#Baron_Surfboard project part 6: Foiling the tunnel fin and boomerang fin

Here's the new boomerang flex fin which wil be used in combination with the vort-x tunnel fin.This fin is a development of the previous bulb tipped flex fin used on the Baron prototype. The concept here is to use an extremely thin low chord ratio in the tail of the fin , so that the fin flexes like a fish. This will reduce lift in the tail of the fin but will provide an extremely low drag fin. The bulb tipped prototype fins were excellent but we're chasing even lower drag. The chord ratio on the fin tip is around 1.6% which is very low when the usual range for chord ratios is 9% to 14%The animation below shows the amount of deflection which the fin achieves with only moderate pressure.Foiling the tunnel fin