There is a better way :
Google search inflatable SUP boards construction ; and you get something
like this :
http://www.supnorth.co/why-red-paddle-co/
Self explanatory, as to how this technology could be used !!
We'd be using about as much of the airfoil on the LE , as where
the #2 is located on the cross-section or maybe a bit more back to
almost #3.
I tried to draw a circle where the bladder is now, with my mouse LOL
and the blue line represents the portion of the airfoil i would use.
See how the airfoil is nice and flat on the bottom surface, (behind the circle)
i drew in ; i think a sharp angle L shape, where the air exits and goes rearward
toward the back of the kite, instead of the round tube we have now, would
create a LOT less drag on the bottom surface. Actually i Know it would be less
draggy, and the stagnant air behind the step, would act almost as good as a
full double-surfaced bottom we have now on our ram-airs.
Weight wise would be of little concern to me ; kite size for this technology would
probably be 12M or less, (not made for light winds) but built for winds of 20-kt +.
Bille