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    Purple Pony in Space

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  1. Heya, I've playing with submarines lately (using the fantastic Otter mod by RoverDude), and I found that if I approach the submarine with another vessel and get into the loading range (2.2 km), I get the "vessel is destroyed" message and the submarine is no more. I tested this while having the submarine both at the bottom of the sea and on the surface, and the result is always the same. Is there something I might be doing wrong, or some clever way to prevent this? I am playing on 1.7.3. Thanks!
  2. Thank you for the quick reply! It's weird because some of the parts on my vessel should withstand temperatures over 3000 K, and they too exploded after a rather short while. I am using an older version of the game (1.7.3) and the respective version of your mod, and I am not sure if there have been any changes in this particular regard... or perhaps the additional heating is caused by light from Grannus. Either way, I am unable to find a way around it. Shame. I was so attracted by the notion of visiting the burning shores.
  3. Thank you for this wonderful mod. I have had it installed for a while, but only now have I progressed my career enough to start dipping my toes into it, and I am loving it. I have a question regarding Taranis, the warmest planet in the game. I have performed some test landings near the lava sea using cheats to see if my ship could withstand the extreme heat, and it seems like there is a script that periodically increases the temperature of the parts on the active vessel. I am still not sure as this is not exactly easy to test, but the heating seems to be directly dependent on the altitude above the sea level. Is that the case? I don't want to be delving into a huge, several hundred years long mission only to have my vessel destroyed by a script I don't understand. Thank you!
  4. This is my personal opinion based on several hours I spent testing FAR and I am open to objections. I think FAR is far from an "absolutely accurate" aerodynamic model. It does some things better than the stock game, but in other aspects it is actually worse. And here is what i mean by this. 1) Cambering. FAR takes zero account for cambering (the shape of the cross section of the wing), which means that unless you have a positive angle of attack or a positive incidence, your wings produce zero lift. This is unrealistic and the stock game does this actually better, producing lift even if your craft moves in a parallel direction to the plane of your wing surfaces. 2) Ground effect. In reality, the lift coefficient of your lifting surfaces is somewhat higher when you are close above the ground, which does actually help noticeably during take offs and landings by decreasing the stall speed. FAR, as far as I can tell from the tests I did with it, does not take ground effect into account. 3) Take off and landing speed. In reality, a typical airliner is capable of taking off and landing at speed somewhere between 70 m/s and 120 m/s. In FAR, I haven't managed to get into the air at speeds lower than 200 m/s. I performed an exhausting number of test flights - with my crafts, with stock crafts and even with the crafts that came with FAR, and with the exception of the FAR included fighter jet (I cannot recall its name), it was impossible to maintain altitude at speeds below cca 200 m/s, which makes a safe landing of your average SSTO pretty much impossible. The only reason why the FAR fighter jet had a better performance than the other aircraft was because it was equipped with an unrealistic amount of control surfaces. This is not how real aircraft should behave IMHO. 4) In flight stability. Again, all the aircraft I tested, including stock and FAR aircraft, displayed a severe and immersion breaking instability in pitch and yaw directions even close to trans-sonic speeds. Real aircraft do not wobble up and down, FAR aircraft did for me. Perhaps I was doing something wrong, but all the SAS on/off and FAR stability autopilot on/off combinations have been tried with zero effect. 5) Aerodynamic shadow. In reality, if you put the tail wings close to the main wings, the tail wings will be robbed of the stable airflow they need by the wings in front of them and will not function properly, if at all. None of this is to my knowledge simulated by the FAR model. Having said all this, I think your best bet is to install FAR, play with it for a couple of hours, try different types of aircraft, watch their behaviour closely, and then decide whether you prefer the stock model or the FAR one. Neither of them is perfectly realistic, so do not believe people who say otherwise.
  5. For SSTOs perhaps. Otherwise you just drop the extra weight of the engines and their respective tanks. Boosters never make any craft less efficient since you just leave them behind. It's true I didn't specifically mention aerodynamic heating. Isn't aerodynamic heating part of the aerodynamics? I imagine the heat transfer must be lower for crafts with smaller cross-section area.
  6. That really depends on the range of mass / thrust / engine efficiency and drag coefficient within which you were performing the tests. I haven't tested this myself and I'll be happy to take your word for it. However, if aerodynamic drag was not significant, everybody would go straight for insane TWR and tilt their rockets directly to the east right after lift off, which is not something I have ever seen from any experienced players. Besides, I have recently launched a large rover attached to a sky crane, which means I wasn't able to put it inside a fairing, and I can tell you, even though the starting TWR was below 1.5, I soon found myself throttling down just to avoid the thing breaking apart, not to mention the drag force losses. So, in some instances, the drag does play a noticeable role. EDIT: After reading through my earlier post and your reaction again, I realised there has been a poorly worded claim on my part. What I meant by 'aerodynamics being the main factor' was that aerodynamics is the main factor in favour of the steep climb. The other factor being gravity only favours flat, horizontal ascents. In other words, if you are deciding how steeply you should climb, the "dragginess" of your craft is the main thing you should be concerned with. I hope we understand each other now.
  7. Good question. In an environment devoid of atmosphere, the highest possible TWR would be the best for the reasons mentioned in the original post. Once you are launching from an atmospheric body, the main factor is aerodynamics. If you're launching a large rover and you didn't bother to put it in an aerodynamic fairing, you want to go as slow as possible through the atmosphere and a TWR of 1.2 - 1.4 will be optimal. If on the other hand you are obsessed with aerodynamic shapes like me, to the point of putting solar panels and antennas into cargo bays, you might wanna aim for a TWR of 2 and more. What I am trying to say is that what you are asking is dependent on too many variables: gravity, atmosphere density and its height, not to mention the rate of change of pressure and density with altitude; then you need to take into consideration the efficiency of your engines (with engines of incredible efficiency it would be probably best to get through the whole ascent in subsonic speeds to keep the drag at its minimum), weight of your craft, staging and last but not least the drag coefficient of your craft. I imagine there must be some insane calculations going into planning of the flight path of real world space crafts, and even then I would be not surprised if they only aimed for 'good enough' instead of 'optimal'. And that would be my advice to you. Try a few ways of launching your vehicle and stick to whatever is 'good enough'.
  8. This can be actually done in the Cartesian coordinates. The function for the upper half of the ellipse (we can only take one half since it's symmetrical) is: y = b * sqrt( 1 - x2/a2 ). Integrating it over dx requires a clever trick of substituting x for for a new variable z with this condition: x = a * cos(z). You get this formula for the surface area under the ellipse curve: S = a * b * integral( sin(z)2 * dz ) This can be tackled easily with the knowledge of the trigonometric equality cos(2z) = cos(z)2 - sin(z)2, which gives you sin(z)2 = ( 1 - cos(2z) ) / 2 Your integral is then S = a * b * integral( (1 - cos(2z)) / 2 ) dz, which then can be torn apart into two integrals, both for x running from -a to a (after having reversed the substitution). You end up with a formula for the surface area of an ellipse (a whole ellipse would yield pi * a * b, by the way). Then you simply subtract the surface area of the yellow triangle below the line segment dividing the green and the yellow areas and you get a nice formula for the green surface area (the upper half of it rather). Then you have to solve what you got for T, where T is the x coordinate of the dividing point which we are really trying to find. I did a very similar calculation with my high school students and many of them got the gist of it, although admittedly none were too keen to be tested on this. EDIT: A big shout out to the administrators of the forum. Why do we not have an equation editor?
  9. The mathematical solutions satisfying the given time requirement does actually involve orbits that barely dip above and below a chosen mean altitude.
  10. Can anybody explain to me what is so appealing about having KSP on a smart phone? I play it on a laptop with a 17 inch screen and all the GUIs from both stock game and mods like Engineer Redux or Scansat cram my screen so much that I had to increase my resolution to fit it all in and now I have to actually wear glasses while playing the game just to be able to read it. Why would anyone want to fit the game on a tiny screen of a phone? How do you expect to see anything let alone control it?
  11. Hello @Hoonter and welcome. It pleases me to see that new people are still delving into the world of KSP. A little tip / trick from me, which has worked for me marvelously in all stages of the game, is to put some radial decouplers under the wings or the hull, set the decouplers to "Enable Crossfeed" and onto them attach a few fuel tanks. Of course, make sure the plane can carry the extra weight (they usually can, KSP engines are powerful enough), and also be careful to place the tanks in such a way that they do not mess up your balance. It is generally advisable to place them where your centre of mass is. Then, if you manage to take off, the fuel will be first draining from the external tanks while leaving the fuel in your plane's hull untouched. Make sure you monitor the amount of fuel in the external tanks, and once they go empty, drop them. This procedure can double or even triple the range of any flying machine.
  12. This is an interesting mathematical problem. Not impossible, I reckon, but the difference between your periapsis and the mean altitude would have to be larger than the difference between the mean altitude and your apoapsis, since objects always travel faster the lower in the gravitational well they get. In mathematical terms: |M - P| > |A - M| where M is the "dividing" altitude (60 km in your example), A and P are Apoapsis and Periapsis respectively. Not sure how serious you are about the answer, but I could imagine the simplest way to calculate this using the Kepler's laws. The second Kepler's law tells you that the ratio of time spent on any two segments of an elliptical orbit is exactly the same as the surface area covered by a line segment between your vessel and the centre of the celestial body you're orbiting. The request of t1 = t2 thus translates into S1 = S2. Now all you have to do is pick an eccentricity of an ellipse, write down its analytical equation and integrate it to get the surface area. EDIT: And by altitude in the picture above I mean altitude above the centre of the body, not its surface. It tends to be easier to just forget about the size of the celestial body and simply view it as a point. You can always subtract its radius from your result.
  13. Hello there. I've noticed that the Grannus Expansion Pack (an absolutely beautiful mod, by the way) developed by OhioBob uses names of the Celtic gods to name his planets and moons. I personally find this to be a great idea, so if you struggle with naming your celestial bodies, you might want to search the wiki for some polytheistic pantheons. To give you some idea: Sumerian gods (Shamash, Inanna, Enlil, Enki,...) Egyptian gods (Ra, Osiris, Horus,...) Slavic gods (Perun, Mokosh, Svarog,...) Nordic gods (Odin, Thor, Freyja,...) And many many more. There's a lot to chose from.
  14. I suppose this is as much a plead to the modders as it is a question whether there is such a mod already. It would immensely improve the quality of life to be able to filter the offered contracts by a celestial body. For example I am planning a big mission to Eve and thus I am potentially interested in all the contracts that have anything to do with Eve. It might not be of a particular issue in a stock game where the number of offered contracts and the number of planets and moons are limited, but I play quite a heavily modded game and going through 30 contracts to see if there is anything relevant to the planned mission every time I launch one is a genuine nuisance. Does anyone know of anything such?
  15. Issue resolved. For anyone who might be as dumb as I am - there was another config file which further adjusted the properties of the part in question and it interfered with the main config file.
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