 150? Have you tried adding flaps to your SSTO to give it a little extra lift? You're saying that you know how to fly planes with FAR, but you insist on putting your vehicle into a position where it has no room for error; if pitching it up a few degrees is enough to cause a flameout, then you're way to close to the flameout threshold. And it's true, KSP doesn't warn you about a flameout, which is why my plugin has a reading that you can use in one of the GUIs; I've been annoyed by this and thought of it already. Yeah, I know; I'm looking at ways to make the jets flameout more gracefully and evenly. There's no reason that the air from one side of the plane should be feeding the engine on the other side. That said, vertical stabilizers aren't as effective at high supersonic speeds; perhaps you need larger ones. Well, it's implemented is actually correct. The air intake and fuel consumption values point to it being the ratio for complete burning of Jet-A. When you're trying to run at full throttle with not enough air you're pouring too rich a mixture into the engine, interrupting combustion. Realistically, the engine control system should handle that for you, but this is KSP, where everything is done manually. The stock engines are tweaked to make less thrust with FAR; the air intakes provide the same amount of air and the same amount of drag. I don't see what you're complaining about, since you can fly much higher with FAR than in the stock game. I don't know about not getting to orbit easily; the stock Aeris 4A is easily capable of it with FAR. Why are you climbing until you reach 30km? Why not try to gain speed at 20km - 25km and then when the engines start to run out of breath pull up and not have to worry about switching over to rockets until 30km?
  3. ferram4
    Yeah... that sounds wrong. The center of pressure can end up outside the vessel, but I've never heard of the center of lift being outside it. I'll look into it.
  4. ferram4
    That's strange. The last time I've tested it it came down quite nicely. I can look into it more though. The CoL is just showing where the drag is being applied at that moment; angle it the other way and it will appear on the other side of the vessel, and at no angle of attack it should be directly below the capsule. What you're seeing is intended, but I think the way that the CoL is representing it is wrong (or at least unclear).
  5. ferram4
    @Surefoot; That's because in the previous version bodies made more lift than they should have at hypersonic speeds. That's been fixed now. @TeeGee: Well, you're installing something that changes the aerodynamics a lot, so that's to be expected. But here are some possible solutions: For taking off: If it simply won't pitch up, that means you need to move the landing gear forward or you need to increase your pitch authority--that can be accomplished with more control surfaces or moving the CoL closer to the CoM. If it does pitch up, but doesn't take off, then you need more lifting surfaces or you've got some type of interaction between the surfaces that is robbing them of lift--biplanes don't make twice the lift of monoplanes, they only make 1.1 - 1.2 times the lift, but twice the drag. For flying: Stop climbing to the highest altitude you can get away with immediately. The atmosphere isn't made of jello anymore, you don't need to be afraid of flying low with your intakes in no danger of flaming out. The Flight Data GUI has a nice little indicator showing how close you are to a flame out; perhaps that would be useful. Jet engines won't bring you to orbital velocity anymore; you need to light off rockets and hop out of the atmosphere instead of intake-spamming around the planet until you can spend 10 m/s to circularize. Yes, the design choices are somewhat limited with this mod, but complaining about that is like complaining that KSP limits you to having to attach engines at the bottom of your rocket; you can attach the engines anywhere else, but it will have very nasty consequences of doing so, either in wobbliness, control or Isp losses. Similarly, in FAR, you can build planes that look nothing like real planes that still fly, but there will be many adverse consequences to those design choices. You're complaining that your design actually influences your aerodynamics, rather than having almost no effect as in stock KSP. @asmi: If I recall correctly, the Soyuz decent module has its CoM in a very strange place; at least when I've used it I've always seen the camera act like the CoM is beneath the module itself. If that's not the cause, make sure that it's properly oriented when coming in, with the heat shield at a proper weight. If those aren't set properly, I can guarantee it won't behave like the real thing.
  6. ferram4
    Try tilting the tips of the rotor up, so that the rotor tips are above where they connect to the hub. The way it's currently set up, if it ends up off vertical the differences in blade angles will cause it to go further off of vertical. Tilting them the other way should cause it to remain stable. That said, this probably isn't going to work.
  7. ferram4
    @NathanKell: Alright, I'll look into both. No doubt I've caused something stupid to happen. @egreeSS: linSpring controls the stiffness of the spring that tries to bring the parts back together linDamp controls the strength of the damper that tries to counteract any movement caused by the spring / outside forces linLimit controls how much wiggle room there is before these particular values kick in linBounce determines whether the joint will "bounce" off the limit; so if it hits that limit and linBounce = 1, a force will be applied through the joint so that it will instantly go back in the other direction. Don't increase this, seriously. @KhaosCorp: What does the output_log.txt say is the source of the exception? I know that there is a similar issue in stock KSP where docking ports will not undock. @Surefoot: STOP BREAKING MY MOD! What exactly happened? Did it just start to jiggle around and then popped upwards? What's the output_log.txt say, if anything?
  8. ferram4
    @AdmiralTigerclaw: I suppose I could. Honestly, most of the stuff I've learned with aircraft design has used m/s everywhere, only dipping into other units for climb in ft/min, so it was never a priority for me. @evilphish, KerbMav and RavenColdheart: I've been planning to do that, but have held off on doing it because of how quickly the underlying code was changing; I'm not really in the mood to have to rewrite large parts of the manual at the same time. Probably have to include some stuff on basic aircraft and rocket aerodynamics for new players as well.
  9. ferram4
    Okay, version 0.10 is out. It includes a bunch of Editor GUI fixes by a.g., some work from sarbian to prepare for MJ compatibility, and the wonderful addition of proper modeling of command pod lift, so you can do proper lifting reentries now. More info in the changelog, which is in the readme.
  10. ferram4
    @a.g.: It's a known issue with working with discrete-time simulations. Basically, if the timestep isn't small enough the error in the simulation can add energy faster than the damper in the joint can remove it. The problem is that making the damper too strong can lead to things shaking themselves apart due to floating point errors. @NathanKell: Issue 1 sounds weird... how quickly does the game end up scaling down from 10 million, is it instantaneous or does it ramp? It might just be that physics is activating before the timewarp is "completed" and so things are breaking like they did in stock KSP a few versions ago. Does first coming down to a slower speed, then dropping out of timewarp fix it? With Issue 2, I'm gonna guess two other things are going on here: one is that you've got stretchy tanks installed for that Saturn IB; it seems like the huge masses and sizes of the stretchy tank parts causes lots of problems with whatever they're connected to. The second thing is that the launch clamps jump on load when this happens; it seems like RSS exacerbates a current issue with the clamps where they shift a little bit on load; it's somewhat intermittent though, so I don't know exactly what causes the shift to occur.
  11. ferram4
    I've still managed to summon the joint-Kraken with some of those radial attachments, so I don't consider it solved by any means. Go for a radial attachment with a lot of mass on the end of a long moment arm and you'll see it happen.
  12. ferram4
    @Starwaster: With FAR terminal velocity (for a fully fueled rocket) is supersonic at sea level--you'd have a lot of trouble getting above terminal velocity to begin with. If you are somehow capable of getting above terminal velocity with FAR, it means that you're bringing too much engine for your rocket. Going "slower" in the lower atmosphere with FAR basically means "don't outrun the control authority of your engine / don't let aerodynamic forces shred it." If you're using MFS with real fuels, I've found that a good just-barely-gets-to-orbit rocket is a modified form of the Kerbal X: Remove the landing legs from the orbiter; set the engine to use N2O2 and MMH; fill that tank with that blend. Take off the booster below that and put it to the side. Put an orange fuel tank below the orbiter stage and put a Skipper below that; set it to run on LH2 and LOX; fill the tank with that blend. Reattach the remainder of the stock Kerbal X below it; mess with the staging so it work right. To fly it, start to pitch over once it's going ~60 - 100 m/s; don't be afraid, its TWR shoots up once the asparagus boosters empty. Don't use SAS, and just make sure that it's pointing forward while in the atmosphere. @asmi: I agree; 7.5 km/s dV is needed for orbiting alone below ~300km; some extra must have been lost to gravity and drag.
  13. ferram4
    A.g. pointed that issue out to me shortly after I released v1.4; the v1.4.1 hotfix is up to fix that error, as well as an error where the max force a joint could apply was not handled properly.
  14. ferram4
    Alright, version 1.4 is up, which should hopefully fix most of the wobble people were having between parts of very different sizes. If not, there's always the config.xml to play with to see if that helps.
  15. ferram4
    @Surefoot: That's more of a KJR issue; probably best to discuss it in the KJR thread instead of here. Nevertheless, I'm looking into it. @KerbMav: Then KSP does not have proper write permissions and cannot save the config.xml file. @Frederf: Apparently moving the GUI so that the window is just below and to the right of the craft name textbox the button can shift underneath that box, hiding it and preventing you from opening the GUI. Just delete the config.xml buried down in the FAR folders and it should go back to working properly.
  16. ferram4
    @Captain_Party: Are there any other mods that you're using that might be causing that? Every launch I've seen done with this has the launch clamps properly attached to the ground.
  17. ferram4
    Is KSP not given proper write permissions in the directory it's in? If that's the case, then the config might not contain the proper values. An alternative is that you're repeatedly placing the GUI somewhere where it can't visibly load; it's there, but it's moved off the screen. What exactly do you do that causes this?
  18. ferram4
    @calkhi: Alright, here's what's happening: If your rockets are wobbling apart, it means that you're overspeeding, your TWR is too high, and your rocket is being destroyed by aerodynamic forces, like it would in reality. If your rockets are flipping out, it means that your rockets are producing more drag in front of the center of mass than at the back; you're trying to fly a lawn dart backwards, essentially; this also happens in reality. If the indicator is stalling on your rockets, it means that you hit a high enough angle of attack that one of the fins / control surfaces you stuck on started to suffer flow separation, like in reality. If you're pushing your rockets far off of prograde, they will suddenly suffer more severe aerodynamic forces, and possibly lose control, like in reality. If you're pulling a plane up to an angle of attack greater than 25 degrees, it's going to stall the second you do that, and then probably crash, like in reality. Honestly, your problems seem to be a combination of a failure to apply realistic aerodynamic principles to rocket and plane design as well as a large degree of pilot error. Honestly, it's to be expected, since stock KSP really punishes proper aerodynamic design and proper flight practices. You must unlearn what you have learned to fly realistic aerospace vehicles. Sorry to hear you're willing to give up so quickly though.
  19. ferram4
    You need to open it in notepad. Wordpad might corrupt it. Browsers won't let you do anything.
  20. ferram4
    I'll be honest that I'm not surprised that some mod parts don't play well with this, though I will look into fixing it. You guys can try looking into messing with the stiffness values in the config.xml to see if you can fix the issues; documentation is in the readme file. I believe some of the issues might come from how I'm treating surface attachments right now, which I plan to fix.
  21. ferram4
    @SFJackBauer: a.g. has been reworking a lot of the flight GUI to fix errors and make it more useful. He's also worked to make the CoL indicator more accurate, and all of his changes will be in the next release. @AdmiralTigerclaw: The configuration in the pictures should be sufficient. Doesn't B9 have larger landing gear though? Oh well, I'll figure it out.
  22. ferram4
    @Starwaster: I have managed to get bad code to cause something similar, where an infinite number of parts would be attached any time you tried to surface attach anything; normally it had to do with an exception being thrown in a function called by OnEditorAttach; I doubt it's the same issue though, since that tended to cause the editor to freeze and the game to crash due to RAM usage if it wasn't closed fast enough. Of course, none of this got into any of my releases, since it is literally game-breaking. @evilphish: You can probably work around the error with a single strut. If you manage to cause the issue again with other parts, say something so I can narrow down the source. @NicoH: I'll look into it; are there any particular combinations of parts that cause the issue?
  23. ferram4
    @AdmiralTigerclaw: You know what? Just post the craft and I'll take a look at it. No mods besides B9, correct? Worst case scenario I make some changes to increase drag. @velusip: That's a FAR debug line that I forgot to shut off; it'll be removed in the next release. @a.g.: It shouldn't be as dramatic as it is, but that should be a sort-of-stable configuration. The problem is the current version doesn't simulate the lift that should come from the air pressure on open attach nodes, only the drag; I'd originally had difficulty making command pods stable with that implemented, but I'm not sure exactly how I managed to fail at that, since the lift effect tends to bring the node to face directly into the flow. All that needs to happen now is for me to try and make sure that the potential and viscous lift of the rest of the body is correct and then, while this will still be possible, it won't be as... interesting.
  24. ferram4
    @Miller: That isn't a bug caused by KJR. That's an intermittent issue with Real Solar System's larger Kerbin and the Launch Clamps snap-to-ground functionality. @evilphish: I've noticed that one, and I'm not exactly sure what's causing it; part of me suspects that there's something weird with that in-line docking port, since that's the only one I've seen that happen with. @Damaske: Can you provide an output_log.txt after causing the issue? That honestly sounds like an error with some other mod, since KJR doesn't do anything in the editor (its code isn't set to load until the flight scene). Either KJR is doing something very, very wrong, or it's another mod causing your issue.
  25. ferram4
    @AdmiralTigerclaw: And how much thrust are the engines making while you're doing this? They're still quite a bit overpowered compared to real life, so thrust should easily overpower any drag you create. What flight path angle are you taking when you do this? It doesn't really matter how much drag you try to make with it, if it's aerodynamic enough to fly it will easily pick up speed even in a moderate descent. @BrickedKeyboard: That looks like it choked on figuring out the reference area; does the output_log.txt have any errors or exceptions in it? As for some actual answers: The procedural nose cones will reduce the drag compared to having a parallel setup without nose cones, but it will still make more drag than a purely vertical setup. The battery placement won't affect the total drag, but it might affect stability, since battery placement will affect where drag is applied. Making every stack equal heights will result in the vehicle being unstable due to all the drag at the top of it; shorter boosters will make our rocket less likely to flip out during flight. Honestly, that doesn't look like a basic rocket. It looks like you took a small asparagus rocket and just slapped nose cones on the top thinking that would solve all the aerodynamic issues you have to deal with now.
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