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Everything posted by Leganeski

  1. Reaching Kerbin orbit at 7.6x scale requires achieving a surface velocity of about 6200 m/s. No matter how much you optimize the ascent profile, there's no way to get around the fact that orbital velocity is fast. Jet engines are efficient, but their downside (apart from requiring oxygen) is that their thrust starts decreasing beyond a certain speed dependent on the exact engine, and eventually drops to nothing. The Panther engine, for instance, completely loses thrust at Mach 3.5 (≈1100-1200 m/s). Other less efficient jet engines such as the Whiplash or RAPIER are better, continuing to function until Mach 5.5-6 (1800-2000 m/s), but that's it. At stock scale, where you only need to achieve a surface velocity of 2100 m/s, jet engines can take you almost all the way there, and you can get away with having only a little bit of rocket power that pushes you the rest of the way into orbit. Since you're so close to orbit, centrifugal force reduces the TWR requirements considerably, so there are a lot of options: nuclear engines to avoid the need for oxidizer, small LFO engines for lower dry mass, or really anything with enough Δv. At 7.6x scale, the situation is completely different: even 2000 m/s is nowhere close to orbit, and you need to accelerate the remaining 4200m/s (or probably more) with rocket power alone, while fighting drag and gravity without much help from the curvature of the larger planet. The Δv requirements for the one stage practically necessitate nuclear engines, but the TWR requirements (something like 1.0-1.5 g) are difficult to achieve with the stock NERV, especially if you're also using it to carry stuff like wings and payload. There's a reason why SSTOs have never been built in the real world, and the comparatively limited selection of parts in KSP makes designing one even harder. Your 4560-km-radius Kerbin is not quite as difficult to orbit as the 6378-km-radius Earth, but I don't think that this minor decrease in orbital velocity is enough to make the challenge doable without a whole lot of trial and error, and a very small payload fraction. Edit: As @Lt_Duckweed points out, I was neglecting the possibility of continuing to remain at low altitude during most of the ascent, which would allow the plane to use lift to lower the TWR requirement to manageable levels. This requires very precise control over both altitude and angle of attack to maintain just the right amount of lift, and generates a ton of heat at high velocities. However, the somewhat unrealistic wing parts in KSP take zero damage from any temperature below 2400 K, so they might just be able to survive. I have never been successful flying an SSTO like this: either I encounter too much drag and quickly run out of fuel, lose control of pitch and spiral into a crash, or make too sharp of a turn and break my wings off. It's definitely possible, though, and I imagine that an autopilot mod would help reduce the risk of all of these problems.
  2. Not that I know of, but here are the angles I calculated. (*The starred angles vary considerably due to orbital eccentricity.) From Kerbin Moho: -252* (i.e. Moho is 252 degrees behind Kerbin, or equivalently 108 degrees ahead) Eve: -54 Duna: +44 Edna: +75 Dres: +82* Jool: +97 Lindor: +106 Eeloo, Hamek: +109* Nara: +114* To Kerbin Moho: +76 (i.e. Kerbin is 76 degrees ahead of Moho) Eve: +36 Duna: -75 Edna: -238 (equivalently +122) Dres: -330* (+30*) Jool: -769 (-49) Lindor: -2011 (+149*) Eeloo, Hamek, Nara: none (the optimal angle varies by more than 360 degrees over the course of the planet's eccentric orbit, and even a 180 degree misalignment is relatively cheap to correct because Kerbin completes many orbits during the transfer) If you want transfer angles for the moon systems as well, let me know and I'll work on making a table.
  3. The new bodies look fantastic, and I think that Windswept's terrain is a lot more interesting now! Are Canyon and 106030 supposed to be tidally locked? (Currently, they aren't locked but their config files don't specify rotational periods, so they inherit Moho's rotation rate from the template.)
  4. Frontier's orbital period is 6 years 297 days (2853 Kerbin days; 1786 Frontier days; 61617827 seconds). Kronometer will let you change the calendar, but this mod doesn't have a patch for it, so you'll need to write your own configuration file if you want the year length to match the orbital period. According to this more recent post from March, Frontier is indeed still intended to have oxygen:
  5. Congratulations on the release! There are so many unique and interesting planets that I can't believe they all fit in one system. Here is an (unofficial) table with all the delta-v information. (This may contain minor spoilers if you haven't yet looked at the physical parameters of all the bodies.)
  6. Almost. Most* terrain only scales up by a factor of 2.5 instead of 4, so low orbits around airless bodies will still be closer than expected. This means that getting to orbit takes slightly less than double the delta-v, and transfers usually take very slightly more. By "slightly" I mean less than 0.5%, so you can probably ignore the difference without issue. *Gilly, Dak, and Tam keep their shape, so their terrain is scaled up by the full factor of 4. However, they aren't exactly the places where you have to worry very much about delta-v.
  7. On a perfectly round airless body, your reasoning would be correct. However, Kerbin is neither of those things, and in particular its atmosphere causes a lot of imprecision. Although the scale factor increases by 4, the atmospheric scale height only increases by a factor of 1.1-1.2x, and the low orbit altitude increases by 1.5-1.6x. This means that delta-v losses from both of these sources scale up by significantly less than 2.
  8. Hello and welcome to the forums, @destroyerofGPUs! This mod is supposed to delete the Kerbol system, so you are correct that something is probably wrong with the installation. Are you sure that you have Kopernicus Expansion working correctly? Also, AVP is a visual pack specifically for the stock system and OPM, so it will not work on other planet packs. Avalon has its own EVE and Scatterer configs, so external configs like AVP are not needed.
  9. I don't think this is directly possible, as KSP is hard-coded around the Sun being at the center of the universe and having an infinite SOI. However, what you can do is give the Sun all the properties (including the external name) of the star that you actually want at the center, and create a new star orbiting it which has the properties of Kerbol. The stock planets can then be moved to orbit the new "Kerbol" star. Every non-Sun object has to have some kind of orbit, but it is possible to make the orbit line invisible and the orbital period extremely long, which effectively makes the object stationary.
  10. It's not a map, but I did make a delta-v table for transfers between all pairs of currently implemented objects (not just those to or from Revan). (The table is now up to date as of version 1.3.1.)
  11. Interesting! Those temperatures seem perfectly reasonable to me given their conditions; I was asking because the 1.1.1 download has atmospheric mean surface temperatures of 231 K for Perbi and 109 K for Heyu.
  12. These maps and atmospheres look good, and the system layout seems quite interesting so far! I only noticed a couple things at first: Canyon, Heyu, and 106000 don't have their Scatterer atmospheres show up in game. This seems to be because Canyon isn't in the planetsList, Canyon's and Heyu's Scatterer configs have names of Duna and Eve respectively, and 106000 doesn't have a folder at all. Is the version you just uploaded to Spacedock a test version? Perbi and Heyu have liquid water oceans but surface temperatures well below 273 K. It's possible to manually adjust specific parts of the temperature-pressure curve in OhioBob's atmosphere calculator to add corrections for things like tidal heating, so would it be helpful to raise the temperatures of those atmospheres just near the surface?
  13. For tanks, I use Simple Fuel Switch, which allows all LFO tanks to be converted to LF for pretty much exactly this purpose. If that is not an option, I usually use Mk3 fuselages, because it lowers part count a lot and the lower mass ratio doesn't actually reduce Δv all that much. I try to keep TWR in the range of 0.15 - 0.4 g (i.e. 7 - 20% of the craft's total mass is NERVs). I generally accept burn times up to about 1/6 of the orbital period at the current altitude. If the planned maneuver is larger than that, I try a few different approaches: Initially, I try using multiple periapsis kicks. (This usually works.) If the desired trajectory is so much faster than escape velocity that periapsis kicks are insufficient (e.g. Kerbin to Jool with low TWR), I attempt to find a closer large celestial body (e.g. Eve) and begin a gravity assist chain there. If no such body exists, I eject as much as I can and then finish the rest outside the SOI. In my experience, this usually happens when around a relatively small object in a very fast orbit (e.g. Hale from OPM, or Ammenon from Whirligig World), in which case the losses from reduced Oberth effect are minimal. Certainly not all of these approaches will work for everyone, but I would highly recommend Simple Fuel Switch.
  14. In sandbox mode, all experiments (surface deployed or not) have a 0% science yield. In order to change this, you would have to start a new save in science mode and use the Alt-F12 menu to unlock all the technologies.
  15. Hello and welcome to the forums, @rattata21216! These lines need "%" or "@" at the start. Without that, they're giving Gilly new orbital parameters in addition to its usual parameters, rather than replacing them. I'm not completely sure whether this is causing the problem, but my guess is that Principia is somehow mixing up the old and new parameters, resulting in weird orbits such as the one you encountered.
  16. This is correct. However, the data is not transmitted continuously but rather in packets of (in the case of the HG-55) 2 Mits every 0.35 seconds, and each packet consumes 18 EC all at once. This doesn't matter much unless your total battery capacity is less than 18 EC, in which case you won't be able to transmit any packets even if you are generating the full 51.4 EC/s. None, as far as I can tell. I've launched quite a few relay satellites with powerful dishes and less than 0.1 EC/s of net electricity production, but I've never lost control due to one of them running out of charge.
  17. Hello and welcome to the forums, @StavraDev! Surface gravity is generally not affected by the scale factor, regardless of the type of planet. For instance, Kerbin and Earth have the same surface gravity despite being at very different scales. To get the surface gravity of a 1/5 scale planet, you just need to calculate the surface gravity that a real-life planet with 5 times the radius would have. This is not actually caused by the 1/10 scale factor. Jool's surface gravity is indeed lower than what it would be in real life, but this is because the stock KSP system was created without too much attention to whether the densities were exactly realistic. (Eve is 45% denser than the otherwise similar Kerbin, a difference so substantial it would be very hard to explain in the real world.) In order to find out what Jool's surface gravity should be, we could compare it to Saturn. Jool has just over 1/10 the radius of Saturn, which has a mean surface gravity of 1.065 g, so Jool's surface gravity should be slightly higher: somewhere around 1.1 or 1.2 g. Real gas giants never get much larger in radius than that, unless they're rotating quickly or puffed up by heat from a very close star. As the mass of a planet increases beyond about that of Saturn, it starts getting compressed, and nearly all of the new mass ends up increasing the surface gravity rather than the radius. For example, Jupiter has 1.2 times the radius of Saturn, but 2.4 times the surface gravity because it is so much more compressed. Above 10 times the mass of Saturn, the radius actually starts shrinking as more mass is added! The following chart (taken from here) shows the relationship between mass and radius for a range of different compositions. Typical gas giants are near the dotted light blue line, which represents a composition of mostly hydrogen with some helium. To get the surface gravity, divide the mass by the square of the radius. Everything on the chart is relative to Earth, so it should come out in gees. Finally, I might mention that 1/4 real scale tends to be more commonly used than 1/5 in the KSP modding community. (For example, JNSQ's planets were constructed at 1/4 scale, and BDB's rockets were balanced at that scale.) Of course, the scale of your mod is entirely up to you, but choosing 1/4 scale could potentially lead to better integration with other mods.
  18. Yes and yes. Kopernicus is the tool OPM uses to actually add its planets to the game. If you add OPM to an existing save, make sure that you don't have any crafts at Eeloo, or they might get messed up when Eeloo moves to orbit Sarnus.
  19. Putting heat shields on both ends is my preferred strategy for trying to land anything big on any large atmospheric body. In addition to the aerodynamic stability benefits, twice as much thermal protection in case the plane does start tumbling is very helpful. What I tend to do is this: Put both heat shields far away from the center of mass. Wait until the plane slows down to terminal velocity and stops tumbling. Decouple the heat shield on the top. Wait until the plane flips over so that the other heat shield is on top. Decouple the other heat shield. This ensures that both heat shields are released in the direction they are being pulled away from the plane by drag, so that they don't break anything. Sometimes the plane doesn't stop tumbling, making this approach impossible. In that case, I still wait until terminal velocity is reached, but then try to release the first heat shield about 30 degrees before it reaches its highest point in the tumble cycle. This often works, but sometimes I need to reload a few times before getting the shield to leave at the right angle. If all else fails, you could put detachable parachutes on the wings, and decouple the heat shields after the parachutes deploy.
  20. Unfortunately, AVP is a graphics configuration specifically for the stock system and the Outer Planets Mod, so it will might not work on planets from other mods. Thankfully, Kcalbeloh has its own configurations for Scatterer and EVE, so you can install those mods instead and get graphics of a similar quality.
  21. 10x scale Kerbin is nearly identical to Earth in terms of its physical parameters, so getting to Mun is about as difficult as a real Moon mission. Nice job!
  22. There is one relatively complicated technique that will actually reduce your velocity relative to Kerbin: the gravity assist. Two gravity assists at Kerbin, followed by one at Eve, can slow down your speed from 4000 m/s to 3100 m/s. However, if you just want to return a few kerbals to Kerbin, @Cpt Kerbalkrunch's suggestion of using a heat shield is much easier and more effective.
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