Chairborneranger Posted March 7, 2012 Share Posted March 7, 2012 In the process of getting my mun ships to rendezvous more reliably I\'ve been doing some fine tuning. I found that I was actually lugging more fuel than I needed on my second stages, so I decided to replace the half-tanks at the top with some RCS tanks, and add outward RCS thrusters for better mobility. During testing, and about halfway through atmo, I kinda fudged my accent vector and had to correct with RCS. After this I started noticing a large amount of natural yaw while at full engine throttle. With SCS and RCS on to correct, I finally hit apogee but by this time my yaw problem was outside my craft\'s flight envelope.After scrubbing the mission, it dawned on me that the RCS tanks must not be draining in a uniform manner. The exact same design with LFE tanks instead of RCS tanks doesn\'t manifest this instability. I know I\'ve seen someone on a youtube video (orbital garbage collector I think) have the tanks drain at the same time. Is this possible stock, or is it a game file tweak? S:| Link to comment Share on other sites More sharing options...
Ydoow Posted March 7, 2012 Share Posted March 7, 2012 More than likely, you experienced a bug. But it\'s not with the RCS.This happens to me 9/10 flights. Hypocee suggested/told me it was that KSP is saving/loading the thrust vectors incorrectly from the VAB.This causes your ship to yaw or pitch in some direction at any time you are thrusting.It\'s incredibly frustrating.I used to be able to get around it by going back to Space Center and redoing it, but now I have to restart all of KSP to eliminate it.It basically happens anytime I cancel a mission and start over. The first flight is fine, but any second or third attempts have the same issue you just experienced. Link to comment Share on other sites More sharing options...
AlexanderB Posted March 7, 2012 Share Posted March 7, 2012 If you built the tanks with the symetry option it should drain symetrically too.. if not, bug.. Link to comment Share on other sites More sharing options...
Kryten Posted March 7, 2012 Share Posted March 7, 2012 Are you using 0.14, or the free version? Link to comment Share on other sites More sharing options...
Chairborneranger Posted March 8, 2012 Author Share Posted March 8, 2012 I\'m using 0.14 and it\'s quite reproducible under all circumstances. The ship is rock solid at launch but the yaw grows as RCS is drained from the second stage tanks. It could be that because I didn\'t use symmetry to build the outer stages, that it won\'t place the RCS tanks using that.Guess I\'m going to have to do a complete overhaul of the second stage to truly test this. Thanks for the replies. Link to comment Share on other sites More sharing options...
AlexanderB Posted March 8, 2012 Share Posted March 8, 2012 It could be that because I didn\'t use symmetry to build the outer stages, that it won\'t place the RCS tanks using that. Link to comment Share on other sites More sharing options...
sjwt Posted April 10, 2012 Share Posted April 10, 2012 I don\'t think its the RCS, its the length of the ship, as the normal fuel drains your ships centre of gravy moves, you can either throttle down which helps reduce the leverage effect, or try re building out with multiple circles of radial decouplers, and dropping the empty tanks, leaving you with a ship that\'s no where near as tall.I am working on a Super heavy lifter at the moment, and its a real pain the try and balance it as it empties, to the point it goes from flying within 360-1 degrees almost dead straight then all of a sudden the centre of gravy moves, the thrust is too much and the ship starts to flip. Link to comment Share on other sites More sharing options...
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