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Showing results for tags 'stage'.
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It's not effective, either to have a single gigantic tank for Tylo and back, nor having two hundred separate stages for a trip to Mun. Is there a formula to calculate the minimum fuel to dead weight ratio for each stage in order to have a net delta-v gain for adding that stage?
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The Joint between the Terrier Engine and the TR-18A Decoupler wobbles when I try to do the Gravity Turn to my rocket. Already Did: Strutsss Placing a stabilizer below the Decoupler. Distributing torques to the first stage and second stage. Not having a second stage at all. (But hey, It worked) Its just annoying when I try to do the Turn and the whole rocket wobbles and oscillates, then the mission fails.
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Hello. Please look at my plugin for KSP. It gives you ability to assign your own colors for part' icons on stages. Mode part colorizing: Simple mode: Screenshots: Source: https://github.com/HuXTUS/KSP-StageColorPlugin Compiled plugin (Windows) for download: https://github.com/HuXTUS/KSP-StageColorPlugin/releases License: MIT https://github.com/HuXTUS/KSP-StageColorPlugin/blob/master/LICENSE
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Hey everyone, I recently have been sucked into this game, and I'm loving the math. My question is this simple, determine the altitude a rocket will achieve on full fuel burn of a single stage. I've done a lot of research and have come up with the following example problem to test my algorithm/process of calculation. Let me know what you guys think of below and what I'm missing or potentially a force I haven't considered into the calculation such as lift, as you'll see my answer is off by nearly 3,300m. (For the sake of simplicity the rocket travels straight up in a vertical dimension only.) Known Values of my Rocket: Full Mass [MFull] (Entire Rocket) : 7.5t (7,500kg) Empty Mass [MEmpty] (First Stage Depleted) : 4.5t (4,500kg) Fuel Mass [MFuel] (Both LQ and OX) : 3.0t (3,000kg) Isp [Isp] (Reliant Engine) : 265 sec Thrust [FT] (Thrust Force Atm.) : 205.2kN (205,200N) LQ Rate [BLQ] (Burn Rate of LQ) : 7.105 u/sec OX Rate [BOX] (Burn Rate of OX) : 8.684 u/sec LQ Volume [VLQ] (LQ Fuel 45% Mix) : 270 u OX Volume [VOX] (OX Fuel 55% Mix) : 330 u Known Values of Kerbin: Accel. Kerbin [g] (Accel. of Gravity) : 9.81 m/sec^2 First I will calculate the time required to burn through the fuel mixture. This time will be needed in the final calculation. Tburn =VLQ /BLQ =VOX / BOX << >> 270u / (7.105u/sec) = 38.0 sec Next I convert burn rate units from volume/sec to units of kg/sec. (I assume 1u = 5kg of both LQ and OX) BLQ_M = BLQ * (5kg/u) << >> (7.105u/sec) * (5kg/u) = 35.525 kg/sec BOX_M = BOX * (5kg/u) << >> (8.684u/sec) * (5kg/u) = 43.42 kg/sec BTOTAL= BLQ + BOX << >> 35.525kg/sec + 43.42kg/sec = 78.945 kg/sec (M *Dot = Mass Flow Rate) Determine effective exhaust velocity of rocket motor related to Specific Impulse and Gravity. (NASA Formula) Ve= Isp * g << >> 265sec * 9.81m/sec^2 = 2,599.65 m/s Determine acceleration of rocket (Found this formula on a physics forum, not sure if valid) a = Ve ( BTOTAL / MFULL ) - g << >> 2,599.65 m/s * (78.945kg/sec / 7,500kg) - 9.81m/s^2 = 17.554 m/s^2 Apply classical kinematic physics equation for displacement with acceleration. (Vertical Axis only...) deltaX = 0.5 * a * (Tburn^2) << >> 0.5 * 17.554m/s^2 * (38sec ^ 2) = 12,673.988m So in the end this calculation results in an effective altitude of 12,673.98 meters. If anything, I expect drag (if simulated) among other forces to take away from this value. Instead the opposite occurred, my actual test flight while holding steady to the center of the NavBall resulted in roughly 16,000 meters altitude at 38 seconds into flight (after stage finished burning). Any ideas?
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Maybe I'm missing something obvious here, or maybe it's not possible for some reason, but can anyone tell me how to get Mechjeb to show the amount of delta v per stage independent of other stages in the VAB? What I mean is, let's say I have my main payload stage, which has 1000 delta-v. Mechjeb shows this correctly in the VAB. But when I add a booster stage, let's say it has delta-v of 2000, the delta v of my first stage will be lower (ie, as if it was trying to push the full weight of the craft, including the booster stage), maybe 750. Likewise if I add another booster stage, let's say solid rockets, with a delta-v of 1500, both previous stages will show lower delta v values again. It makes it quite difficult to calculate how much total DV I have, because rather than telling me I have the 3500 total for my booster stages, and 1000 for my main craft, it may show 1500 for stage 1, 1000 for stage 2, and 300 for my main craft... Am I making sense? As I say, maybe I'm missing something obvious, but if anyone could clue me up, I'd appreciate it...
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In 64-bit KSP 1.1, with only one mod (the docking alignment indicator) - launching a fairly large rocket (174 tons in 6 stages): If I save and then attempt to load the vehicle, it shows up on the vehicle list as "116 parts in 13 stages", but there are only six stages on the sidebar. I click "launch". I go to the pad. If I don't do anything for a few seconds, the spacecraft settles in. It appears to be intact, but the first three stages disappear from the stage sequence on the left. If I activate the staging sequence, I get the fourth stage. If I hit the "stage" button before the rocket "settles in", stage one fires as it should, but controls then appear to be locked. I have checked visually - in both of these scenarios, the rocket appears to be intact, just the controls are misbehaving. If I leave the pad after the rocket settles in, then come back, the top half of the rocket falls to the pad immediately upon my return and lights everything on fire. I do not see the bottom half. The spacecraft in question has three probe bodies and no crew. I have tried quitting and reloading, shuffling the stage sequence, and similar with no apparent effect. Has anyone seen similar behavior? Any idea how it might be fixed?
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Does anyone else spend so much time making aircraft, that they never got good at huge rockets, moar boosters and in-orbit assembly? So that when you feel an urge to view the outer reaches of the Kerbol system, the easiest way is to make a plane that leaves bits of itself behind en-route. (Intentionally) https://onedrive.live.com/redir?resid=7003A8806D8A6B2C!727&authkey=!ALzHMCmQJPIc63Q&ithint=file%2ccraft This one's already lost a stage - the landing gear that it took off on, wasn't fast enough to F12 sorry. It'll be raining Rapiers, three of them at any rate. As we pass mach 6, we shed the outboard NERVs. Above 50km, there's no need for the extra control surfaces. Nor those empty wings. It leaves us an aft CG but since there's no real atmosphere we get away with it. In orbit. This stage has about 650 fuel left in it, enough to get us to Laythe I reckon - 5000dV? I couldn't be bothered to fly to Laythe today, but I did verify that the Laythe airbreathing stage works on Kerbin - it's actually kinda sporty. Unfortunately the rest of the plane fell onto and wrecked the space centre. After launching the cruise missile separating the airbreathing stage, the return stage was also given a quick once over. The landing gear of the Laythe stage have already gone by this point. It could probably use some more optimisation but it's a start, at any rate. For career mode games, something a little more prosaic - Or we could just build an utter monstrosity It's easier than you'd think, once you get your head around it. The trick is to stay symmetrical in two axes (lateral, vertical) unless you're a true genius. Tacking on stages to the back of your airplane is fine, just remember to add a wing section to each engine part so that the lift offsets the weight and shedding this item has no effect on your CG. And if your new stage needs more engines, use bicouplers. Don't underslung pods, because you won't be able to keep the nose down when the air gets thin. Those planes I linked, look asymmetric , are asymmetric, but don't act asymmetric because they got wings on them heavy bits. You underslung your motors you get off the boat. Never go full asymmetric.
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Can I have some help with a spacecraft please? I would like it to not explode during launch. The Imgur album below is from me hammering the f1 key during doing the first staging. The tanks spin into the main body and things get a little explody. I don't know what the arrows all represent in the aero overlay, but I assume that the cyan arrows going inwards (from about image 3) from the staged tanks are the problems. Obviously I have tried attaching sepratrons which are not able to overcome the inward force (they do point the right way - just triple checked). I am using the nose-cone that slants outwards hoping that it would push the tanks out. It is also nothing to do with SAS, the rocket is (surprisingly) aerodynamically stable and the SAS is turned off. One thing that I noticed is that the one time I tried staging the other 2 tanks first, they still rolled inwards, but they did not destroy the rest of the ship and I was able to go to space that day. Although that might have been due to many other factors. I am not using any mods that affect the physics. p.s. Please pay no attention to the altitude, speed and angle and what that implies about my gravity turn