sorry, the shocky f3a in the pic isnt mine. That one belongs to Devin McGrath. I dont believe he added the fins for side force generators...he uses tons of monofiliment string to stiffen his planes, and I think the fins are there to triangulate stings to the wing tips. His plane does knife egde very slowly, but I think it as more to do with the fact that it is 5.5 oz ready to fly.