I have had more than one theory about these fusealges breaking, Mine are braced with the specified tail area fuse former and cross braced with balsa or compsoite material all of the way to that former.

Did that make mine immune? Probably not.

I think that the rudder and stab and much heavier that what we are used to. And all of that mass back there flicks around with fatiguing results. The "neck" or narrowest part is vulnerable to excess weight forces behind it.

My Impacts have 1.5 oz rudders and no servos in the stabs. The stabs themselves could be a lot lighter as well.

Just a "Theory".

Eric.