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billkerbinsky

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Everything posted by billkerbinsky

  1. I'd think that a realistic model would have the spacecraft go into "safe mode" after a watchdog timer went off. Exactly what safe mode entails would depend on the probe, but it would involve turning off anything that burns a lot of power and periodically waking up to listen for one-way low-bitrate commands from home.
  2. Takes a little while for the diagram to render - maybe 10 seconds? Give it some time... (in any event, it's faster than KSP loading..)
  3. see post #9402 above; the MechJeb developer has access to an early 1.0 prerelease and is working on porting it.
  4. If there's a throttle, it's not an RTG. (Maybe you want a small nuclear reactor instead?) To make an RTG, you synthesize and purify a batch of RTG fuel (usually Pu-238) which by its very nature (an isotope with a particular half-life) decays over time at a known rate, releasing a useful amount of heat which is turned into electricity via thermocouple or Stirling engine or whatever. There's no "on" or "off" switch for the underlying reaction, and if you reduce the amount of energy used, you don't extend the life of the RTG.
  5. lajoswinkler is correct about the temperatures on the inside, but for engine effects you need to model the temperature of the outside. There's going to be some active cooling of the throat and upper nozzle; a common way to do that is to circulate some of the cryogenic propellant through tubes running around the throat and nozzle. Where there is active cooling, the outside will be much cooler than the inside. what I see in the (real engine) picture in #120 above is peak brightness just below the throat. what I see in the KSP picture in #122 is peak brightness at the rim, which is wrong. I'd expect the outside temperature to be cool near the throat due to active cooling, quickly rise to a peak just below any actively cooled area, and then fall off again as you go further down the nozzle. reverse the color gradient and you can make the engine in #122 look more like the one in #120...
  6. Wow, huge bell. Looks like a candidate for a extendable nozzle like the RL10B-2
  7. How about something like what GMail does for multi-select? If you're not familar with it, there's a tick box within each list item. You can build a set of resources by ticking the boxes, or select a single one by clicking in the item outside the tick box. you could use the same sort of multi-select pattern within the transfer window for 1:N and N:1 (and N:M) transfers - select one on your tanker, select all 47 on the asparagus-staged Eve lander, and refuel with less fuss.
  8. I have a hopefully simple enhancement request. All of the stock LF+O engines consume fuel and oxidizer at a fixed stoichiometric ratio; all the LF+O tanks store the propellants in that ratio. It would be helpful if there was a way to move both of them together in that ratio. It would both save time when refueling (fewer clicks required), and it would also make it easier to part-fill a tank without getting the ratios out of whack with each other and as a result possibly stranding LF on one craft and O on the other..
  9. What I find myself wanting is "oh, what a cute maneuver. Let's just use RCS translation and not bother turning first". Particularly for the plane change maneuvers done by the rendezvous autopilot; when it's only a 2m/s burn to fix the plane it seems like you burn more RCS deltaV rotating the ship 90 degrees to normal/antinormal and back again than you would from just doing an RCS translate burn.
  10. See the "Lightbulb" engine in the Atomic Age package: http://forum.kerbalspaceprogram.com/threads/104855-0-90-Atomic-Age-Nuclear-Rockets Mass 20t, Thrust 450 kN, ISP 850-1500s
  11. I'd say. Pu-238 is an ideal RTG fuel, which means that (in our universe, at least) it has a modest half-life (about 87 earth years, or about 300 Kerbin years) which means that would all have decayed on geologic time scales without some process to continuously produce more. I'd expect the only way to accumulate meaningful quantities of RTG fuel is via reprocessing of used reactor fuel. There are a bunch of ways to make it; neutron irradiation of Np-237 requires two trips through a reactor (one to make the neptunium, one to turn purified neptunium into a mix of neptunium and Pu238) with chemical separation after each trip. Thorium reactors reportedly produce it in modest but meaningful quantities (wikipedia says around 15kg per GWe-year).
  12. Yes. An asteroid like 24 Themis with a less-inclined orbit would be interesting as a potential intermediate base location for exploration of the outer planets.
  13. When using the fairings in this package, it seems like one or two of the petals always typically bounce off the payload on fairing jettison. I'm doing the jettison when coasting to apoapsis out of the atmosphere. What's the right way to stage them? In case it matters, I'm using KJR and the Stock Bug Fix modules and a few other things. I'm not using any of the aerodynamics mods (wanted to get used to using fairings when it doesn't matter before making that switch).
  14. I'm seeing the same errors when I attempt transfers with 4.1.3; 4.1.2 worked fine for me.
  15. Is the argument to cos() in radians or degrees? The above script makes sense if cos() takes degrees, but in most (other?) programming languages cos() and sin()'s argument is in radians, and the oscillation you describe is consistent with feeding degrees to a trig function expecting radians.
  16. Just say antimatter requires so much packaging/shielding/monitoring/etc., that you always need to move 1L of "stuff" to move 1ml of actual antimatter around between tanks and engines.
  17. I've seen something similar with a very different set of extensions. BTW I think the Unity "Player.log" file is more useful. When I try to leave the current vessel, I get tracebacks like: NullReferenceException: Object reference not set to an instance of an object at PatchedConicRenderer.OnSceneSwitch (GameScenes scn) [0x00000] in <filename unknown>:0 at EventData`1[GameScenes].Fire (GameScenes data) [0x00000] in <filename unknown>:0 at HighLogic.LoadScene (GameScenes scene) [0x00000] in <filename unknown>:0 at PauseMenu.saveAndExit (GameScenes sceneToLoad, .Game stateToSave) [0x00000] in <filename unknown>:0 at PauseMenu.draw (Int32 id) [0x00000] in <filename unknown>:0 at UnityEngine.GUILayout+LayoutedWindow.DoWindow (Int32 windowID) [0x00000] in <filename unknown>:0 at UnityEngine.GUI.CallWindowDelegate (UnityEngine.WindowFunction func, Int32 id, UnityEngine.GUISkin _skin, Int32 forceRect, Single width, Single h\ eight, UnityEngine.GUIStyle style) [0x00000] in <filename unknown>:0 (Filename: Line: -1) I originally thought it was KJR, but then reproduced it without KJR: http://forum.kerbalspaceprogram.com/threads/55657-0-90-Kerbal-Joint-Reinforcement-v3-1-1-1-15-15?p=1764164#post1764164
  18. The name "DepletedUranium" for spent fuel continues to really bug me as terminologically misleading. It's as if the game called the high point of the orbit the periapsis... Real depleted uranium is uranium with less U235 than usual (under 0.3% U235, vs natural uranium being around 0.72% and enriched being anywhere from 3-4% U236 for reactor grade to 90% U235 for bomb-grade. There are apparently significant size & mass advantages to running a reactor on more highly enriched uranium but (on Earth) it has to be balanced against the proliferation risk. No such contraints for Kerbals, though.. :-) DU would have never seen the inside of a reactor (it's a byproduct of enrichment), but could be used in a breeder reactor as feedstock to produce plutonium, or anywhere you need something dense to use for for counterweights, ballast, armor, or even for radiation shielding.
  19. if there's a common thread, it's that mechjeb doesn't check to see if what you're asking it to do is actually possible before it starts trying to do it..
  20. So it was really too much fuel in the stage before the tug... you should be able to shrink that stage's tanks and leave the tug mostly fueled and make it to orbit. I suspect that what you saw is a bug/unintended behavior (ascent guidance shouldn't be pointing the nose below the horizon during a burn!), but it may only surface when there's little to no chance of reaching orbit ...
  21. Been there, done that, sounds very familiar. Most likely too sluggish/too much fuel. Nuclear engines have great ISP but poor thrust-to-weight ratio. You can circularize your orbit with them but if you run out of lower stages while you're still in the atmosphere go back to the VAB and increase your TWR and deltaV. Look at the total deltaV and the TWR of each stage in the VAB. If the lower stages have a TWR of 2 and up, and total booster deltaV around 4K, you should be in a very good place to circularize with the nuke engine. Look at mechjeb's orbit info window when in flight. If you see a small and decreasing "time to apogee" when your perigee is still in the atmosphere, you're probably not going to space today.
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