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Found 44 results

  1. RizzoTheRat

    When is a parachute safe to open?

    Does anyone know how to work out the safe opening conditions for parachutes? I found this interesting post from @Gaarston calculating terminal velocity with chutes but can't find anything on the safe limits. Presumably the safe limit is based on a maximum force, which will come from drag, so as the Cd and Area will be fixed for a given parachute type it'll be directly proportional to Dynamic pressure, Q. However I can't find any info on it. Using kOS to track Q of a fairly speedy capsule (3 mk1 capsules and a Stayputnik) as it re-entered, I found the Q peaked at about 36kPa when I stopped getting flame effects, it then dropped to about 14kPa, with the radial chutes turning white at around 18kPa, then Q started to rise again with the chutes turning orange at 31kPA and red at 35kPa. I've not entirely got my head around Q having 2 peaks though, I was expecting it to build to a peak and then drop off as it's directly proportional to drag, I guess there's some mach effects there increasing the effective area. The info on the radial chutes in the VAB says they have a tolerance of 4000kPa, which presumably isn't dynamic pressure as that would equate to about 2500m/s at sea level. I'm not even sure that could be a maximum dynamic pressure they can withstand when stowed as they'd presumably overheat and explode well before that. I did find an entry of "Breaking Force = 100" in the radial parachutes cfg file, but no idea what that could be as they're taking way more force than 100N, and I'd need to have a bit of a wade through the topic linked above to try and work out what the Cd and Area are to be able to calculate an actual force at my experimentally derived dynamic pressure to see if it's linked to that, but 100kN sounds too low to me. I might try sticking an accelerometer on a capsule to measure the force when the chute deploys to see if it relates to 100 anything. Anyone got any ideas?
  2. Is there a general rule of thumb as to the optimum altitude/velocity/pressure (Q, I think) to jettison fairings-- where the aerodynamic drag reduction is no longer worth the weight/gravity loss? I don't really need the exact equations-- just a general "feel" for the right timing/altitude. Thinking of firing off a series of sounding rockets to test, but I imagine someone else has done a lot more thinking about it already...
  3. I've noticed a HUGE difference in my Mk2 spaceplanes, but I wanted to make sure it wasn't something I was doing, so I made two identical craft in 1.3.1 and 1.4.1 and launched them with a launch testing script I adapted from the kOS tutorials. The difference is huge and makes pretty much all of my Mk2 based spaceplanes no longer viable. I hope this gets fixed. I loved some of those. Craft file here: https://github.com/quade-ksp/KSP_Craft/blob/master/Testing.craft kOS launch test script here: https://github.com/quade-ksp/KSP_Craft/blob/master/launch_test.ks Video here:
  4. Cheetah_stuck_in_space

    [1.4.1][KOS] Atmospheric Drag script

    Right now im still learning the mechanics of KOS, and while doing this i was trying to use air drag to calculate throttle during ascent. But when i started searching online i coulnd't find any proper scripts to do this, apart from the ones before 1.0. Everyone was saying that you couldnt calculate it now because we don't know the Cd value of ships anymore. But you can actually calculate it on the fly using: Thrust vector + Gravity Vector + Drag vector = total force on ship(Vector). After puzzling for a while with vectors i managed to come up with this script which returns the drag as the vector AirResVec: Important notes!!: Doesn't work while landed because the script will think the drag is keeping the craft from falling instead of the ground its standing on(edit: now fixed by adding a failsafe that will return 0 drag if the ship is either landed, not launched yet or splashed down) There is a slight delay when changing the throttle which will cause the air drag vector to freak out for a split second You need an accelerometer on the craft to calculate the (wait for it...) acceleration.(edit: these two issues are now fixed by using the KO's built-in ship:velocity instead of ksp's accelerometer which averages the acceleration from the last 0.4 seconds which caused glitches) I hope this helps the community since the script wasnt available when i needed it. BTW. here is a pictures of the vectors in action:
  5. As the title states, I am using a mechanics bay to shield some science instruments. I've also used a regular cargo bay from 1.25 and the mk2 line for planes. The items contained within them, when aero debugging is turned on, are not listed as shielded, and as expected for random objects hitting the atmosphere at mach x, the drag is insane. Anyone else experienced this? Its killing my plane game.
  6. I'm making some really big truss segments, but the procedural drag cube treats each part like it's clad in plastic. When falling through the atmosphere, it basically drifts down like a feather. I could just make the parts super heavy, but they're supposed to be made of lightweight materials. Anyone had a similar problem in the past? I could use the help
  7. KSP Version: 1.3.1.1891 (Windows 7 x64), fresh install, fresh sandbox savegame. I keep this particular KSP install for such testing only. Mods / Add-Ons: All Stock Description: if there is a long enough part inside a cargohold that consists of two shorter ones, then drag is applied to the payload. (I think its because the game thinks that payload part is clipping through the cargobay. Although visually it is only clipping through its front or its back as it is longer than the cargobay.) I also think the problem is known. But I'm not sure. Also I'd like to know if it's gonna be fixed or not. The reason I'm reporting this is because there are many modded parts that are longer than the longest cargobay available. Fuel tanks for example. It also limits how one should attach their payload inside cargobays. UPD: not every part bugs. Incomplete list of parts which I've tested (yes = causes the bug): - FL-T800 Fuel Tank: yes - Modular Girder Segment XL: no - M-Beam 200 I-Beam: no - Mk1 Cockpit: yes - Orange Tank: yes - RT-10 Hammer Solid Fuel Booster: yes (omg i've ignited it inside my cargobay.. omg.. oh nevermind it didnt explode) As a lil' bonus I've also tested the situation when a small part is placed between two cargobays. It didn't bug at all (tested with 2x FL-T200 Fuel Tank). Steps to Replicate: 1) Create a plane with two connected short cargobays so they make a longer one together. 2) Put a long enough part inside - its length must be longer than one of the short cargobays. Example: two connected Mk3 Cargo Bays CRG-50 and an Orange Tank inside. 3) Attach additional parts like a Cockpit, landing gears and an engine (if the payload isnt a fuel tank - then attach a fuel tank too of course). 4) Launch the craft. 5) Make aero forces visible in parts' gui menu through the debug menu. 6) Open the payload right-click menu. 7) Accelerate and watch its drag. Result: The payload's drag isn't zero although it must be as it is fully enclosed. Fixes/Workarounds: - attach the payload differently (if there are multiple crafts or parts as a payload); - use different nodes; - use the largest cargobay available; - don't put larger parts inside Other Notes/Pictures/Log Files: Both Mk3 and Mk2 cargobays have this problem. I believe its an internal technical logic problem, not a bug. Its just how the game calculates drag. But still it is a problem. Craft files: Mk2: https://www.dropbox.com/s/kk4h6y8h4alamx0/Bugged Mk2.craft?dl=0 Mk3: https://www.dropbox.com/s/fe4zaluf436nniq/Bugged Mk3.craft?dl=0 Screenshots (the right part-menu reflects the payload on both screenshots): Thank you Squad for making one of the best games! No sarcasm involved. Bugs happen. (I believe there is no need to include logfiles. Will attach if Im wrong.)
  8. In a plane the Centre of mass is just ahead of the centre of pressure, so it is stable. When elevator movement is given, it does go nose up but it doesnot climb. Instead in it tries to come down. How to make it climb. P.s Rhodes34 airfoil if used inclined at 8deg Basically I want to know what affects the rate of climb and vertical velocity
  9. Just wondering. Can you land using drag alone? Parachutes don't count here.
  10. 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?
  11. 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!
  12. 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?
  13. 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?
  14. 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
  15. 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!
  16. Basilo1146

    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.
  17. 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?
  18. 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?
  19. It'll be really helpful to know the Lift&Drag characteristics on altitude and speed, to fly a proplane. Anyone knows something about this?
  20. 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.
  21. 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
  22. 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)
  23. 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
  24. 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!
  25. 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?