The Cut and Thrust of Swim Fins
In the tangled history of the swim fin there are a few contenders for the 'inventor' label.
Leonardo Di Vinci, in pursuing his investigation into the possibilities of flight, dabbled in the world of hydrodynamics leaving behind sketches resembling slightly altered bat wings extending off the hands and feet.
Benjamin Franklin was also an Enlightenment-era explorer in the aquatic propulsion and swim fin market. Reportedly an avid swimmer as a young bloke, little Benny was constantly on the lookout for ways to increase his swimming speed.
As an adult, Franklin wrote:
“When I was a boy I made two oval palettes, each about ten inches long and six broad, with a hole for the thumb in order to retain it fast in the palm of my hand. They much resembled a painter’s palette. I remember I swam faster by means of these palettes, but they fatigued my wrists. I also fitted to the soles of my feet to a kind of sandals; but I was not satisfied with them because I observed that the stroke is partly given by the inside of the feet and the ankles and not entirely with the soles of the feet”.
The development of the modern swim fin for oceanic use began at the beginning of last century with a French Naval Lieutenant Commander named Louis de Corlieu. Corlieu gave a demonstration of his prototype fins to a group of officers in 1914 before leaving the navy in 1924 to work on his invention, registering a patent on propulseurs de natation et de sauvetage ("swimming and rescue propulsion device") in 1933.
Around the same time, an American Olympic yacht racing gold medalist named Owen Churchill claimed to have gotten the idea for personal swim fin propulsion by, in 1932, observing Tahitian divers attaching woven palm leaves or strips of soft rubber shaped like fish tails to their feet and set about developing his own prototypes of this idea.
In 1939, Churchill was granted the licence to manufacture the Louis de Corlieu’s propulseurs in the United States. He changed the name to swim fins, improved the design and secured a contract to supply American and English commando frogmen with his Churchill Swim Fins during World War Two.
After WW2 ended and the Cold War commenced, legend tells that a Russian operative in the US got his hands on a pair of the US manufactured Churchill fins, but couldn’t find a way to smuggle them to the USSR. He was, however, able to describe the design well enough that the Russians could begin production on their own version of the Churchill design.
The Communist-manufactured 'Model 1' swim fin was made in the Mosrezina plant, which was a portmanteau of Moscow and the Russian word for rubber - rezina. Like the Churchills manufactured during WW2, they were green in colour, however being made of foam rubber they didn’t sink when lost, making them potentially the world’s first floating fins.
In the intervening years post-war years, Churchill swim fins became popular with lifeguards in the US and Hawaii and soon became the fin of choice for many early bodysurfing pioneers. With the birth of the bodyboard in 1971, swim fins found a whole new set of disciples.
From a design perspective the curvature of the inside blade on a Churchill style swim fin bears a remarkable similarity to the curvature on a surfboard fin. George Greenough famously drew on the shape of tuna fins for his early surfboard fins, while Churchill claimed inspiration from the tail of the dolphin.
(An inverse pair of Churchill fins were also used to create the curve and shape of the original Steve Lis fish tails)
As any bodysurfer or bodyboarder worth their salt will tell you, this synergy of design has practical applications in terms of control and performance when wave riding. Swim fins serve not only as a means of propulsion and getting on to waves for the prone posse, but also play a significant role in allowing control and positioning once actually on the wave.
While a bodyboard is only on average 3’5" long (42 inches), when the leg and flipper-covered foot of the rider is included, that extends that out to around six feet, roughly the same length as a standard modern shortboard. The often unacknowledged key to riding a bodyboard well is the fact that the lower limbs essentially function as highly manipulative extensions of the board's rail line.
The basics are pretty simple. Lifting the leg clear of the water will reduce drag and increase speed, dropping the leg or knees into the wave face slows you down and gives the rider more control.
However, managing and manipulating the variables of leg and foot drag and angle whilst also manipulating the flex in a bodyboard is a bit like managing the pitch, yawl, and roll when flying an aircraft. Depending on the pilot's level of experience and skill the actions can seem smooth and effortless, or jerky and clunky.
If you watch good bodyboarders closely you’ll see these subtle leg adjustments as they travel along a wave, particularly when close to the bowl.
The outside hard edge and tip of the swim fin is what anchors all of these movements and is as essential as a fin on the bottom of a surfboard for maintaining control and generating drive. Along with the back tail peg on the bodyboard itself, the outside edge and tip track into the wave face, providing a point of control and drive.
Swim fins, particularly the Churchill dolphin shaped design, have also taken on, for want of a better phrase, cultural significance within much of the bodyboarding scene. In much the same way that a plain black wetsuit and plain white board are standard issue for the majority of 'core' shortboard surfers, the Churchill-shaped swim fin has become associated with style and technical riding within the boogieverse.
Carrying on the influence from early pioneers like Mike Stewart and Ben Severson who used Churchill fins, Australian riders like Ben Player, Mitch Rawlins, Damian King, and most influentially Ryan Hardy made Churchill shaped fins synonymous with the style and look that bodyboarders have aspired to for much of the last thirty years.
Multiple companies within the bodyboarding industry now tie in this desire for a certain aesthetic by offering a variation of the Churchill-shaped swim fins for sale, usually just in different colour combinations.
This is largely thanks to what has become known within the industry as the 'Malaysian Mould'. Essentially anyone willing to pay can utilise an open mould located in a factory in Malaysia to create their own copy of the Churchill fin shape, just with a company's decal affixed to the top of the flipper. Interestingly, the factory's main product is rubber dildos.
So next time you see a booger or bodysurfer whacking on a pair of dolphin-shaped swim fins know that they carry a sprawling history that touches upon Enlightenment-era thinkers, a Tahitian swimmer, French Generals, American Olympians, World War 2 demolition teams, Communist knock offs, and a Malaysian sex toy.