Zhetaan

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  1. Here's a picture. That's in the tracking station; you find it with the 'Object Info' button. Here's some more information about it.
  2. @Streetwind, @PrvDancer85, @Starman4308, @Spricigo: Here's the update. I kept getting weird numbers when I tried to fit the curve. My initial guess values tended to be off a bit--which I expected from trying to use a quadratic fit on a cubic spline--but when I tried to fit a cubic, I started to see values that didn't make any sense, especially for Eve. Either KSP or Unity is doing something odd with the spline, and since I don't need to bother figuring out the equation when I want obtainable data points, I decided to get empirical data instead. That means that I strapped every engine in the game onto a sandbox monstrosity, turned on all the cheats, and went to every planet with an atmosphere. Duna has no sea-level terrain; I believe the lowest elevation is about 170 metres but I don't know exactly where it is, so I decided to use a spot at about 270 metres. Cutoff pressure is taken from the configuration files. Normal LFO engines: Engine Vacuum Duna Laythe Kerbin Eve Cutoff Pressure (atm) Ant 315.0 299.4 160.0 80.0 0 3.0 Spider 290.0 288.1 272.5 260.0 114.1 8.0 Twitch 290.0 287.4 266.1 250.0 83.8 7.0 Spark 320.0 316.4 289.5 270.0 88.9 7.0 Reliant 310.0 307.1 278.9 265.0 88.2 7.0 Swivel 320.0 315.7 268.9 250.0 48.4 6.0 Terrier 345.0 327.7 173.4 85.0 0 3.0 Vector 315.0 313.7 303.5 295.0 193.3 12.0 Dart 340.0 335.3 303.6 290.0 230.0 20.0 Thud 305.0 303.1 286.6 275.0 139.7 9.0 Mainsail 310.0 308.4 295.8 285.0 147.8 9.0 Skipper 320.0 317.4 297.2 280.0 57.4 3.0 Poodle 350.0 332.7 160.2 90.0 0 6.0 Twin-Boar 300.0 298.7 289.1 288.0 147.6 9.0 Rhino 340.0 331.1 252.9 205.0 0 5.0 Mammoth 315.0 313.7 303.3 295.0 193.3 12.0 Solid Rocket Boosters: Engine Vacuum Duna Laythe Kerbin Eve Cutoff Pressure (atm) Flea 165.0 163.4 150.2 140.0 28.3 6.0 Hammer 195.0 193.4 180.2 170.0 57.4 7.0 Thumper 210.0 207.7 188.9 175.0 35.0 6.0 Kickback 220.0 218.4 205.4 195.0 66.7 7.0 Jet Engines: Jets operate differently from other engines. Their Isp is always the Kerbin sea level value; the thrust varies with the velocity of the engine and a curve called atmCurve which is distinct from atmosphereCurve. Of course, there needs to be enough oxygen entering the engine to keep it from starving for the lack, but technically, the Isp on Eve or in space is the same as on Kerbin. Utility, Odd, and Other Engines: Engine Vacuum Duna Laythe Kerbin Eve Cutoff Pressure (atm) Nerv 800.0 759.3 375.7 185.0 0 2.0 Rapier 305.0 303.1 283.3 275.0 139.7 9.0 Puff 250.0 241.4 165.5 120.0 0 4.0 Dawn 4200.0 3927.2 1480.9 100.0 0 1.2 Sepratron 154.0 151.6 131.5 118.0 22.6 6.0 Launch Escape System 180.0 178.7 168.2 160.0 69.7 8.0 There were a few interesting discoveries here. One thing to note is that, in terms of performance, the Vector really is one engine from a Mammoth cluster; everything is exactly the same. Another is that the Spider is much, much more capable than the Ant in terms of atmospheric operation. This by no means is an assertion that the Spider is a valuable launching engine, but it does mean that you could probably make some fun glider drones with it, and these things would work on Eve, too--the Spider can operate at some truly high pressures. The Hammer cuts off at a higher pressure than the Thumper; if you are silly enough to take SRBs to Eve, then take Hammers over Thumpers because Thumpers at Eve sea level are operating too close to their limit, and the Isp values reflect this. The Dart is the only engine that operates at 15 atm; if you're even crazier than the one who took SRBs to Eve, then the Dart is the only thing that works at Jool's datum (zero altitude point). I don't know whether any rocket can climb out of that far down Jool's gravity well (pressure may be a problem before you get that low anyway), but the Dart is the only thing that can try.
  3. kOS Help?

    @ATLUTD_741: You typed your program into the command line, not the text editor. The text editor is the box under the terminal on your second image. You created a new file, ran all of the commands one by one at the command line rather than typing them into the text editor, and then saved the empty file. When you tried to run the program, there was nothing in it to run. Technically, at least, you did run your first kOS script; it was just a null script. Does extreme minimalist programming count? Edit: Ninja'd.
  4. @PrvDancer85: Sea level Isp depends on two things: the engine's configuration file and the atmospheric pressure. The sea level pressure for each body is: Eve: 5.0 atm Kerbin: 1.0 atm (naturally) Duna: .0666667 atm Laythe: .6 atm (its gravity is .8 g; apologies, @Streetwind) Jool: 15.0 atm (not that you would want to go to 'sea' level, and no rocket will have usable thrust that low, but the value exists) I picked a selection of popular first-stage engines (and the Poodle for comparison) and pulled the atmospherecurve values from their configuration files (on the wiki, which may not be completely up-to-date, but it's close enough for now). Mammoth: 0: 315 1: 295 12: .001 Twin Boar: 0: 300 1: 280 9: .001 Mainsail: 0: 310 1: 285 9: .001 Dart: 0: 340 -50 -73.71224 1: 290 -21.23404 -21.23404 5: 230 -10.54119 -10.54119 10: 170 -13.59091 -13.59091 20: .001 Swivel: 0: 320 1: 270 6: .001 Reliant: 0: 300 1: 280 7: .001 Poodle (for comparison): 0: 350 1: 90 3: .001 With these values, you can either use a Unity floatcurve editor to get exact intermediate values, or you can take a few guesses and interpolate for rough intermediate values. The first two values for most of these engines give an exact Isp for vacuum and Kerbin sea level; the third is the effective cutoff pressure in atmospheres. The Dart has a more complex curve because it has to maintain near-constant Isp over a variety of pressures, that's mathematically tricky, so it has extra numbers. These are all cubic Hermite splines, as has been said (@Starman4308), but I'm not at the right computer for that. For values between 0 and 1, the curve is usually linear enough that a linear fit will work, but for values greater than 1 (Eve), the curve is no longer linear enough, so I used a quadratic fit instead. However, that is not necessarily the best fit, especially for values close to the cut-off pressure (Eve's surface is usually in the suspect zone). The Poodle has the most extreme drop in Isp and no clamping on the nodes, so its curve is, in a word, crazy: I tried a logarithmic fit for it as well. Though it gave a better curve than the quadratic, the intermediate values were different enough that I chose to use the average value and indicated the approximation with the tilde (~). It should also be noted that the Dart uses a clamped curve, which is a lot more difficult to draw on my one-lung work computer, so you should probably consider both the Duna and Laythe values to be suspect; unlike other engines, however, the Dart has a defined value for Eve sea level, so that value, at least, is exact. Note further that the Poodle drops out at three atmospheres; it has no significant thrust on Eve. Note further than that that Duna's atmosphere is almost negligible; vacuum Isp can be approximated reasonably as sea-level Isp for any first-stage lifter. Second-stage and dedicated vacuum engines probably have more significant differences. All stock engines have negligible thrust at 15 atm; Jool take-offs are just as impossible as Jool landings. I'll see about doing some more work on this at home later today. Engine Vacuum Duna Laythe Kerbin Eve Mammoth 315 313.7 303.1 295 203.6 Twin Boar 300 298.8 288.4 280 166.7 Mainsail 310 308.4 295.3 285 161.4 Dart 340 335-336 307-308 290 230 Swivel 320 316.7 290.1 270 56.7 Reliant 300 298.9 288.9 280 123.8 Poodle 350 328.2 176.8 90 <<.001 EDIT: I tried this with a spline interpolator and was able to refine the values somewhat. Everything for which a quadratic spline was sufficient changed at the hundredths or less; the values given in the table stand. The Poodle was very close at Duna but I revised by about ten for Laythe. The interpolator I used didn't allow me to use tangents, so I need to wait until later to better refine the values for the Dart.
  5. @Just Jim: I thought the telepathy-vision-dream sequence was very reminiscent of the SSTV signal from Duna. In any case, it was quite nicely done--I don't even want to guess at how much time you had to spend on it to get it right.
  6. How to make KSP more accurate?

    Have a look. The short version is that it boosts Tylo's and Vall's orbits to break the resonance (and attendant perturbation) and changes Bop's orbit to retrograde.
  7. New Player / Tips (Thanks!)

    @fisune: Also, welcome to the cozy little family. The community here is extremely supportive, and if there's anything you seek to know about how things can be done, please ask. It's true that doing just about anything in this game is extremely difficult, but it's also true that finally seeing it accomplished is extremely rewarding. Per ardua ad astra, and all that goes with it.
  8. @JEB'S DESTINY: @Streetwind has the right of it, and I will only add that when we say 'figure 8', don't expect it to look much like the numeral with the two loops being of roughly the same size. It's a very lopsided 8 where the orbit crosses itself very near to the Mun. About 90% to 95% of the figure is Kerbin's loop, and the Mun gets the tiny bit left over.
  9. Your Skipper only runs for 38 seconds. That's not really enough time to justify the engine; I'd suggest switching it for a Poodle. Usually, it's worth trying to get about two minutes of burn time out of a stage. Assuming that the previous stage is enough to get you to orbit, a Poodle might even give you too much dV for munar transfer--which is a good thing, because it also gives you a lot of margin and reserves for picking a perfect landing spot. You have monopropellant but no attitude jets that I can see; it's just along for the ride and that's a waste. If you do have attitude jets, why? If you get rid of the monopropellant tanks; drain the monopropellant out of the lander can, as well. It's not that big a deal but why pay for it if you won't use it? The high-drag transitions at the top of the rocket are going to cut down on your ascent efficiency a lot. Using adapters or switching to all 2.5m parts would help that. On the other hand, if you have access to fairings, that would work just as well and prevent your lander from being so tall as to tip easily. On the gripping hand, you could run the same mission with all parts on a 1.25m stack, but I got the impression that that is what you tried before and it did not work out too well for you. If you do have fairings, you can do things that don't really make intuitive sense. For example, you can surface attach the small FL-T100 fuel tanks after flipping them up on their sides (so that you join the added tank to the centre tank by the flat face--don't try to join it on the curved face); you can fit three of them around a central tank and get four times the fuel for nearly the same footprint as one tank--but ploughing that through the atmosphere is a pain, so definitely use fairings. Definitely consider switching out the boosters for Thumpers. If that gives you too much TWR, then reduce thrust and run them for longer. Keep some winglets or fins; you shouldn't need those big swept wings for that rocket, but you absolutely will need something. Others have said to consider exchanging the lander can for a Mk. I Pod, and that's something to seriously consider. Since the pod (and utterly necessary parachutes and shielding) is what needs to come back, you may want to consider putting all of the science gear in the landing but not the ascent stage, and letting the ascent stage consist only of the actual Kerbin return package plus a small engine and enough fuel to return only that package. Do you have the 2.5m service bay? It can fit all of the science experiments you brought and save you both height and drag, and you can put it in the section with the landing legs to be staged away once you are ready to make your Kerbin return.
  10. That's funny. I thought he was in Los Angeles. That's quite the craft. What did you use for the air screws?
  11. @BlackWing Pilot: If you decide to use Alex Moon's planner, note that it gives both date and time of departure and a set of two angles called the phase angle and the ejection angle. These angles are better understood with a visual: this is Olex's interplanetary calculator, from which part of Alex Moon's planner is derived. You'll need both of them to be correct in order to get good transfers. The phase angle has to do with the relative position of the origin planet and destination planet, and is the reason that transfers can only occur during 'windows'. If you leave your origin planet outside of the window, then while you will often reach the destination planet's orbit, the destination will not be there when you do. The ejection angle is related to the fact that you begin your interplanetary trip from an orbit around a gravitational body and so your departure point must move a little to account for the way that gravity can change your flight path on your way out of the origin's sphere of influence.
  12. The Ultimate Challenge

    I second this. While there is something to be said for boosting to Eeloo first and then setting up a bi-elliptical transfer to Moho, in the interests of time, tedium, and overall fuel savings, you're better off taking Eve-Moho-Eve first. Also remember that transfer windows are least frequent between planets that are next to one another in their orbits; it may make more sense to skip around the system a bit.
  13. Quite true. But you came to the right place, so let's take another try. First, orbital mechanics and manoeuvring is confusing; everything you thought you knew about motion goes right out when you put it in orbit. When I was learning this, I found it hideously frustrating, but the trick sometimes is to step back and watch someone else do it. Set some appropriately-themed music.... ... And let's see what we can find. If you want better or different tutorials, then you can look here. Remember that some of these are old enough that the game mechanics have changed; for orbital operations, however, anything from 2015 and later is okay. A lot of the stuff from earlier is good, too (they didn't change the Mun's orbit or anything like that) but SAS has changed its behaviour a few times during KSP's development. If you're committed to learning how to do this using the various hold modes, then stick to the later tutorials. If you want to learn how to do this stuff by hand as well, then take a look at some of the older stuff. I found a video series that plays the in-game tutorials (from version 1.1, but nothing has changed in space between 1.1 and today) and it shows the same behaviour that you were complaining of: I linked it at the end of the burn, but you can clearly see that the node hold switches to stability assist when the remaining burn goes below 1.0 m/s. The manoeuvre node also flies off the navball to the right; this is both normal and expected. Even after following the instructions, this video also shows that the burn, as executed, didn't quite lower the periapsis so much as was necessary; to correct this, the player used retrograde hold and that is perfectly acceptable. Later on, during the actual landing, it shows what happens when using too much retrograde hold; the ship stopped descending and began to climb, and the SAS forced the nose to point down. This was not a destructive problem because the vessel was high enough off the ground that it did not crash, but it did waste fuel. And no, I do not know why the navball markers show up in black in this video; it doesn't affect the function.
  14. I'd be guessing as to the exact relationship, but the idea is that as you take contracts but don't complete them, there's a law of diminishing returns. Note that 'available' contracts for you right now is not 15, it's zero, and that implies that the diminishing return begins to assert itself when you're about halfway to the average. I have not tested this myself (hence the guessing), so that may be completely wrong. If you were to set AverageAvailableContracts to 20, it could be that you would then start to see offers go down at about 10 but would be able to squeeze 30 contracts total out of the system, or it could be that you would only see diminishing returns at 15 contracts but could max out at 25. Or it could be something completely different; as I said, it's not well-tested. The only contracts I've seen for more than six tourists are mod contracts. That's another reason to look at Contract Configurator--specifically, Tourism Plus. Take a look at the screenshot in its first post and decide whether that interests you, but the important part is that you can eventually get contracts for up to 50 kerbals at a time. It also has some other interesting contracts such as the Space Camp, where you take 13 tourists and three instructors into orbit for a month and a half. When you're done, three of the tourists join the space program. Of course, if you want to put together some kind of large spaceliner for a mission to Jool and don't want to waste the construction on six tourists, you can always take multiple Jool tourist contracts and send everyone together ... assuming that the game lets you have more than one at a time. If not, you know where to change the setting. No, it means that having two stations is necessary to get the maximum chance for an expansion contract. With one station, you can still get expansion contracts, but there's a lower chance of getting them. I'd have to look at the rest of the file, but I think that if you have only one station, it tends to offer contracts to build a second over expanding the first. I'm not certain whether the game requires a station to be marked as such in the Tracking Station--I suspect so, but I've been surprised to get a World's Firsts reward for station construction just from docking a lander to a transfer vehicle while in Kerbin orbit; it seems that the game automatically thinks of a station as having a docking port, antenna, power generators, and at least a six-kerbal crew capacity (you may note that these requirements are always present in station-building contracts). I do know that Tourism Plus won't give station visitation contracts for tourists unless the station is categorised as such in the Tracking Station.
  15. @ej89: The cake is a lie. So is the 'unlimited contract' feature of Mission Control. @nightingale's Contract Configurator will let you have up to 18, I think (and it offers some other features that you may like, so have a look), but I believe what you'd really like is found in Gamedata\Squad\Contracts. It's a file called Contracts.cfg, and near the top is a line that says 'AverageAvailableContracts = 10'. Change this to what you like. Just be mindful that there is a limit for a reason, so watch out for issues that may arise from raising the limit to something absurdly high.