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Pirate Roberts

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  1. Does the RT-10 thrust change during the last 10 seconds or 10% of burn? Or is it consistent (or at least follow the same Atmospheric pressure to thrust curve)?
  2. Thanks, I already have sound barrier in my model it seems to cover the sound barrier on ascent and descent quite accurately, it wasnt that hard to model I just made a simple drag multiplier between 300 and 360 m/s. I think it might be temperature. I read on the wiki that atmospheric temperature doesnt have much effect on the game but I think it does something. Its maybe nothing to do with comming out of the sound barrier its that the vessel is entering the stratospheric temperature gradient around 12500m, I'm going to add atmo temp profile see if that helps.
  3. I'm trying to model atmospheric ballistic trajectories. I think I have a good approximation using excel (but not so much on the calculus). I modeled acceleration, thrust, weight, drag and have an approximation to drag through the sound barrier. I have assigned a drag coefficient that seems to work. My model works pretty good launch and through sound barrier. After SRB burnout I model a ballistic trajectory to descent back through the sound barrier as far as chutes out and my sim is over. Problem : Ascent Velocity from immediately past sound barrier > 360m/s to engine burnout and Ap isnt matching my model and is out buy about 5%. My model is faster than flight test comming out of sound barrier I've got TWR correct ie model matches KE readings. It took a bit but eventually I got a fudge for Thrust efficiency against atmospheric pressure with a decent stdev. I used a logistic curve to approximate the efficiency curve that KE reports in the VAB (yeah whatever but it works) I've modeled Kerbin Atmosphere and drag F_Drag=1/2.P.v^2.K where K is a drag coefficient I tweek till matches "reality" (well flight recording), I did flight recording by screenshotting every few seconds and entering the data back to excel. (maybe there is a quicker way but its ok). I know its not that I got the sound barrier approximation wrong from 300-360m/s because my model matches recording all the way to 360m/s then starts diverging. The brunt is : is there something happening with drag as you go supersonic (>360m/s) that I need to consider? Thanks ahead to any help, I would like to show the graphs but I'm not sure how to post pics, Im hoping there is something silly I forgot. PS I'm new to the game its my first and only career , never did sandbox have a ton of mods, killed three Kerballs and have started a science program that so I dont loose more greenies. I play very slow but I'm really loving getting back into basic physics its really wonderful. .
  4. Thanks HvP, I fixed it by deleting Kerbal Engineer \GameData\KerbalEngineer directory completely and reloading Kerbal Engineer in Ckan. Its back to normal though KE is back to default settings which is ok at this point. I had backed up KE dir before I deleted it, I checked the files you mentioned but the line you mentioned was correct. (see below). Once I fixed it I tried to reproduce error and couldnt. Anyway thanks for your help, I can get back to my SRB drag estimates. <?xml version="1.0" encoding="utf-8"?> <ArrayOfSettingItem xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <SettingItem> <Name>multiplier</Name> <Value xsi:type="xsd:double">1.1</Value> </SettingItem> <SettingItem> <Name>increment</Name> <Value xsi:type="xsd:int">0</Value> </SettingItem> </ArrayOfSettingItem>
  5. I'm using Kerbal Engineer Redux 1.1.7.1. Been using it a while no problems, today I somehow managed to minimize the Engineer data pane in the VAB to a very small grey box with no buttons visible and I cant resize it. The icon on the bottom of screen is still there but all it does is make the Kerbal engineer pane appear or dissappear. It looks like the pane has collapsed to a minimised version of itself but without an obvious way to expand it back to normal size. I think it minimized when I either clicked (in kerbal engineer top tabs) "settings" or maybe "compact", the minimized pane is now just a tiny gray box, I've tried clicking all over it, closing reopening , searching online. Thanks.
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