Thanks glisglis.
And yes glisglis is correct. The thicker part is the leading edge, just like a plane wing. And the other leg of it is the opposite way, basically just like a bent propeller.
And yep, the airfoil can vary. On the pvc ones I couldn't get the wing profile, so they just have a slight radius on the top and I added twist to them in opposite directions, not much, but just enough to give a little lift.
When I'm working on one I just end up throwing it a bunch, see how it's flying, scrape a little here or there to get the profile a bit different, throw again... over and over until it almost hovers off the ground as it goes.
As for throwing, yep thats how I hold it, but they are thrown horizontal to the ground if you want them to go straight. You can also throw at slight angles from horizontal and get a little bend to the flight, or even an s shaped trajectory, but that's more for fun than it is useful as a hunting tool
Here's my rough diagram. I hold this one where the arrow is, rotation direction shown, and the lines are the thick parts of the airfoil.
Hope this helps, they are quite rewarding when you get them to fly correctly.
