Mas tubercles

9" True Ames wide base.

Tubercle fin # 3

Board: Liddle 6'3" "Musgo"

http://www.otherpower.com/images/scimages/2637/leading_edge_tubercles.pdf

Fluid—whether liquid or gaseous—passing over a wing creates lift. But what distinguishes the humpback’s flipper from an ordinary wing is the presence of tubercles, or bumps, on the flipper’s leading edge. The tubercles enable the flipper to create lift at angles as steep as roughly seventeen degrees, because the water gets accelerated into an organized, rotating flow behind the troughs formed by the tubercles. A flipper with a smooth leading edge would stall, or cease to provide lift, at such an angle, because the water would be spun into a disorganized series of eddies.

It's kinda like 4 wheel steering.

LoVe