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    Sr. Spacecraft Engineer

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  1. Thank you, that is very interesting indeed. Could it be, that the ton of circular references that you mentioned, is making the software iterate a solution, and causing inconsistency in results? I do not remember ever seeing this reported, or discussed here, as an issue, but I can not help noticing, that the calculations are often quite inconsistent. For example sometimes moving or rotating some parts, and returning them to the exact same place, produces a noticeable change in stability.
  2. Thank you for your reply! Though, the wiki only talks about it from the end user perspective, while my questions are more about the maths, happening inside, to convert all these values into a flight model. Also that page talking about Blender, refers to the wing planform shape as an "airfoil", which is an entirely different thing. Airfoil normally means the cross section of a wing, or more broadly, its characteristics, such as lift drag and pitching moment as a function of the angle of attack. Similar to the static graphs the mod makes, but for a section of a wing. FAR, I suppose, is not computational fluid dynamics software? No way that is happening in real time, is there? Therefore it has to make some assumptions, and use empirical approximations, which is very difficult to do with an arbitrary shape, from the voxel model. That is why it is so interesting what it does. I am closely related to aerospace engineering in real life, and I have been thinking for some time now, about some of the things that the mod does, and how it can be improved further, to be a more accurate model of real physics. The problem is I know pretty much nothing about coding. So, if anyone, who understands the mod source code, could tell me in normal language, or even in equations form, what it does, I would greatly appreciate that, and possibly, be able to contribute to improving the aerodynamics.
  3. Hi guys! Does anyone know what aerodynamics model does FAR use? What parameters are assumed from the voxel model shape, and what information is taken from the wings config files? What kind of airfoil or lift curve shape does it assume for the parts it classes as "wings"? What about body lift? Thank you!
  4. Hi everyone! I am having a weird effect, where the Kerbal Engineer, the readout in the vanilla toolbar, the Mechjeb vessel info, and its stage stats, give out three different mass values, for the exact same vessel. I thought this was an old bug, fixed some time ago already. It is not related, to whether the parts are crewed or not though, so not sure, if that is it. Any ideas why that could be happening? Thank you!
  5. So, this is not a Mechjeb software bug, as such, but rather a realistic limitation of the actual algorithm? In other words, the guidance algorithm does not know, how to get to orbit from that set of starting conditions, and it will work, if brought closer to a working solution? Is that what you are saying?
  6. So, at the moment, does Mechjeb use the Atlas Centaur guidance, or the Space Shuttle guidance? Are both of them referred to as PEG? While I see how the Shuttle version should be more accurate, how is that related to how often it bugs out in game? As I said before, it does not seem to be related, to how complicated the task is, or whether it is possible at all. Sometimes, it works perfectly and sometimes refuses to produce the numbers, for the exact same vessel. I somehow doubt that happened a lot in real life, even in the early days Also, the early two axis guidance code, may be a good thing to leave in on purpose, at least as an option, for people, who in one way or another, play career mode, or roleplay historical progression. After all, real Sputnik missions were flown with guidance, much closer to the early Atlas, than to the Shuttle Anyway, why would it refuse to work like that? Maybe, there is a particular action, or pattern of actions, that make it happen somehow? I do not remember having this problem with the earlier versions. Would it help if I post the logs?
  7. Wait, what do you mean, normal releases have a non functional PEG? This week I had at least four PEG launches. I mean successful ones. And I am using a normal release. My problem is that it bugs out sometimes, but it certainly does not only function, but steer much better than me.
  8. Hi Everyone! I am having a rather strange problem with the Powered Explicit Guidance in Mechjeb ascent autopilot. Sometimes, seemingly randomly, the stage analysis window throws NaN, instead of some of the numbers for the stages. When that happens, A, B and pitch become NaN. The time to go reading is sometimes an erratically changing negative number or just another NaN as well. If I launch like this, the guidance mode will never engage, and the autopilot will just stick to prograde indefinitely, after the pitch program. It, usually, tends to happen after reverting a flight, but sometimes, immediately after starting the game, or even creating a completely new save. It does not seem to depend on the vessel or whether it is physically capable of reaching orbit. I should say that I am also running Real Solar System, and the basic mods from the Realism Overhaul pack, but everything seems to work, so not sure, if this could be contributing. What could be causing this? Thank you!
  9. Is it correct that if you disable the stock resource survey system the stock survey parts functionally also become SCANSat?
  10. Hi everyone! Now that all the essential mods, including RSS seem to be updated, what are the plans, regarding Realism overhaul? Looking forward and really can not play without it Thank you!
  11. The topic title is inconsistent with the new version released - it still has the old version number
  12. We are patiently looking forward to you getting the time for KSP Sure, real life always comes first though, good luck with solving all of your difficulties successfully!
  13. Hi everyone! I just discovered something I would like to ask about. I appreciate @blowfish taking my data into account and taking the steps to adjust the calculated idle thrust of the engines, but I am afraid it, somehow, did not have a significant effect. The numbers above suggest, that static idle thrust should be, from 3-4% of the full rated thrust, for high bypass turbofans, to 7-10% for turbojets without bypass. Currently the stock TF-34 turbofan, for example, develops as much as 7 kilonewtons of idle thrust, which is 17% of its rated 41kN. This appears to be almost the same as before, if I recall the previous test runs correctly. The CF-6 produces over 18 kilonewtons which is almost twice as much as it should do. The CF-6 variants are actually among the engine types that are shown in the Boeing documents. See the first of my three links on page 12. Also KSC seems to be an extremely hot place. As hot as 40 degrees C. That means that engines, of course, do not develop their full thrust, so on standard day, idle thrust is higher than that. I understand that this discussion is a bit dated, but I took a break from kerbal things for a while and just recently came back to building kerbal planes seriously. Maybe there is something overriding the default idle exit pressure value in the engine specific configs? Or some other setting affecting this? Also as most of jet engine nozzles are subsonic, should the pressure at the outlet actually be less than ambient and not more? Thank you!
  14. Any chance you can consider uploading what you have done so far since the last update? It seems like quite a lot of stuff and those teaser screenshots are mouthwatering beyond doubt
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