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Need Aerobatic Expertise

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grassroots

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I have an acro/aerodynamics question that I'm having trouble sorting out in my feeble brain regarding right rudder outside snaps in my S-1S. If I do one and apply (left) recovery rudder in time, I can stop it on 1 rotation, and it seems like a fairly normal snap even though the ones I'm doing are fairly slow and not nearly as good as my inside snaps. But after one rotation, this "snap" basically turns into an end-over-end tumble. It makes little difference whether I use opposite rudder in a recovery attempt, or just hold the original right snap rudder and let it go.

This video shows three snaps. First one is the "normal" 1 rotation outside snap. The second one shows an attempt at stopping the snap after 1 rotation with left rudder. Tumbles. The third one maintains the original right snap rudder, just to let it go. Similar tumble. Entry speeds 110 mph. I shot this from the strut in an attempt to show the inputs I'm making. As the snaps break, I'm applying some (typical) left aileron and holding it.

I'm having trouble understanding how the dynamics of a right rudder outside snap (in this airplane) are so different from a left rudder inside snap. The inside snaps are very predictable, and my plane flies out of a left rudder inside snap between 1.5 and 2 rotations. I feel like my outside snap inputs with all three controls are pretty much the same as my inside snap inputs.

You can see the airplane goes forward end-over-end with slight aft stick held. Curious if anyone can explain what's happening and what I may need to do differently. The airplane is literally out of control until it gets enough downward trajectory to recover. I need to go work on left rudder outside snaps to compare. The first time this happened doing an outside snap was the first time I'd ever lost control of an airplane while doing aerobatics. I don't like it when that happens...but maybe I should just call it a deliberate airshow maneuver. :)

[ame="http://www.youtube.com/watch?v=DTbzx63itqc"]http://www.youtube.com/watch?v=DTbzx63itqc[/ame]
 

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