#892: HingeFins

Today’s invention offers a way to increase swimming speed for eg lifeguards.

Instead of the usual webbed palm paddles, the idea is for the swimmer to wear a neoprene sleeve on each forearm. A hinge (lightly-sprung closed and with a backstop to limit opening) connects each of these to a semicylindrical plastic blade.

On reaching forward, the semicylinder’s end slices through the water and drag force is very small. As the power stroke initiates, it opens the blade from the sleeve, catching a large scoop of water and provides enhanced thrust.

As the arm retreats through the water and up into the air, the blade is forced back flush with the forearm and the process repeats.