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  1. This is an in-depth tutorial, but still directed to beginner-intermediate players, on how to do a proper launch and gravity turn with the new aerodynamic model introduced as of version 1.0. This tutorial works for versions 1.0 to 1.3. More than giving a script or set of instructions, my goal with this tutorial is for you to gain an understanding of the factors that affect your rocket's behavior during launch, so that you can apply it to any rocket you fly. For that, you'll need to go through the entire post, but I'm also including a TLDR as a "cheat sheet": TL;DR (courtesy of @kBob) 1. Turn ON SAS and set throttle to give TWR of ~1.5. 2. Launch! 3. When your speed reaches 50 m/s, perform a pitch over maneuver (tip towards the East until pointing between 5° to 10°). 4. When SAS stabilizes (i.e. the control input arrows on the bottom left are all centered), turn it OFF. Avoid control inputs and use only throttle to control your gravity turn (throttle up to turn slower, throttle down to turn faster). 5. When your altitude reaches ~40 km, turn SAS ON. Start pitching down manually towards the horizon and adjust throttle to keep your Ap around 45 seconds in front of you. 6. When your Ap reaches the desired altitude, cut your engines, coast to Ap and circularize. ========================================================================================== General Notes on Gravity Turn You all probably know by this point that to get into orbit you need to go up, above the atmosphere, but you also need to go sideways (i.e. horizontally) very fast. To do this, we could launch straight up until we're out of the atmosphere, then point sideways and accelerate to orbital speed. But that would be very inefficient. We want to launch in a way that we gradually turn sideways while we ascend. This is called a gravity turn. The best way is to do a real gravity turn; that is, a turn caused by gravity and aerodynamic forces, rather than one achieved by actively turning the rocket. It is important to keep this in mind. Design Items Before even launching, you need to take these design items into consideration when building your rocket: TWR: Your thrust-to-weight ratio (TWR) at launch should be relatively low, around 1.5. A higher TWR at the beginning of the launch makes it harder for your rocket to turn naturally, as gravity will have less influence on its trajectory, making it fly straight and screwing up your gravity turn. Keep in mind that drag losses are almost negligible in the new aero, unless your rocket is shaped like a brick or you are going extremely fast in the lower atmosphere. Thus, a slightly higher TWR of around ~2.0 in theory is more efficient, but only if the launch profile is flown correctly. The drawback is it makes your rocket less forgiving in terms of control during ascent, and it shortnes your widnow to make a pitch-over maneuver. What usually ends up happening is that you have to force the gravity turn manually, which does generate significant drag (because you expose the sides of your rocket to the airstream anytime you deviate from your prograde vector), and causes steering losses (Dv wasted on changing direction rather than gaining velocity). This reduces overall efficiency and defeats the purpose of having a higher TWR to begin with. A higher TWR also causes increased stress to the craft, inducing wobble and risking a RUD, especially when trying to maneuver. You may experience heating issues too. For these reasons, in my experience, a TWR of ~1.5 is a good sweet spot between efficiency and controllability of the rocket. Smaller and lighter rockets handle higher TWR's better than big and heavy ones and each craft will have its own sweet spot; you are encouraged to experiment. If you find your TWR at launch is too high, either use a smaller engine or just throttle down, and vice versa. As a final note, all rockets will have their TWR go up as the launch progresses due to shedding weight by burning fuel. This is normal and you should manage by reducing throttle throughout the ascent as needed (more on this below). You can check your TWR with the Kerbal Engineering Redux mod (KER) or with MechJeb, or if you're running a stock game, the G Force meter roughly doubles as a TWR meter (if the G Force meter is pointing at 1 your TWR is roughly 1, and so on). Aerodynamic Stability: You want your rocket to be aerodynamically stable. That means that it will have a natural tendency to fly straight, instead of, say, sideways. Any object that flies through the atmosphere will naturally orient itself with its center of mass (COM) facing forwards relative to its trajectory and its center of drag (COD) facing backwards. You can see this in darts, arrows, badminton cocks, etc. Similarly, you will want to have your rocket's COM in front of your COD. To ensure this, add 3 or 4 winglets or wing surfaces with radial symmetry at the base of the rocket, and if possible cover your payload in a fairing to make it more streamlined. If your rocket insists on flipping, you need to add more/larger wings at the bottom. If that still doesn't fix it, it means your COM is shifting back too much as fuel is burnt. The heaviest part of a rocket in KSP is usually the main ascent engine(s), so the COM will tend to move back as fuel is spent. The easiest way to fix this is to add a small fuel tank at the top of the stage that's experiencing the problem and lock the tank in the VAB (right click on the tank and select the green arrows for both fuel and oxidizer). This fuel tank will act as ballast keeping your COM forward. You can unlock it manually in flight when the rest of the stage's fuel is gone so as to not waste it, and then stage as normal. Ascent Profile Once you've implemented the above design items, follow these steps for your ascent: 1. Turn on SAS and set your throttle to whatever will give you a TWR of ~1.5. 2. Launch! 2. As soon as your speed hits 50 m/s, perform a pitch-over maneuver to begin your gravity turn. To do this, tip your rocket towards the East slightly, until it is pointing between 5° to 10°. Don't start pitching over before your speed is ~50 m/s, otherwise you will likely find yourself horizontal within a few seconds, as your winglets won't be biting into the air hard enough to provide stability. The higher your thrust, the more you need to pitch over initially, because higher thrust makes the rocket want to go straight. If you're using a TWR higher than 1.5, your pitch-over should be to at least 10°. 3. As soon as your SAS stabilizes (i.e. the control input arrows on the bottom left are all centered) turn off the SAS. Watch closely for this moment, as you will have only a small window of a few seconds at most before the SAS starts trying to resist the gravity turn. Turning SAS off while it's trying to steer will cause your rocket to become unstable and lose its heading or possibly break up. You should be done with your pitch-over maneuver and have your SAS turned off by the time your velocity is around 100m/s. If you take too long and your rocket is going too fast by the time you're done, it won't want to continue turning (fast rockets like to go straight, remember?) and you'll have to force the turn manually, which is inefficient and causes stress on your craft. As mentioned above, a gravity turn should happen on its own and not as a result of control input. For particularly unwieldy rockets, you can lock SAS to prograde instead of turning it off during this phase. However, stock SAS is far from perfect and it's best to let gravity and aerodynamic forces do the steering for you. If you do use SAS, be sure to disable it before you hit 35 km to avoid you craft from jolting down suddenly when the navball automatically switches to orbit mode, which happens at around 35 km. 4. Enjoy the view while your prograde marker gradually sinks towards the horizon; your rocket will follow on its own thanks to gravity and aerodynamic forces. Try to avoid control inputs during this phase (i.e. no AWSD), just let it fly. If you need to make adjustments, use throttle. Remember, lower thrust means the rocket turns more, higher thrust makes it want to go straight. At about 10 km altitude, you should be pointing roughly to 45° and your speed should be around 500 m/s. If at 10 km altitude you're still pointing above 45°, your TWR was too high and you went too fast and/or your pitch-over maneuver was too gentle. Next time throttle down more or make a more aggressive pitch-over maneuver. On the other hand, if you're pointing below 45° at 10 km, you went too slow and/or your pitch-over maneuver was too aggressive. Next time use higher thrust or do a gentler pitch-over maneuver. If your rocket flips on its end at any point, it's not aerodynamically stable enough. See above under "Aerodynamic Stability" for possible solutions. 5. At around 40 km altitude, turn SAS back on and start steering manually; use pitch and throttle to keep your Ap around 45 seconds in front of you. Any time you're burning above the horizon, you're wasting part of your thrust to gravity instead of gaining horizontal speed; this is called gravity losses or gravity drag. In the initial stages of the launch, you can't help incurring gravity loses because you need to gain vertical speed to get out of the atmosphere. The atmosphere also means you can't steer away from the prograde vector without inducing aerodynamic drag, steering losses and/or destabilizing your rocket. However, by the time you get to ~ 40 km, you'll have enough vertical speed and the atmosphere will become negligible. Thus, at this point you want to begin gradually pitching down towards the horizon. During this phase, you will also start adjusting your time to Ap. It's most efficient to perform your orbital insertion burn right at Ap, so you want to keep it "hovering" only a few seconds in front of you. Of course, you don't want to it to get too close either, otherwise you risk passing it and falling back down into the atmosphere. A time to Ap of ~45 seconds is a good rule of thumb to balance safety and efficiency. To control your time to Ap, use pitch and throttle. If your time to Ap is more than 45 sec, throttle down a bit and point more horizontal, and vice versa. Avoid pitching below the horizon. Continue adjusting pitch and throttle until your Ap reaches your desired altitude, at which point you can cut your engines, coast to Ap and circularize. Note that as you approach orbital speed, there will be a point when your Ap will begin shooting away even if pointing straight at the horizon and no matter how much you throttle down (unless you cut the engines of course). If you reach this point, just let it go until engine cutoff; any efficiency gains from keeping your Ap near you will be negligible by then. Advanced Mode Try doing the ascent and orbital insertion in a continuous burn. This is the most efficient profile (citation needed) and it's extremely satisfying. Easier said than done, though. To pull it off, you need to allow your time to Ap to creep closer and closer during steps 4 and 5, while not allowing it to get higher than your intended orbital altitude. You do this by reducing throttle and lowering your pitch in a more aggressive manner. The closer you are to orbital velocity, the closer you can allow yourself to get to your Ap. You want to hit orbital velocity exactly at Ap. There will be much trial and error and the exact procedure will vary from rocket to rocket, but give it a try!
  2. I'm attempting to build a massive SSTO rocket but when I attempt to start turning in the air my rocket instantly explodes. I'm using part clipping to get the diameter of the rocket smaller but from what I understood that shouldnt affect the physics of the craft. The flight log says that there was a structural linkage failure between two adapters high up on the rocket in a random spot. If it helps I'm using vector engines attached to an engine plate onto a 5m fuel tank.
  3. I ask those with experience in real solar system how the gravity turn goes. in the stock game, you generally want to turn very fast, starting already around 50 m/s, being down at a 45° angle already at 500 m/s. that because in stock you orbit at 2200 m/s, you want to be horizontal at that speed. in real solar system, at 2200 m/s you still miss over 5 km/s to orbit. I had experiences where I did start angling down early, and I had to pull up later. on the other hand, I am now trying to go straight up until around 15 km altitude, and while this enables a proper gravity turn afterwards, going straight up at 700 m/s doesn't feel right. it can't be optimized, can it? and orbital launches in rss last way too long for me to want to go by trial and error. any good tip on when I should start turning?
  4. I asking about accent profile as a hole actually the content of the post was incomplete I should have been more specific When to start gravity turn and what is optimal speed at a given range of altitude
  5. I'd prefer at least 200 or 300 m/s for docking then. As for low TWR, what it means is that: 1. if I try to launch vertically with a standard gravity turn, it takes a lot of time to build up vertical speed - during all that time gravity is pulling down and costing delta-v. 2. If I use my plane ascent profile, I lose slightly more delta-V to drag. However, I cans till get going quickly as the wings help provide lift to keep the SSTO in the air, while the engines provide half vertical and half horizontal thrust. 3. TWR is really only an issue during the earliest parts of the ascent, as when the craft burns off its fuel it becomes much lighter. As for wing placement, the center of lift is where it should be on a good plane. It's slightly below the center of mass so the wings can sort of shield the fuselage, but the plane flies well. The plane is balanced so that the center of mass does not shift when fuel drains, like a jet SSTO, and there is enough wing area to not be too much of a brick. A fighter jet it is not, however.
  6. Testing results: MOAR POWER worked great - I doubled the thrust on each design and now they reach orbit with plenty to spare using a standard gravity turn via MechJeb. Thank you all for your help!
  7. I'm going to assume that when you say "SSTO", you actually mean "spaceplane" instead. Because it's trivially easy to make a standard rocket go single stage to orbit with plenty of dV left over. Your plane has 4000m/s of vacuum dV, which should be plenty, given that it should only take about 3400m/s to reach low Kerbin orbit with a standard gravity turn trajectory. Hence, your choice of trajectory is to blame for losing about 600 m/s worth of dV along the way. Getting more TWR and climbing a little longer can certainly help improve this. But keep in mind that one major contributor is your launching off of the runway. That's just never going to be as fuel efficient as a start from the vertical pad. Also, if getting more TWR means that you lose maximum dV in return, you may find that you gain little to nothing along the way. Your maximum possible upside from trajectory optimization is less than 600 m/s; if you stick to the runway start, it's probably in the realm of 400 at most. Switching from a Dart to a Swivel will drop your dV by about 300 m/s, depending on how much the extra weight is going to impact your plane. So you might gain about 100 m/s tops when reaching orbit. Workable, but not ideal. (Of course, all of this is guesstimated, so your results may vary ) Another thing you can do is take a page out of the Space Shuttle's book, and make do with flying like a brick. As in: bring less wing, or bring more tank. This makes your landing approach harder, but it'll give you more dV to work with in orbit. You're at less than a 12x multiplier of your Isp in terms of dV, so you aren't that deep in the diminishing returns of your mass fraction just yet. If you can get back to like 4000m/s while mounting a Swivel, without increasing your wing surface, that should allow for more fuel leftover in orbit.
  8. Since the original got lost, I thought I'd revive the old FAQ thread. I think I found the most up-to-date version, but please let me know if anything is missing. All credit goes to the original authour for the time and effort spent in creating and maintaining the original list, so a big thanks to him for that. As with the original thread, please don't ask questions here, but feel free to suggest frequently-asked questions that can be added if needed. Frequent Asked Questions KSP in general. Q: Why is my game constantly crashing? Especially on scene changes. A: Most likely you're simply running out of memory. The 32 bits KSP version can't use more than 4GB. (The windows version dies at about 3.3-3.4GB on average, the OSX version at only about 3GB.) Loose some mods or switch to the 64bits version. On PC it's also possible to use -force-opengl. (Success not guaranteed but many people have had great results with it.) Q: I have 8GB RAM on Win7 64 bit. Why does my game keep running out of memory. A: As with the answer above. 32bit KSP can't use that extra memory. And even a 64bits game can run out of memory when too many mods are installed. Q: My computer has X cores, yet KSP runs at a low framerate. / KSP uses only a fraction of my CPU. What's going on? A: KSP runs on the unity game engine. As a result KSP physics are still single threaded. The physics calculations will jump from core to core but you can only only use one out of the X cores at any one time.. More cores will end up meaning you are using a smaller fraction of your processing power. Also, bear in mind that depending on what's slowing you down, the bottleneck might not be your CPU at all-- for example, your graphics card may be having trouble keeping up with visual f/x. Q: Can I de-orbit a moon? A: Short answer: No. Long answer: No. All planetary bodies are 'on rails'. Their orbits are fixed and can not be changed by in-game physics. Q: But what if they were not 'on rails'? Then you can de-orbit a moon, right? A: Still no. In theory it would be possible but the volume of fuel tanks required would be roughly the same size as the body you're trying to de-orbit. The game engine will not permit craft of that size. Even if the game engine would allow such craft it would take many decades to burn through that amount of fuel even at 4x physics warp. (YouTuber Scott manley 'tries' to de-orbit Gilly.) Q: I'd love to use mods, but that's not the way Squad intended it to be played, right? A: Did you notice the weekly showcase of mods by Squad on Modding Monday, and the six subforums devoted entirely to mods? The mods are there to enhance the game as you see fit! Q: How do I install mods? A: See "Running KSP with mods / add-ons" section, below. Q: Is MechJeb (or any other mod) cheating? A: The object of the game is to enjoy it. If you enjoy the game more using MechJeb (or any other mod), do so. If you enjoy the game more by not using it, don't use it. Don't let anyone tell you what the 'true' way of playing KSP is! Q: Is [modname] compatible with KSP version x.x.x A1: Search the forum for the relevant [modname] thread. Don't just browse through but actually READ the title, the first post and the last 2 pages. If you're still not sure check the dates of the last few posts and the date the OP was last edited. When the posts are all older than a few months or when a lot of posts just ask for updates you're probably out of luck. A well maintained and up-to-date mod gets at least a few posts per week. Also check the mod creators forum activity. Hover your mouse over his/her avatar and check the 'last visited' date. If the mod creator has not visited the forum in a long time the mod too is most likely abandoned. A2: When in doubt the easiest (and often fastest) method of getting an answer is to just go for it. Just download and install [modname] and see what happens. As usual you should make a back-up of your current game or create a separate install to keep your current game safe. A3: If all else fails, ask in the relevant [modname] forum thread. That's the place the [modname] users hang out. That's where they know the answer. Q: What is the official name of the Kerbal currency? A: It's called Funds () as in "The rocket costs 100,000 funds". Q: I don't understand why the game doesn't include [feature x]. It would be so much better with it! A: There is an entire sub forum dedicated to suggestions. However, make sure your request is not included in the 'Already suggested list', or on the 'What not to suggest' list. Keep in mind that being on the 'what not to suggest' list doesn't mean it won't be implemented; female Kerbals were on that list, for instance. It just means that Squad is aware of these requests but can not guarantee such a request would be implemented or even entertained. Also, while stock might not offer your feature, it's very likely that there's a mod for it! Q: When will the next update be released? A: Soon™ SQUAD never gives release dates to avoid disgruntled users when deadlines aren't met. Q: "The barn" What is it? Where is it? Why isn't it? A: The barn as it was shown in the previews was generally not received in a positive way by the community for various reasons, and thus left out in Career mode. Most complaints where about bad quality rendering (especially the textures), out of style with the other buildings and haphazard use of objects that didn't make sense (roads leading nowhere, etc). One of the most recent discussions about it can be found here. Launch, lift-off and orbit. Q: Why does my rocket flip when I turn 45 degrees at 10km? The tutorial says that's what I should do. Ashort: The tutorial you're looking at is outdated. Since v1.0 aerodynamics have drastically changed, drag has become a serious factor that can no longer be ignored. To avoid flipping start your gravity turn very shortly after lift-off and be gentle. If you get Mach effects in low atmo you're going too fast. Along: Drag pushes the rocket backward, while inertia keeps it going forward (along with thrust). The different parts of the rocket provide different amounts of drag and inertia: heavy parts provide more inertia while wings, airbrakes, and parachutes provide more drag. Since engines are heavy, their inertia will cause that part of the rocket to continue forward, while the drag on the rest of the rocket will pull it backward. Once the rocket tilts, this causes it to be forced into an orientation where the heavier end points forward - in this case, upside down. This is a real problem rockets have to deal with. The simplest solution is to add parts that provide a lot of drag (wings or airbrakes) at the back end near the engines. If this is not enough, even with careful flying, use the right-click menu to disable fuel in the tanks near the front until the tanks near the back are nearly empty, so as to keep the weight of the fuel near the front of the rocket and due to the above physical effects keep it pointed the right way. Q: My contract won't complete. A1: Are you sure you're orbiting in the right direction? Watch how the highlights on the target orbit are moving. You should be going in the same direction. Also check the AN and DN markers, if they are close to 180 you are orbiting in the opposite direction. A2: The contract system still contains a few bugs. If you are confident you've met all the contract requirements don't despair, Quicksafe [F5] and exit the game. Restart the game and return to the craft that failed to complete. Almost guaranteed now the contract will complete without a problem. Q: Why is it so hard to make a shuttle? A: Because shuttles are really, really hard. One of the hardest things to build in KSP. There are all sorts of off-centre thrust issues to cope with, which change quite radically as the SRB's then main tank separate. There are also lots of drag/lift problems with wings on a rocket. Almost any other way to get to orbit can be designed, built and flown more easily and efficiently in KSP. While you can easily find the parts to make a craft that looks like NASA Spaceshutle, that craft will not behave in the same way given the differences in mass, drag and thrust distribution. Q: Can you make a rocket as efficient as an SSTO spaceplane? A: Yes; build a rocket that uses a Single Stage to get To Orbit. It is exactly as efficient as an SSTO. It IS an SSTO. Spaceplanes aren't efficient because they are spaceplanes, they are efficient because they use air-breathing engines. The second factor that makes SSTO Spaceplanes economically efficient is that they are relatively easy to land back at KSC. The closer to KSC you recover your craft they higher the refund value. Landing back on the runway or launchpad will result in a 100% recovery value. But of course SSTO rockets can also be de-orbited and landed at or near KSC for full recovery. Q: SAS won't activate. Even though I have a Kerbal in the cockpit KSP says I do not have a pilot. A: Your 'pilot' might not be a pilot. Kerbals come in 4 types; pilots, engineers, scientists and tourists. All types have their own use and abilities (except tourists, they're just high-value seat fillers) and only pilots can use SAS. Higher level Kerbals have higher skills. To use more advanced SAS features either use a better trained pilot Kerbal or higher level probe core. Q: [.] (period) toggles the visibility of the NavBall. How do I permanently keep the NavBall visible in the map screen? A: Go to the main menu and open settings. Under the "General" tab uncheck the option to "Autohide Navball in Map View". Q: What is Delta-V / dV / ΔV? A1: dV literally means 'change in velocity'. Basically what you can do depending on the amount of fuel you have, the total weight of your craft and the efficiency of your engines. A2: Mathematically, delta-V is calculated with the Rocket Equation - it takes the form: delta-V = ln(M/Mo)* Isp *go Where delta-V is the change in velocity (a vector that's a dot-product of the scalar component of speed with the vector component of direction), ln is the natural logarithm function (look for it on a scientific calculator, or use =LN() in MS Excel), M is the full mass of the rocket stage, Mo is the dry mass of the rocket stage (i.e. what it weighs when all its fuel tanks are empty), go is standard gravity (9.81 m/s2regardless of what body you're orbiting/launching from) and Isp is the specific impulse of the engine (a way of measuring the engine's efficiency). It's importance, as has been mentioned, is in determining the total magnitude of the changes the rocket may make to its velocity before it runs out of fuel; in the process it determines where a rocket may go given a certain mission profile. There are three main ways of increasing a rocket's delta-V: 1) improving propellant mass fraction (i.e. moar fuel) 2) increasing specific impulse (by selecting an engine combination that increases this value - the main reason nuclear engines are recommended for interplanetary flight) 3) staging (shedding mass that's no longer needed, which has the effect of improving the propellant mass fraction) Atmospheric flight, rovers and surface activity. Q: My rover rolls over on low gravity planets/moons. A1: Widen your wheelbase and lower your centre of gravity. A2: Remap your controls to IJKL or use docking mode in order to steer independently from the reaction wheels. A3: Right-click all reaction wheels and toggle them off. (Most pods and command modules also contain reaction wheels.) A4: Toggle soft controls with [Caps Lock]. The orange pitch/roll/yaw markers in the lower left hand corner turn blue. Q: Why won't my parachutes deploy trying to land on Mun? A: No atmosphere = no parachutes. Parachutes only work on Kerbin, Eve, Duna and Laythe. (And Jool, but it is unlikely your ship will survive long enough to use them.) Q: My jet engines won't work on Duna/Eve. A: Jet engines need oxygen. Only Kerbin and Laythe have and oxygen atmosphere. Q: Why is my plane uncontrollable in flight? A: Planes that actually look like an real life aeroplane usually fly best. Although it is slightly outdated this tutorial will show you the basics. A more up-to-date tutorial can be found here. Q: Even at over 100m/s my plane won't take off before the end of the runway. A1: Your rear landing gear serves as a fulcrum. It's placed too far behind the CoM (Check one of the two tutorials). Another method is to design your plane to sit in the runaway with a slight pitch up angle instead of parallel to the surface. A2: With a Centre of Lift (CoL) too far behind the CoM your control surfaces might not be strong enough to push down the tail and lift the nose. Either move the CoL further forward by relocating the wings, adding canards or increasing the effectiveness of the control surfaces by increasing their size, deflection angle or distance from the CoM. (Or any combination.) Q: My plane violently veers off the runway. Why? A1: Your landing gear is misaligned. Make sure you don't have any toe-in or toe-out. Even a tiny, invisible misalignment can cause this problem. It can happen due to the curved shape of the part you're attaching the landing gear to. One way to fix this in the SPH is to select the rotator widget ("3" key), turn on absolute snap ("F" key), then wiggle the landing gear one notch out and back to parallel. This guarantees perfect alignment. A2: You are wheelbarrowing. Too much lift too far behind the centre of mass (CoM). The tail of your plane is lifted off the ground before the nose and it starts to fall over making it steer either left or right. A3: Your connections are too weak. Connections between parts are always a bit flexible. Use (auto)struts to shore them up. Q: Do I have to bring those science experiments back? I left them on the Mun and didn't get credit for reading them. A: No, all you need to bring back is the experiment data. If you have Astronaut Complex 2, you can get out of your ship. Once outside, get near the experiment, right-click it and remove the experiment data. Then get back in the ship and the experiment will be stored. You can also run the experiment again. Doing this over and over can get you a lot more science on a mission than you were getting before. With the release of KSP v1.2 a new part was introduced; the Experiment Storage Unit. In addition of storing science like any other crewed pod it can also be used to 'pull' all science data into storage. NB. The Goo canister and Materials bay are single use experiments. After data removal (through EVA or transmission) the experiment will be inoperable. To use it again you will need a Scientist or Lab to clean/restore it. Running KSP with mods / add-ons Q: How do I install a mod? A1: Download your mods from Curse, Spacedock, Kerbaltek or any other source you desire. Most mods come in .zip format. Mods will have to be installed in the GameData folder. Search for the GameData/ folder and open it. At the dame time open the .zip you downloaded. Some mods already contain a GameData/ folder. If yours does, open it. Drag and drop the contents into the GameData/ folder. Here's a useful discussion about the details. A2: As an alternative to this manual installation, there's a utility called CKAN that some folks like to use, which is an automated "mod manager" that takes care of downloading, installing, and updating mods for you. (Not all mods are available on CKAN-- it's up to the mod author-- but many are.) Q: I'm looking for a mod that <does thing>, how do I find out whether there is one and what it's called? A: Best way is generally to post a question in the Add-on Discussions forum. Q: I have a question about a particular mod. What's the best way to get help? A1: Usually the best place is to find the mod's release thread in Add-on Releases, and then ask there. That's where the expert users (and author!) of the mod generally hang out, so it's usually the best place to get answers. If your question happens to be a "tech support" kind of thing (e.g. "it's not working!" or "I keep getting a bug!", etc.), then you might want to review the How to Get Support thread, beforehand, for an idea of what kind of information people are likely to need from you. A2: Alternatively, you could just post your question in Add-on Discussions or Technical Support (modded installs) as a new thread. Usually you get more "bang for the buck" by posting in the mod's thread, though.
  9. I designed a basic rocket and it performed quite well. It even got into the gravity turn without need of steering input. Then I decided to try to explore the limits o the design a bit and among other thing I wanted to look how it behaved without the basic fins. To my surprise, it don't flip but also don't get into the gravity turn by itself. Despite being launched with more tilt than the original craft it went up. And is not that it didn't turn at all, rather it osculated slightly west-east, as if there was some sort of self-righting mechanism. Just I have no idea of what it might be. There is the craft file if anyone is interested in trying it for himself: Strange and a picture
  10. hi, after several launches Gravity Turn gave me this values: This is the probes launcher: These are two videos that show the same thing: as soon as the first stage detaches, the launcher no longer can maintain the alignment with the prograde direction and for some seconds it pull up its nose in a non-aerodynamic fly. I just would like to understand why of this behavior? have any ideas? I don't know... too long fairing? Full launch: https://www.dropbox.com/s/69kj8n4zjilhxyy/launch.mkv?dl=0 Short launch: https://www.dropbox.com/s/ey9wt7hvsla5qcz/short launch.mkv?dl=0 Screenshot: (look navball aligment)
  11. When you ask for help with a rocket design, it really does help to include pictures of said rocket- or even better, a video, or better yet the craft file- or else all we can do is guess at the problem. There's a big difference between a vertically and horizontally launched SSTO, between an SSTO rocket and an SSTO spaceplane and things like engine and payload placement can create vessels that handle in dramatically different ways. What speed do you reach before you start your gravity turn, what altitude are you at and how far do you pitch over? Starting your turn earlier (50-100m/s) and pitching only slightly (5-10 degrees) minimises the forces applied to the craft from aerodynamic drag and is less likely to cause the rocket to start flipping and tear itself apart, whereas waiting until you've built up a lot of speed and then aggressively turning causes a lot more stress on the craft and is more likely to cause things to break apart. Try to stay close to the prograde marker on the navball to minimise drag, throttle your engines back once your time to apoapsis reaches about 40-50 seconds and keep burning until you reach the desired apoapsis, then do a circularisation burn- if you do a gravity turn right, the final burn to enter orbit should be pretty small. SSTO rockets are hard. You need to build something with the thrust to lift off the ground, the delta-V to make it all the way to orbit and still carry a useful payload, then preferably return it to the surface in one piece. Atmosphere-optimised booster engines are inefficient in space, while vacuum-optimised engines don't work well (or at all) in the thick air near sea level; aerodynamic features are critical at low altitude, but dead weight in space; carrying extra weight reduces delta-V, requiring more fuel, meaning more weight, meaning more thrust is needed, meaning more engines, meaning yet more weight, and so on. It takes a lot of effort to make a functional SSTO rocket, never mind a good one, and there's a lot of trial and error involved. Don't give up
  12. I have seen some guides say throttle down if it the turn goes too fast, but in someone else says no, do 5 degree force turn for adjustment. But which is actually better?
  13. nope, no RO or other tweaks. after reading all the stuff RO does, i decided some of that was too annoying to keep track of. as for other tweaks, I decided to go rss to increase difficulty, balance tweaks would defeat the purpose. The rocket is the one here As it is, it keeps crashing the pc because it's too big and complex. I know that with one less stack of boosters the pc can handle it, but i missed orbit by some 200 m/s. I'm trying to see if I can optimize the ascent profile to recover those 200 m/s. It's a big asparagus stack, it starts with twr 1.8 and it gradually goes down as more boosters are discarded. Last stage is twr around 1, with 2000 m/s. Everything before that is no less than 1.4 I don't want to use mechjeb or anything. plus, seeing as how mods increase lag and my pc is already crashing, i don't want to add mods just on principle. Normally, I would have gone for a more horizontal profile. Especially with a rocket so big, aerodinamic losses are less than gravity losses - despite the draggy payload. However, a flatter ascent profile means that I will level up early. This can easily be countered by pointing upward of prograde just enough. But that beast is already very draggy - even on a purely vertical ascent, maxQ is around 30% of weight; pointing above prograde while in the lower atmosphere would increase drag immensely. Which is why I was reluctant to do it. Also, I've seen real rockets and they go straight up for several km before starting the gravity turn, so I figured it could be the best way. I will have to try that, though. If nothing else, because I already spent 2 whole afternoons trying to launch that monster and getting the pc crash every single time. Once I even reached the second-to-last stage, wasn't even lagging so hard anymore, and then it still crashed.
  14. That's probably going to be fine. It looks like you have a terrier like my example above. If you switch the dV reading to vacuum, you'll see the dV of your upper stage with the capsule shoot up. You also might want to fire your core engine at launch and just leave the throttle down so you have some real pitch and yaw authority. Would make doing your gravity turn easier.
  15. @Ariggeldiggel I downloaded the craft file, and I was able to use it. I ran a few tests on the craft, launching it and trying both manually and using MechJeb to get this thing into orbit. And even MechJeb couldn't do it. The simplest explanation here is that your lifting stage just doesn't have enough power to get this thing to orbit. The craft starts with a TWR of 1.05 at liftoff, which is barely enough to get off the ground. In fact, it took several seconds to get off the ground, which just burned fuel. Both manual flying and using MJ, I started the gravity turn at 100 m/s, and this is where things really went wonky. For myself, flying manually, I couldn't get this thing above 20km without it flipping. I checked all the parts, and I checked the fuel drain, and all that. It simply would not stop flipping. So I added a fairing to the top of your craft, just above the reaction wheel you've got in the middle of this thing. And then it couldn't fly because it was too heavy. The fairing gave it aerodynamics, which it desperately needs, but it was just too heavy. I let it run for a few seconds, and it eventually got off the ground...but wasted half the fuel in the first stage to do so. After that happened, I removed the fairing and launched this thing with MechJeb's Ascent Guidance. Again, TWR at launch is 1.05, and the gravity turn was started at 100 m/s. Which, coincidentally, was at about 3500m. You should reach 45 degrees somewhere in the neighborhood of 10km, but even MJ didn't hit that until about 19km. And at 20 km, she started to turn over 45 degrees. Which isn't all that bad, but with TWR was still under 2 at this point. At 22.5km the first stage burned out and the boosters on the side ejected. TWR dropped to 0.6, and for the rest of the flight it never got above 0.65. She reached an Ap of 38501m, at which point she started to come back down to Kerbin. Even with MJ flying, it would not get into orbit. My first suggestion is to redesign the lifter stage and add some thrust/power there. The craft simply does not have enough juice to get off the ground and get to orbit. My second suggestion is to ask why you have a large reaction wheel in the middle of the craft? Normally, reaction wheels (from what I've seen) go near the engines to use their thrust to help with turning. I'm not saying where you have it is wrong, I'm just questioning why.
  16. Hello, Yesterday I was trying to launch with a proper gravity turn. My vehicle was a mk2 shuttle with an external tank and its TWR was a little low after the separation of SRB’s (about 0.8-0.9). However I noticed that the AP continued to rise even with such a low TWR. I then continued with a launch profile where I tried to keep the AP within a minute away. I had the TWR in about 0.9-1.1 during much of the ascent. All the time my AP was rising. I assume this is because as I increase my horizontal speed the ground “falls” away from me even if my TWR is below 1.0. Is this the way it works? Anyway, I got a stable orbit around 95km but I was wondering that such a low TWR during a ascent is probably not the most efficient way of launching (previous test run with about 1.5 TWR gave a 250km orbit). What kind of ratio should I aim at after the separation of SRB’s? Even if it wasn’t the most efficient profile it was a real pleasure getting a nice orbit with such a low TWR! And if nothing else, it had me cracking my brain for the rest of the evening, so all in all a massive success!
  17. By uncontrollable, do you mean that it just tips forward/backward on launch, or it just spins out of control when you are in the atmosphere? If it's the first one, you could try rotating the engines on the actual shuttle piece towards the center of mass, as said by Cantab, but if that doesn't work for some reason or is just too hard to get working, you could simply just mount two shuttles on either side of the big fuel tank like this: This works quite well, but is pretty cursed and might not satisfy you if you're trying to build one similar to or a replica of the American space shuttle. If it is the second thing, it might be caused by there being too much weight at the top of the craft, which you can fix by simply doing a steeper gravity turn, adding more fins to the sides of the orbiter, or maybe both if one doesn't fix it. Again, adding fins might ruin the American-space-shuttle feel your going for, but do remember that the space shuttles were some of the hardest to fly spacecraft ever made, and you might not get the hang of the art of space shuttling on your first few goes. Hope that helped, Jaq
  18. I've been playing a bit of RP0 lately, and I am having a bit of trouble figuring out how quickly I should make my gravity turns. I especially have trouble with low TWR upper stages, such as ones using an RL10. Does anyone have a heuristic for doing gravity turns that could apply here?
  19. Which TWR is "right" depends on a lot of factors, including how you like to fly and what sort of payload you have. In general, you never want to go higher than 2.0, and usually no lower than about 1.2. The optimal rocket design changes quite a lot based on the TWR. If you have a very "draggy" payload (which most of your rockets look to be-- you've got a lot of flat surfaces, these are not very aerodynamic), then usually a lower TWR tends to work better, at least for the first several kilometers of ascent. This is because a high TWR causes you to go too fast when you're still too low, so you're wasting all your fuel trying to shove a draggy thing through thick soupy atmosphere. Taking off a bit more slowly, to keep drag down, may help. (Normally, the solution people go for is to make their craft more aerodynamic and then raise the TWR, which is more fuel efficient. But if you have an awkward payload that has to be draggy, you may have better luck starting off a bit slower.) In general, the most efficient (and stable) ascent path is called a gravity turn (that's a good term to search the forums for, if you'd like to read about it). The basic idea of a gravity turn is that you nudge the craft just a little bit eastward, practically right off the pad... and then you just set SAS to hold all the way up. No steering needed, you're just going all the way, as your ship gradually and naturally pitches farther and farther eastward as it climbs. Just how much of an initial "nudge" you should give it is the tricky part, of course. There's no one right answer, because it depends on your TWR and how aerodynamic you are. But there's a fairly straightforward way to find out: Launch to the pad. Take off! Immediately upon lift-off, pitch a small amount eastwards. (Just take a guess, as to how much.) As soon as you do that, set SAS to hold Don't do any further steering. The only time your hands should touch the controls is to jettison empty stages when the time comes. Take a note of what your trajectory is like when you reach an altitude of 10 kilometers. Specifically, how fast are you going? what angle are you pitched at? Ideally, you should probably be pitched roughly 45 degrees at that point, and traveling something like 300-400 m/s. If (at 10 km) you are going too fast, or pointing too vertically: This means you didn't pitch quite enough in step 3. Revert to launch, and repeat, and pitch it a bit more this time. If (at 10 km) you are going too slow, or pointing too horizontally: This means you pitched too much in step 3. Revert to launch, and repeat, and pitch it a bit less this time. Keep repeating steps 2 through 7 until you're going about the right speed and angle when you're at 10 km. At this point, you're in the pipe and probably going to space, as long as your fuel holds out. The above is only a very rough rule of thumb, but I've found that it works pretty well for most people most of the time, and at least is a pretty good starting point for flying your ship. Really don't do that. Very very fuel inefficient, and will waste scads of dV. That's also very inefficient, and likely to cause control problems, as you have no doubt discovered. The moral of the story is: You want your rocket to be traveling at all times. Never point more than just a couple of degrees off while thrusting, if you can help it.
  20. So, when I look at the Delta-V chart, going into LKO must "use" 3400 m/s of Delta-V. But me when I get to orbit I "use" approximately I use at least 4200 m/s of Delta-V. I know it's quite impossible to do as the Delta-V chart say but I find that I use too much Delta-V for LKO and I think that the problem is from my gravity turn. So do you have some tips to do an efficient gravity turn ? Thank you Fly safe
  21. The math is a bit tricky, so the best way to test this is empirically. I've done both constant altitude landings and constant retrograde landings, and constant altitude landings are more efficient. In a similar fashion, constant altitude ascents are more efficient. And for some reason, ascents are a lot more intuitive for me, so maybe the following explanation will be sufficient: For an ascent on an airless planet, the only thing that matters is horizontal velocity, since you don't need to climb above anything. (Assume that you start from a mountaintop or something, for the sake of argument. Obviously this will be different if you're in a canyon and you need to climb out of it). However, for the sake of argument, we also assume that altitude cannot be lost at all - it must be at least the height of the launch. Then the key will be to gain horizontal velocity as quickly as possible. The earlier you gain horizontal velocity, the more effective the later segments of the ascent will be, because of the Oberth effect. This means that you want to be burning as horizontally as you can for the entire ascent. And that means burning at an angle to prograde, just enough to counteract gravity, while the remainder of your thrust pushes you horizontally. If that's not enough to convince you, here are some screenshots of a constant altitude vs. gravity turn ascent from Mun. (Gravity turn is the inverse of a constant retrograde suicide burn) Starting point: 1843 m/s of delta-v remaining. Constant altitude ascent In 9km - 4.3km orbit, 1274 m/s left, 569 m/s of delta-v expended I use MechJeb's gravity turn utility for the gravity turn ascent. In 6.3km - 5.7km orbit, 1264 m/s remaining, 579 m/s spent In conclusion, the constant altitude ascent let me reach a higher orbit using less fuel, so it seems more efficient.
  22. Forgo the gravity turn. Just luanch straight up and turn right.
  23. so, when you mentioned that you couldn't get enough fuel for a rocket "bigger than a cockroach", i assumed you were using minimalistic rockets with a small command pod and nothing else. that you were launching 20-30 tons rockets. You are launching stuff with multiple mammoths.... you should be able to put into orbit many tens of tons with each launch. Maybe you are just trying to put too much payload into orbit anyway? do you do the gravity turn manuever? especially with rockets so big, you should start turning eastward at around 50 m/s, and reach 45° inclination around 500 m/s for maximum efficiency. even if you botch it somewhat, though, it's not a big deal, you lose 100-200 m/s maximum. You need to botch it badly to lose more. Another thing to check is the TWR: if it's too low (say, 1.2 or something similar) the rocket will lift very slowly, and you'll lose a lot of fuel hovering there (it's called gravity drag). But, most important, I see that the Trüffelschwein 1 only has 2400 m/s before the fairing is removed. Assuming the fairing contains your payload, of course you can't orbit, it should need 3400 m/s on a well-optimized launch. The 5 flips because you have a huge payload with terrible aerodinamics. It would need a huge fairing, but it's still very draggy. Really, that kind of very large payload is a nightmare. I launched one that big a couple months ago, and it took me a day of trying, and i'm good at this game. So perhaps what I can suggest is, take things more calmly, you are trying to put the cart before the horses. Get good with simple ships first. Try maybe with basic designs like this before you try the really huge stuff. Huge stuff is way more difficult. From what I can see, you started the game and immediately went for the biggest, most showy stuff. It's like someone trying to learn to drive and picking the fastest racing car.
  24. So, your real problem here isn't the Vernor engines-- it's that your craft is not aerodynamically stable. When you're taking off in the thick soup that passes for an atmosphere on Eve, aero forces are king; they're so large that they swamp everything else, and a few Vernors wouldn't help you even if they were working properly (which they won't be, at those high pressures). The problem with flipping rockets is basically the same problem as if you try to throw a badminton birdie with the "feathers" end forward: the center of mass needs to be in the front. This is a fairly common problem with Eve landers. You don't want the ship to fall over when it's standing on the surface, so for stability, you generally want it to be low and squat, with the center of mass as low as you can make it. Unfortunately, that's precisely the opposite of what you want for stable flight when you're ascending back to orbit: to climb up out of the atmosphere, you want tall, and skinny, and as top-heavy as possible, with the CoM near the top of the rocket. (Tall and skinny to reduce drag; high CoM for aerodynamic stability.) Adding fins to the bottom of the rocket can help... but the effectiveness of fins is directly proportional to how far behind the CoM they are. So if you have a rocket with a CoM down near the bottom, adding fins on the bottom isn't really going to help. So, what can you do? Well, a few things. Don't make your lander too low and squat. The taller, skinnier, and more top-heavy you can make it for ascent, the more efficient and stable it will be. It can't be too skinny and top-heavy, of course, because then it would fall over when you land, which would ruin your whole day. But don't make it any lower or squatter than it has to be. Make sure the front (top) of your craft is as streamlined as possible. Nice and pointy, avoid anything draggy up there. Don't start your gravity turn too soon. The hardest, most grueling part of an Eve ascent is those first few kilometers climbing through the soup. By the time you get above 11 km or so, the atmospheric density is down to Kerbin levels and it's not so bad; but those first 5 km or so are just murder. During that part of the ascent, you're not trying to build up lateral speed for orbit, you're just trying to muscle your way vertically out of the soup as fast as you can. So here's my advice: For the first few thousand meters of ascent, set your SAS to "hold mode" and don't try to turn at all, just climb perfectly straight up. Here's why that helps: In "hold mode" when the navball is set to "Surface", what SAS will do is point you directly straight up. SAS has faster reflexes than you do, so it'll do a pretty good job. If it can hold you very close to perfectly straight up, then that means that even if there is some instability in your design, hopefully your engine gimbal, control surfaces, and reaction wheels can compensate for a while. Furthermore, precisely because that part of ascent is so brutal, you're gonna burn a lot of fuel, meaning that your big heavy boosters down on the bottom of your craft will be dumping mass and getting staged away-- which will raise your CoM and make you more stable. Hopefully, by the time you've climbed above 10 km, your CoM will have moved upward enough that your craft will be more stable and you can start your gravity turn without flipping out. Use active fins. Use fins that are active control surfaces, such as the AV-R8 winglet. These really help a lot with aerodynamic stability. However, be aware that until/unless your CoM raises high enough above them, they're not going to help you much, thus the advice above about not starting the gravity turn too soon. Climb fast, but not too fast. The higher your TWR and the harder you accelerate, the lower your gravity losses will be, which is generally a good thing. However, if you go too fast too soon, while you're still low in the atmosphere, then aerodynamic drag will build up really fast, and you can end up losing more to aero drag than you save on gravity losses. Furthermore, if your craft is aerodynamically unstable for the first part of ascent, then hitting too much drag too soon can overpower SAS as it tries to hold . So, what's the right balance? Skipping over a bunch of math, basically it works out that the optimally efficient vertical ascent is when you're traveling at terminal velocity the entire time. What that means is that you want a (local Eve) TWR that stays as close as possible to 2 while you're on the initial vertical part of the ascent; don't go higher than that. Since Eve surface gravity is 16.7 m/s2, that means the ideal acceleration power of your rocket during that part of ascent is double that, i.e. 33.4 m/s2. Lower than that, and you'll be wasting fuel to gravity losses. Higher than that, and you'll be wasting fuel to aerodynamic drag, and also making your instability problems worse.
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