I would have used a 13x6 on that saito but the only difference would have been more rpms and better acceleration during take off. What I dont understand is why you kept the engine at 1/2 throttle on take off? Initial climb out needs all the power you could give it and normally as you accelerate down the runway you should be already at full throttle before you pull back on the stick. Seems to me that one wing dipped and the airplane was at the merge of a stall when you added aileron so it aggravated the situation and without enough power to fight the amount of drag it dropped a wing. Sorry for the crash, looked like a gorgeous bird. []