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Found 36 results

  1. Just wondering. Can you land using drag alone? Parachutes don't count here.
  2. EDIT - partially solved: although nothing ever shows as "shielded" in the debug menu (under fairings OR in cargo bays), parts properly stowed in STOCK cargo bays are showing no drag once the craft gets going. Looks like an issue of bays added in mods (as far as drag actually being applied to stowed parts). I don't know how to delete a post, but someone who can may want to knock this one out. ____________________________________________________________________________________________________________________________________________________________________ I posted this on the modded forum and got no replies, so I'm trying it here, as I've had the same problem on a brand new install as well. I've searched and cannot find why my cargo bays won't shield anything from drag. I've knocked out all the usual suspects I can find, and here's what I've done: 1. I've used different types of cargo bays, mk 2, all the mk 3s (and some OPT ones before my clean install) 2. NO clipping anywhere. 3. Internal parts attached to nodes inside cargo bay. 4. Tried different parts 5. No external parts attached to cargo bays except inline by external nodes. For testing used fuel tanks of same type as cargo bay attached to either end with one random tester part inside bay attached to internal node, nothing else but landing legs attached to fuel tanks and maybe a drone core attached to a fuel tank to allow actuation of bay doors. I load it up on the runway, look inside bay and parts (using debug menu) are showing NO for "shielded." Open and close bay doors, no difference. I haven't played the game in days because space planes are what I'm doing at this point, and useless cargo bays ruin space planes IMO. Please help?
  3. EDIT - partially solved: although nothing ever shows as "shielded" in the debug menu (under fairings OR in cargo bays), parts properly stowed in STOCK cargo bays are showing no drag once the craft gets going. Looks like an issue of bays added in mods (as far as drag actually being applied to stowed parts). I don't know how to delete a post, but someone who can may want to knock this one out. _____________________________________________________________________________________________________________________________________________ I've searched and cannot find why my cargo bays won't shield anything from drag. I've knocked out all the usual suspects I can find, and here's what I've done: 1. I've used different types of cargo bays, both stock and OPT. 2. NO clipping anywhere. 3. Internal parts attached to nodes inside cargo bay. 4. Tried different parts 5. No external parts attached to cargo bays except inline by external nodes. For testing used fuel tanks of same type as cargo bay attached to either end with one random tester part inside bay attached to internal node, nothing else but landing legs attached to fuel tanks and maybe a drone core attached to a fuel tank to allow actuation of bay doors. I load it up on the runway, look inside bay and parts (using debug menu) are showing NO for "shielded." Open and close bay doors, no difference. Used several types of different sized bays, mk3, mk2, OPT J, no difference. *(edit) I finally removed all mods and made a simple tester as described above and had the same results, but I will list my mods here anyways, since I put it in the modded category. xScience (doubtful) CommunityResourcePack (didn't install this? came with another mod?) Firespitter (didn't really want this one either...came with Infernal Robotics I think) InterstellarFuelSwitch Infernal Robotics MechJeb2 MechJeb2 Embedded by Dennis6492 OPT Planetshine (doubtful) TextureReplacerReplaced TweakScale Module Manager 2.8.0 I am running 1.3 with all mods updated and (I thought) working. I'm trying to get some space planes flying around and I use cargo bays extensively, so this issue is killing me. Any help would be very much appreciated!
  4. Hi, im wondering wether i should put all the solar panels for the Magnetoplasmadynamic's needs. Im considering overcovering the spaceplane with flat solar panels or just the typical Gigantors XL Would the plane oversuffer from drag if i overcover it with the flat solar panels?
  5. So I'm making a spaceplace in the 50-60 ton range, and I don't know what I did, but some relatively minor change now causes it to no longer go to space. I can't figure out what happened, but I think something is causing massive drag that shouldn't be, as it now feels sluggish and underpowered, and this is compared to another fairly similar spaceplane that's 15 tons heavier, with the same engines, it it goes to space just fine. Even worse, I just now forgot to retract the landing gear, and it still outperformed the lighter plane. So something's very wrong. I've tried to figure out what's causing the drag, but no luck. I'm not even sure if it's really drag, but it seems to be the most likely culprit. So far, I haven't any way to even see drag values. Supposedly MechJeb shows atmospheric drag, but I can't find that feature. And some other mods I tried were out of date. At any rate, this will only confirm if drag is the issue, not what part is causing it. Any ideas? Any suggestions to see the drag of parts?
  6. I am playing KSP with a bunch of mods. the game was running fine and then i had a game crash. i had to re validate, update my drivers and restart my computer to be able to get KSP to load again. when it did finally load and i tried to launch a plane from my hangar but i was unable to lift off as my speed couldn't go above 13m/s. i know it was working before because i had no problem gaining speed and flying with the exact same plane i was using. i thought it could just be the liquid engines but when i loaded up my rocket fueled plane it had the same effect. i could not gain speed its as if the physics had been changed by a mod or something was affecting the atmosphere. i tried deleting my physics file and re validating but that didn't fix it either. i opened the console config with shift F12 or w/e it is and looked up the default values online and the numbers were the same? any ideas on what could be causing these physic issues? or mods that might tamper with physics? i dont have the real physics mod installed thanks
  7. I've always hated the way drag is shown in stock KSP. I have no idea which parts are causing the most drag, and by how much. All i get are a bunch of long red lines overlapping each other so they are impossible to distinguish from one another. Is there a mod that changes the way drag is shown in the aero forces overlay view? I'm looking for something stock compatible that's not going to actually change drag, but just show it easier. Thanks in advance!
  8. Ladder Drag Cube Occlusion

    So, I'm not sure if anyone else has noticed this, but ladders have a ridiculous amount of drag. I've had them create as much drag as a Big-S Shuttle Wing on some occasions. Now, is there any nice way to make drag cubes check for other drag cubes existing in the same space, or would this be an absolute nightmare for anyone to code? I don't know a thing about modding on KSP, so I am posting this as a request, but if anyone knows some of the basics on how to do this, I'd be willing to try my hand at it.
  9. Hello, I was wondering if the parts that are radially attached inside the Mk1 Structural Fuselage are dragless and protected from reentry heat. I've noticed that with angle snap off, you can radially attach parts inside the fuselage, but when doing a reentry, things inside were showing temp gauges and some of them were destroyed. Do I need to use the fairings for that? Or was it that the fuselage was getting heated up(and resisting it fine) but passing that heat by conduction to the parts inside?
  10. I was playing ksp coming from minmus, but on re-entry, something wired happened. It refused to simulate drag. The spacecraft was at 900 m/s and accelerating at 2 km. Therefore, I couldn't deploy the parachutes.. Anybody else have this problem?
  11. It'll be really helpful to know the Lift&Drag characteristics on altitude and speed, to fly a proplane. Anyone knows something about this?
  12. Hello! I was designing a new prop. plane, which included a structural component(small cubic one) to hold a engine. So it files, but there seems to be one problem: speed. (It can't beat 50~60m/s ) I know that proplanes can't have very fast speed. The problem is, there is similar proplane I made which is much more faster. this one seems to be slower even with bigger thrust. The only differences I saw was: 1. The slower one used structural component to hold engines. 2. The slower one has bigger wings for prop. engine, which might have bigger drag. 3. The slower one has shorter cone, which would be more draggy. So how can I reduce drag in this situation? Are there some great techniques to reduce drag? If there is, please let me know and it'll be greatly appreciated! + Also I'd like to know which structural part with node attachment? This is necessary to offset parts far enough.
  13. Well, after hours of testing, reading, and testing again, I am still having a really hard time understanding the aerodynamics. Previous post: Even though my previous post was ironically the only ground drag issue that came into the equation with trying to make a stable jet, I'm still trying to build a stable jet. Rather, understanding how to make one that is. I know CoM, CoT, and CoL, but I don't understand their results. There are numerous claims that if the CoL is behind the CoM, then the rocket will be stable. KSP wiki: http://wiki.kerbalspaceprogram.com/wiki/Center_of_lift#Flight_characteristics foamyesque: But my mind is vehemently refusing to accept this. Don't you guys mean the "center of drag"? I feel like this is very similar to the CoL, but is still different. You could have a ship with two wings in the front and then a bunch of random parts on the back, and would fly with the drag-inducing parts in the back like an arrow with feathers. Yet, the CoL would be right between the two wings, because they are the only things providing lift. I've had planes where the CoL is significantly behind the CoM, but it still wants to flip at high speeds, or at least doesn't want to just go straight. And this flows into my second question. You know, let's make a list. Welcome to the buffet of questions for all your answering needs: Is the CoL the same thing as the "Center of Drag"? If not, is there a good way to find how far the CoD (center of drag) is behind the CoM? I've been shooting my crafts way up in the atmosphere and then letting them fall to see if the CoD is behind the CoM. Kinda time-consuming. If all parts create lift (KSP wiki quote below), why don't they change the CoL in-game? KSP wiki: http://wiki.kerbalspaceprogram.com/wiki/Lift#Dynamics The wings are symmetrical. Do they still produce vertical lift in ksp if they are not given any angle of attack? Are there specific wings that do/don't produce vertical lift at 0° angle of attack? I'm really sorry I'm asking the same question that everyone always asks, but this is a little different. Thank you so much for taking the time - Spemble
  14. With 1.2, drag is (even more) king and nosecones dictate that to a large degree. Since the Mk.3 Cockpit is the best command pod for reaction wheels, crew capacity, etc, I try to use it as often as possible. Thus: What nosecone is the least draggy while still being somewhat sane, functional, possibly even nice-looking? This is the best I could come up with: 1.25m Fairing clipped slightly into the Mk.3 pod. 2600 Max Temp (seems to be the highest of anything besides the pod itself)
  15. I have this spaceplane built in the previous versions, which doubles as a reasonable lander And it used to make it to orbit with plenty of dV to spare. I've just loaded it in 1.2.1 though and the rapiers can't keep up the thrust when they are breaking the sound barrier: They'll hold up to about match 1, but between match 1 and match 1.1 they will consistently keep loosing thrust, even if I level out or even descend slowly, which keeps me stuck below match 1.2. I've tried placing precoolers in front of the engines, but they don't change performance. I've replaced the front of the spaceplane with the MK2 (not inline) cockpit and while there is a thrust loss, it isn't nearly as pronounced and I can more easily break the sound barrier, so I guess the issue is related to the changes in drag. Am I right? (And it's a pity, because that's a nice position to put the docking port). I also installed Interstellar (and removed the rapiers MM patch as it caused them to overheat) but I don't think Interstellar should be the curprit
  16. For ModuleLiftingSurface, especially in the wing parts, i know the stock deflectionLiftCoeff is calculated by the area*0.284. But how is the dragAtMaxAoA and dragAtMinAoA calculated? the drag at max AoA for wings seems to never go over 1, so does this mean it's a multiplier of some sort? Also if you look at stock's big delta wing, and the aeroplane main wing, both have different surface area, but have the same dragAtMaxAoA=0.6 and dragAtMinAoA=0.0, why? If anyone know how these values work, please let me know! Thanks!
  17. What are the aerodynamic properties of this part? Does the big flat part cause drag if you put engines on it? Or does it count as a smooth mk3-to-3x1.25m adapter?
  18. Inline Drag Occlusion in 1.2

    So pretty much every lunar rocket I've been building in 1.2 has some variation of "small 2.5m tank, Terrier, decoupler, larger 2.5m tank." I had a general sense that I might be taking some kind of drag penalty for the change in form factor, but was not exactly sure how it worked or how large the effect was. So, following @Gaarst and @Yakuzi's excellent work on nose cone drag, I whipped up a little experiment. This was my rig: The nosecone, capsule (I edited mass down to 3 tons so I would actually use it in my new career) and top 2.5m fuel tank represent the payload, and will be providing the drag occlusion, if any. The middle piece was my independent variable. I tried four combinations: (1) Terrier alone, as shown here, (2) Terrier with 2.5m interstage fairing, (3) a 2.5m probe core instead of Terrier (selected because it is the same mass as the Terrier, but in the 2.5 form factor), and (4) the 2.5m probe core with 2.5m fairing base. On #4, I could not actually build a fairing, I just wanted to check the fairing base itself didn't cause weirdness. I also drained fuel from the upper tank to balance out the added weight of the fairing when it was used (within a couple kilograms, at least). Just to keep extra variables out, I also disabled the reaction wheel on the probe core when it was used. The bottom 2.5m tank and Reliant provided the thrust. On each test, I set the SAS to hold radial out, and fired the Reliant with only the bottom fuel tank available. I then saw how high each rocket would go after burning through the bottom tank. #1, the plain Terrier, only made it a little over 9,000 meters, #2, the Terrier with fairing, made it over 11,000 meters. #3, the probe core, made it over 13,000 meters! #4, the probe core with fairing base, ended up very close to #3. So the fairing base appears to have no special aerodynamic effects. Results: It looks like parts in front do not fully occlude trailing parts if there is a smaller-size part in between. The lower tank may be getting some drag occlusion, but definitely not as much as if the stack was uniformly 2.5m wide. So all else being equal, it's better to avoid the "hourglass" shape. Using an interstage fairing considerably improved drag, though surprisingly, the net effect was not as good as a pure 2.5m setup. Thus, besides their weight and cost, fairings don't appear to be a perfect option occlusion. It's also worth mentioning that, even when I did NOT reduce payload weight to compensate for the fairing, it still made the Terrier package go higher. This suggests that interstage fairings are probably a good idea, at least as long as the fairing base is staged low enough you're not hauling it to Tylo and back or something. In career mode, though, the fairing might or might not be worth the cost. One final note: this test did not attempt to measure drag occlusion when the rocket is not facing directly prograde. But I would expect the penalty for changing sizes to be even worse in that case, since there's not even perfect occlusion from a geometric standpoint. tl;dr: going back and forth between form factors is bad for drag. If you have to do it, consider an interstage fairing.
  19. Speaking about drag occlusion generated by different parts, are 3.75m parts occluded by Mk3 parts? Thank you. Cheers.
  20. A drag-reducing aerospike is a device (see Nose cone design) used to reduce the forebody pressure aerodynamic drag of blunt bodies at supersonic speeds. The aerospike creates a detached shock ahead of the body. Between the shock and the forebody a zone of recirculating flow occurs which acts like a more streamlined forebody profile, reducing the drag. Does the game take advantage of such things? I don't really understand how KSP aerodynamics work, but it should benefit from these kind of gadgets if it modeled airflow realistically, especially in mods like RSS where the atmosphere part of ascent is quite long.
  21. Hello! Got a problem today on fresh reinstall of KSP 1.1.3 (1289), which I was able to solve myself - but I think I must publish so that someone encountering it will spare himself the time. Symptoms: Parachutes refuse to work. Any parachutes. Attached to any capsule. Anywhere. Be it stock KerbalX, or MK1 dropped from height. The Aerodynamics overlay shows them not working at all. It became so crazy, that I designed a high altitude rocket-plane just to show how crazy the situation is. http://imgur.com/a/kLRh2 Here is a scenario to reproduce the problem, nothing extraordinary: 1) Installed KSP - did not start it yet! (important) 2) Installed Module Manager (2.6.25, current), Kerbal Engineer Redux (1.1.1, current) and Docking Port Alignment Indicator (6.4, current) 3) Started KSP I have tried to remove: - Unity3d settings directory in /home/ - physics.cfg and settings.cfg I have tried to restart the game and sandbox mode. I have played around with vsync on/off and physics settings. To no avail. Solution! 1) Remove the game completely 2) Install it again 3) Run KSP before adding any other mods 4) After at least one run - add the mods. Now the parachutes suddenly WORK. It looks like one of these three mods corrupts parachutes data or does something that leads to that - if KSP never run before.
  22. DRAG_CUBE help

    I'm creating scaled-up versions of the ROUND-8 Toroidal Fuel Tank, and need a hand with drag cubes. The stock part has a custom DRAG_CUBE defined as follows: // AREA DRAG COEFF DEPTH cube = Default, 0.2859113, 0.6272321, 0.6734665, // X+ FACE 0.2859113, 0.6268581, 0.9227022, // X- FACE 1.21, 0.96, 0.2872447, // Y+ FACE 1.21, 0.96, 0.245615, // Y- FACE 0.2958315, 0.6112254, 0.6440083, // Z+ FACE 0.2958315, 0.6160544, 1.104762, // Z- FACE 0, 0.02261333, -2.695719E-09, // BOUNDS CENTER 1.152236, 0.3307782, 1.135139 // BOUNDS EXTENTS // X Y Z In one case, I'm scaling the part by a factor of 2.2 along the X/Z axes, and 4.15 along Y axis. I'll also be moving the Y-coordinate of both attachment nodes up to 0.43 so the tank wraps nicely around the exhaust manifold of a Poodle engine when mounted above it (yes, there will unfortunately be a bit of clipping, but hopefully we don't need to get into that here). MODEL { model = Squad/Parts/FuelTank/fuelTankToroidal/model position = 0, 0, 0 scale = 2.2, 4.15, 2.2 } To visualize it, red is the stock part, and blue is my scaled up version (note some of the values may be approximate): I'm trying to figure out how I should adjust the drag cubes to sensibly represent the increased drag of the bigger part. I read the following links: Drag cubes introduced Explanation and "OMG" Experiments Image showing XYZ face orientation Drag cube scaler/calculator and its announcement But still have some basic questions on how they work: In general, how "tightly" should the values correlate to my part geometry? e.g. Should I be doing calculations based on the dimensions of my part? Or is the system just an imaginary way of visualizing multipliers which should be tweaked using best judgement? (Since drag cubes also affect buoyancy, I'm assuming they need to be fairly tightly coupled to part geometry, and if you start going willy-nillie to tailor the drag you'll end up with unwanted side effects in the water... unless you decouple the drag/buoyancy cubes via buoyancyUseCubeNamed) I infer AREA should roughly correspond to the surface area my part presents to the given face. Should it be calculated from a projection of my part onto that face (or maybe from an outline of the cross-section made at DEPTH)? e.g. The stock toroid projected onto the Y+ face (i.e. viewed from above) looks like this (numbers approximate): So the area is roughly 0.74m2 (or 1.04m2 if you ignore the hole in the middle). That's a bit smaller than the 1.21m2 area in the stock DRAG_CUBE above (I guess for whatever reason Squad used a slightly bigger outer diameter of 1.24m). But what I'm really wondering is why did they ignore the hole in the middle? Does that mean I won't get the benefit of reduced drag from the air rushing through the middle? (It's a valid question - I could build a craft where that hole isn't occluded) How does DEPTH work? Is it to tell the game something akin to where "tip" drag ends and "surface" drag begins? @NathanKell said it should be "depth of widest point from the frontmost point at that angle". I assume that means if you have, for example, a part that looks like a pencil pointing upward, then the DEPTH of the Y+ face should be equal to the length of the pencil's tapered tip, like so: The widest point of the stock toroid tank is at its equator. So I'd expect DEPTH for its Y+/Y- faces to be roughly half the height of the part - but they're both nearly the FULL height. Similarly, X-/Z- are only slightly less than the full outer diameter (while I'd expect them to be much smaller, about equal to the outer radius), and I'm totally confounded as to why they're so different from their X+ and Z+ counterparts. The mesh looks reasonably symmetrical. Does it have something to do with the little gauge dial on one side? If so, why's that bugger have such a big effect, and why doesn't the effect come into play when the wind's coming from the opposite direction? Any advice for determining the drag coefficient? Is it intended to be adjusted to represent the "pointiness" of my part in the given direction (and perhaps the "slipperiness" of the material composing its surface)? Do I have a fair bit of leeway to adjust it (without causing unintended side-effects e.g. to buoyancy)? What are the extents of the drag cubes (last tuple) used for? e.g. Does it come into play when the game compensates for occlusion of stacked parts? Any general guidelines would be helpful. e.g. At one point @NathanKell said that for "a stackmounted hollow part" like a cargo bay, the Y+ and Y- area values should be adjusted to match the non-hollow version of that part. That's a very easy-to-use piece of advice that seems to make sense intuitively :-). Another one was "If the part is not hollow in terms of mesh, but should be (in terms of it being an intake with a flat black section that's supposed to represent a hole), you play with the drag coefficient (second number in the triplet) in the intake's incoming axis." Although I'm wondering, could you not simply "fake" a hole in the drag cube (regardless of whether it's in the mesh) by subtracting the opening's area from the face it points toward (i.e. poke a hole like I want to do with the toroid above, but only for the face the intake faces)? Have the part-level tags dragModelType, maximum_drag, minimum_drag and angularDrag been deprecated?
  23. I hope I'm in the right place to post this, but I've noticed a major increase in the applied drag after the recent update. I did some testing in the current 1.1.2, 1.1.1 and 1.1 versions of the game and noticed that 1.1 had significantly less drag applied than subsequent ones. According to what I could conclude, 1.1.2 applies almost 20% more drag, which is never mentioned in any of the release notes. (1.1.2 just introduced some optimization). This practically grounded 90% of my spaceplanes, so I'm curious if anyone else noticed this? Here are some screenshots with flight data GUI for both 1.1 and 1.1.2. (notice that 1.0.5 aero was more similar to 1.1). Flight stats in 1.1 And the same situation in 1.1.2
  24. Hi, I'm a new poster but have been (trying to) play KSP for a long time now. After a lengthy break, I've picked it up again at v1.1.2 to discover quite a lot has changed. I had a program back in the day for modelling ascents of various ships into orbit and have been trying to update the code to model the new drag cube system. However, when opening my GameData\Squad\Parts folder, none of the .cfg files for any of the parts seem to have the DRAG_CUBE { cube= } parameters as described in numerous discussions on the new aerodynamics system (see link) Am I missing the most recent files, or am I simply looking in the wrong place? Any help is much appreciated, Cheers
  25. I was wondering if it might be an idea to add a wind tunnel to the KSP? Aerodynamics testing is pretty important, but it'd be nice if we didn't have to resort to the debug menu. Tier 1: You only see how much lift something generates. Positive or negative Tier 2: You get the torque overlay. Tier 3: You get the drag overlay. An ideas? Lift is already visible in the SPH and VAB, but I think not the exact amount? Taking a build to the wind tunnel could give you more info on the amount and surface areas, so it wouldn't be completely useless.