Hey, thanks, this is cool. I finally found a forum where people don't slam people for getting technical on aerodynamics.

I didn't know about that 3 degree angle. That's interesting and a little surprising. I never expected it to be 60 degrees or anything, in fact I suspected that the pictures I have seen in my studies exaggerated the density of the "coil" for illustration purposes but I didn't know how much.Still, it's effect is very observable in flight if you understand the principles.