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ferram4

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Everything posted by ferram4

  1. ferram4
    @Weatherman159: The Boeing 747 takes off at between 70 - 80 m/s; the F-104 Starfighter landed at ~90 m/s. It sounds like (for supersonic jets) you've got the right landing speed already. If you're building something more U-2 styled then the solution is to take a longer landing approach. You need to give the air more time to slow down your plane before you try to put it on the ground. If you're coming down at a 20 degree angle you're not going to bleed off enough speed before you can land. @a.g.:Backward facing nodes create additional drag, although their need for streamlining decreases as the Mach number goes to infinity. Long story short, the pressure on the rearward face becomes equal to the ambient air pressure at Mach = Infinity, which doesn't add any drag. However, at lower Mach numbers it can add quite a bit of drag.
  2. ferram4
    @CaptainKorhonen: A TWR of 2.5 at launch is way too high. Try to lower the TWR to something like 1.2 - 1.4 at launch. The second problem is that if your CoM is that close to the back of the rocket then your payload doesn't weigh anything; whatever's underneath that fairing isn't contributing enough to the mass distribution of the rocket to balance out the fairing's contribution to the location of the CoD. If necessary, add dummy payload weight to be ditched with the payload fairings to balance it out. Finally, it's possible that the mod parts are not set up correctly; FAR uses the size of the attachnodes to calculate drag caused by the base of an engine, uncovered fuel tanks, etc. 0.625m parts use size 0, 1.25m parts use size 1, 2.5m parts use 2, 3.75 use 3, etc. If that isn't set up properly then the engine will not make the drag it is supposed to, shifting your CoD further forward than it is supposed to be. @verikosto: The best rocket engine to put on your rockets is whatever will just barely get it off the ground at launch. If you use something too powerful then you risk losing control of the rocket during launch.
  3. ferram4
    @Stinkypubes: You do realize that I'm more focused on the physics than the UI, right? If it bothers you that much, you can go into the source code provided with the download and change it yourself, but it's not a priority. I would like to update it though, but I haven't gone through mods that have GUIs that I like to find example code yet. @SchoredingersHat: I really don't know if I'd be able to handle the Hooligan Labs airships properly, especially since they don't seem to be all that realistic in terms of the payloads they can lift. They just strike me as incredibly cheap and I'm not going to put too much work into having realistic aerodynamics apply to a cheap mod. Trying to model the deployable heatshield as a wing is a definite no. Wouldn't act anywhere near that. The main problem is trying to come up with the code to handle the change in drag, lift and moment coefficients due to deployment. @ialdabaoth: Sure, go ahead. It'll probably come out better than anything I'd come up with.
  4. ferram4
    Well, then uninstall it. The windows start open by default.
  5. ferram4
    @SchroedingersHat: I honestly don't know what to do for that one. I haven't coded anything to work with that try of behavior yet. @Stinkypubes: Click the button at the top of the main window. That will minimize it to just the button.
  6. ferram4
    @foamyesque: If that's for the 3-man pod, then the last number should be a 2, not a 1.
  7. ferram4
    Is the attachnode size correct for the heatshield? If it isn't then the drag value will be much smaller than it should be.
  8. ferram4
    Define "nice and gentle landing." Most landings (in real life) take place at well below 1 m/s; keep in mind that if you're landing at ~10 m/s your vehicle is going to move from the top of a 3-story building to the ground in a second (possibly less, depending on the building). I mean, that is pretty fast for a rocket that is still partially filled with fuel, you'd expect something to break. Honestly, all of the parts in KSP are already amazingly good at taking impacts, so the problem is likely that you're coming down too hard. Take a breather, practice landing on the Mun with smaller landers and try to keep the vertical velocity as low as possible; then repeat that for the heavier Kethane miner you're sending down.
  9. ferram4
    You should check out the jet-powered cruise missile included with FAR; it uses body lift to stay in the air. Lifting bodies can be used, they're just less effective at lifting at subsonic speeds.
  10. ferram4
    @astropapi1: You should post pictures of your planes so we can figure out what the problem is. I suspect that you think that the CoL is where it should be, but it actually isn't. Also, the help windows (see the "?" on the GUI? those open windows with information) will help you understand what everything means. If your plane steers one way or the other on the runway, that means that your landing gear aren't staying straight; make sure that they are perfectly straight and aren't shifting at all during the ground roll. Use struts if necessary. If you need a lot of pitch-up trim to keep it level then that means that either your CoL is too far back, you don't have enough control surfaces, or your engines are helping to push the plane downwards.
  11. ferram4
    TV Aerospace, B9 Aerospace and pWings will all work correctly; I believe that Firespitter is also compatible. A quick way to check is to open the part.cfg for one of the wings in the mod and look to see if it has a "FARWingAerodynamicModel" or "FARControllableSurface" PartModule defined. I've heard people complain about both. If your planes and rockets are already aerodynamically stable, then you will find it easier; proper aerodynamics reduce the dV loses to orbit. If they aren't stable, then your rockets and planes will flip and you won't go to space. Generally, smaller payloads are easier to launch while larger payloads become a severe engineering challenge. Docking lots of parts together becomes important if you want to have anything truly gigantic in space. Yep! It's surprisingly robust given what a lot of the modders come up with. Depends on what you do; honestly, struts are more necessary to prevent KSP's "symmetrical parts don't have identical strengths" bug. You only have to worry about compatibility for wing parts, and most mods with those parts will advertise FAR-compatibility. Odds are, if you can find a mod, it is compatible with FAR. You'll only have to delete the FerramAerospaceResearch folder; the people who need to delete the Squad folder are people who are updating from 0.9.4 (not ModuleManager-powered) to 0.9.5 and 0.9.5.1 (ModuleManager-powered). You may want to make a copy of your KSP install for FAR, since sometimes the proper aerodynamics can get on people's nerves.
  12. ferram4
    Have you gone and edited the "title" field? That's the one that controls the name. Just look for "Turbojet Engine" or something like that and change it to "Turboramjet Engine." It's just a string in the config file. If you mean "I want a copy of FAR's modified engines to go along with the stock engines, here's what you do: Go into the parts folder. Make a copy of part.cfg; name it something like FARengine.cfg. In that new cfg, change the "name" field or else KSP will have an aneurism. Scroll down to the "ModuleEngines" section. Open up the FerramAerospaceResearch.cfg from the zip. Copy the thrust and velocity curve modifications. Find the "title" and "description" sections; change them to something unique. You'll essentially be doing manually what ModuleManager does, but creating a new part; by keeping the new config in the same folder as the old one you can avoid making copies of the textures and models (which is what B9 Aerospace does). Or, if you're feeling super-lazy: This link is to v0.9.4 if you don't have a copy of it saved; pull the correct part.cfg files out, rename them, put them in the proper folders and it'll have the same effect.
  13. ferram4
    Ah, I see what's wrong. You must have been behind on updating to the ModuleManager-based version of FAR, since you never followed the instructions stated in this post, relevant part quoted: Basically, you don't have the "stock" part.cfg files there anymore. If you backed up your Parts folder (as was suggested prior to the ModuleManager-based FAR release) then you can re-update from there. Otherwise, you'll have to go into the stock KSP.zip to get the relevant files. I think you might be able to use the patcher to "repair" KSP, which (I think) will restore the stock config files. TL;DR: The stock cfgs are not stock; you have not properly reverted them. Doing so will revert the engines to what they were. Also, the "ramjet" part is because the engines are capable of running up to ~Mach 5. Turbojets run out of thrust long before then due to the heat caused by compressibility effects. Adding ramjet in there is to try and justify this by indicating that it functions in the same way that the SR-71's engines functioned.
  14. ferram4
    @CaptainArbitrary: e, maxdeflect, MidChordSweep and TaperRatio don't change here. Just cut b_2 and MAC in half; b_2 measures the distance from the attachment point to the tip of the surface while MAC measures the average distance from the front to the back of the surface.
  15. ferram4
    @Clamps: The jet engines are tuned down because they are incredibly overpowered with drag reduced. There is no reason that a jet engine without afterburners should create as much thrust as a rocket engine. @DarthVader: FAR uses ModuleManager to overwrite the stock config files. You will not need to copy each config file, the plugin will do that for you. You should also look up how to merge folders on a Mac, since I'm assuming you don't know how to do that if you've resorted to manually moving each file for mods.
  16. ferram4
    I suspect the problem is that the nuclear engine you're using doesn't have its impact tolerance and strength increased enough for its increased size. Based on what I've seen, this is a problem caused by g-force spikes due to the nature of the numerical integration needed to simulate physics in KSP; you'll have to either reduce thrust, increase the strength of the part in its config file or use a lot of struts.
  17. ferram4
    You don't have a proper version of ModuleManager.dll, so the parameters for stock wings haven't been added. It is included in the GameData folder.
  18. ferram4
    @Carzum: MechJeb works off of the stock drag model, which is zeroed out for almost all parts (excepting parachutes) with FAR installed. So, long story short, MechJeb is wrong and everything is working as it should. If you don't believe that a large SRB pushing a tiny payload should be able to accomplish what it did with FAR installed then you're still too used to the stock drag model. I'd suggest you try looking at what the dV of that rocket is and figure out how high it would go if you only lost 300 - 500 m/s of dV to drag. @Klajan: It does increase RAM usage for each part on rockets, as well as using up some memory just by being installed. This is because more memory is needed to calculate the aerodynamic forces and to reduce computational overhead (by quite a bit; I'm storing the solutions to the equations here and here). I could look into some memory optimizations, but I don't know how much I'd be able to do.
  19. ferram4
    @grom: Based on my knowledge they are based on velocity and pressure. @ialdabaoth: I looked at that when the first versions of DRE came out, but didn't consider it too much of a priority. Also, I didn't understand the code initially and I like to have at least some basic understanding of exactly what's going on before I use the code. So maybe next update I can adjust this stuff.
  20. ferram4
    @SkyHook: If you still end up having problems, just post a pic of the rocket and the ascent profile you're using and we can figure it out. @grom: The mach effects and aerodynamic heating effects don't actually mean anything specific with FAR... they're just kinda there. Honestly, I'd love to hijack the mach effect and have it vary properly (only shows up near Mach 1, and very prominently) but they're just visual effects right now.
  21. ferram4
    @Delta Force: First, make sure that you've struted your wings up properly; there is a current KSP bug where parts placed with symmetry under the same load do not deflect the same amount. The second thing I'd do is make sure that your vertical stabilizer is perfectly straight; at very high dynamic pressures it can cause noticeable yaw and roll rates. Those should take care of the causes of a constant rolling moment. As for yaw stability, what it sounds you're really after is yaw damping; for this purpose what you're looking to do is maximize Sv * lv, where Sv is the area of the vertical tail and lv is the distance from the aerodynamic center of the vertical tail to the CoM of the plane. I hope you're not trying to turn the plane using the rudder. If you are, instead roll the plane and pull back to turn. Use the rudder for nothing more than countering adverse yaw (yawing in the opposite direction you intend to turn due to drag differences caused by deflected ailerons) and damping yaw motion. Keep in mind that as Mach number increases the lift slope near 0 AoA decreases (for very small angles, Cl = 4 * AoA * (M2 - 1)-0.5). So planes tend to get a little unstable in yaw as they speed up; you may be interested looking up the wedge tail of the X-15 since it also had yaw stability problems at high Mach numbers. @grom: Well, first you place control surfaces where you would like spoilers or flaps. Then you use the Editor GUI's control surface tab to set their functions and how much they deflect. Then you set what action groups you want the flaps to respond to; there is one command for increasing deflection and another for decreasing. Then, in flight, you use those action groups to control the flaps while the spoilers respond to brake inputs (which I should change to be an action group itself). @SkyHook: It sounds like you're building aerodynamically unstable rockets or taking a highly aggressive ascent profile that is not actually a gravity turn. You can try posting a picture and all of us here can try diagnosing the problem, but a good first step is to read the new suggestions section of the readme.txt, which has some basic suggestions.
  22. ferram4
    @Esulin: Don't even bother trying to use the calculator; with stock aerodynamics the drag force on each part varies with that part's mass, which means that the ship's mass can be ignored in the calculation. However, with FAR installed, this isn't the case. The calculator's assumptions do not match the physics being simulated with FAR, and no matter what you do you will not get a proper solution. @Bloodbunny: I'll need more info before I can go to work on it, especially since I haven't used that plugin. Without a log, I don't know where the source of the bug is. @foamyesque: Aerospikes might have slightly less drag, but they taper so much more than other engines that I doubt the difference is that much. FAR also detects if an attach node is buried in another part just to fix the problem you came up with. Basically, that's handled in the "is this unused?" section of the code.
  23. ferram4
    @Delta Force: Some of the effects of vortex drag are simulated, but on a canard like that they don't make much sense. Also, at supersonic speeds winglets really don't help at all. If you want an idea of how different wing shapes and locations affect airplane performance, start Google-ing information about aerodynamics; you'll quickly find information on how a wing's aspect ratio, taper ratio, sweep angle and such affect its lift and drag. @Kidneythump: If nothing shows up in the log, then it's probably just all the initial math that needs to be done to set up the aerodynamics combined with KSP loading the entire scene. If that's the case then you're not going to be able to get around it unless you consider waiting a few minutes "getting around it." @Van Disaster: I tried modelling ground effect a few releases ago; it wasn't noticeable at all. So I'm not bothering to reduce computational overhead.
  24. ferram4
    @Delta Force: It needs larger control surfaces; those are tiny relative to the wings and unmoving canards. Also, get rid of the little winglets on the canards, they really aren't helping with drag and they make your plane less stable in yaw. @MR4Y: Get rid of any unnecessary parts in your design; I've found that the key to building SpaceShipOne + White Knight vehicles is to try and reduce the number of parts as much as possible to reduce wobble. Try to get your spaceplane closer to the carrier vehicle so that you can get rid of the stilts it's on; that will help reduce wobble a bit. Also, try angling the carrier's wings so that the central fuselage is higher up for the same reasons.
  25. ferram4
    @Delta Force: You need to either move the CoM closer to the thrust vector or you need to use lifting surfaces to create enough of a pitching moment to balance the offset thrust vector. Or you need to reduce the thrust vector. You could try any of these solutions: Reduce the mass of the main fuselage to shift the CoM downwards towards the engines. Tilt the engines upwards to point them more towards the CoM. Add some positive camber near the back of your wing to help tilt the plane downwards. Add some negative angle of attack to your forward canard to do the same. Increase the size of the pitch control surfaces. Carefully regulate throttle to help maintain control. There's really nothing else you can do; the forces and moments must be balanced somehow.
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