RE: Katana 50 by Hangar 9
Sorry you had to go through all of that, but it sounds to me like you were the victim of good old flutter.
You touched on mechanical advantage regarding the servo horn vs control horn, etc. I believe that is your problem, or else those JR servos aren't strong enough. I'm not familiar with the current JR/Spektrum line up, so I don't know.
My point here is, with those huge control surfaces this model has, if one reverses the mechanical advantage then that is pretty much a guarantor of flutter somewhere down the road. We know how destructive flutter is; sounds to me like you were lucky that the covering held the wing together long enough to get it down. There are few wing structures that could hold up unscathed to the severity of flutter that you described. And there is darn sure nothing wrong with the kit-supplied linkages. Good, stiff 2mm pushrods with excellent ball links and clevises.
Again, I am not directly criticizing what you did, or your observations... with one exception. I don't believe there is anything "badly designed" about this model. The designer has a bunch of successful designs to his credit, and this isn't the first one of those I've flown.
Anyway... hope it holds together for you; it is a superb-flying model when flown IMAC style. I cannot comment on its ability to flip-flop around, since I cannot fly that stuff.
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