NATURE’S PROPULSIVE V-SHAPE
If you’ve observed fast-swimming fish like tuna, mackerel, jack, pompano, marlin or dolphin fish, you’ve probably noticed that they all have tail fins — caudal fins — that
(1) are relatively small compared to the size of their bodies,
(2) are shaped like a crescent or in a “V,” and
(3) are tall or wide, but short.
These constantly swimming fish are models of efficiency, built for a hunting existence, ranging the ocean and able to swim for miles on end looking for food. By contrast, the slower-moving bass, grouper, rockfish, croaker and snapper that tend to be bottom feeders or grazers and are found skulking around reefs and caves have blunt or squared-off tails.
What is nature trying to tell us? First, fins don’t need to be long. Second, the best shape for a hydro-mechanically efficient tail that reduces resistance or drag is one that is V- or crescent-shaped and with a high aspect ratio (aspect ratio is the wingspan of the tail divided by its average width); that is, a wider but shorter tail like a bird or airplane wing or fish tail — or like the blade of a FORCE FIN.
“The curves and flexibility of the Force Fin stabilize your legs, keeping them properly oriented for a more efficient and powerful kick. The drag of other fins causes them to torque to an inefficient angle for generating propulsion, particularly as you tire after kicking a long distance or against a current.”
Have you ever seen a fast-swimming fish with a blunt or squared-off tail? Neither had we. That’s why we patterned our fins after the split-V shape of fish tails that more efficiently channel the water.
We also noticed that other fins worked basically like boards tied to your feet; they were stiff and inflexible. Again, we took our cue from nature and physics, and we came up with flexible fins using innovative materials like polyurethane, instead of hard plastics.
An efficient fin helps channel the water by having it flow off the ends and not the sides of the blade, putting more energy into forward propulsion.
With the FORCE FIN, we invented water channeling by looking at fish tails and forming the blade into a naturally efficient shape. In fact, what really sets our fins apart is the patented blade that curves up and away in a V-shape from the bottom of the foot.
Our snapping, curved-in wing tips help direct the water toward the ends of the fin, just like a bat ray’s wings do. On the recovery, they fold downward, increasing the vertical range of the water channel behind you. More water is moved but with less drag or resistance.