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.
Crazy that the design is basically unchanged since WW2.
Are we talking dildos or swim fins?
That looks like it would dig in very uncomfortably into the shin..
Has anyone tried them while surfing? They would be good for the blokes who kick madly while paddling for a wave.
Double down and go shinfins and foot fins. Out paddle everyone.
I used these a long time ago for swim training and tried to use them bodysurfing. They were great for swim training and really even out your kicking with a unique movement and didn't dig into the shins at all. In the surf they'd help get you in a bit but once going they were hopeless, as you'd expect.
I bought some shinfins there in the cupboard ...i found that farting gave me more forward projection ...anybody want em
I'll give them a go if you don't want them.
Where are you bgreen ..im on the mid north coast ..happy for ya to have em
Brisbane, though I get down Ballina way fairly often. I can send you postage. E-mail ne on [email protected]
As a keen bodysurfer, i appreciate this article quite a bit. A history of handplanes next?
Fascinating fun fin facts.
A deeper dive with fins evolved into designs with rails, channels, combined flex & fixed foil fins....
Have had a crack on a lid a couple times in shorey style waves - this article made me want to ride one more.
Good on you Swellnet for promoting a broader view of surfing culture.
you want to talk swim fins, do you? I never enter the water without a pair. either for kneeboarding or going for a swim. doesn't matter what the conditions are you can always get out the back and back in, and deal with the strongest rips when you've got a pair of fins on.
ok, so yeah, churchills are the classic. asymetrical, quite heavy. not the right fit for me. feel too heavy on the back of the kneeboard. but everybody should own at least one pair.
da fin...these were the fin du jour of a couple of years back. now used by Hawaiian lifesavers. symmetrical with a big blade. they have a closed foot well. sand and grit get caught in there, so you have to take them off and empty them once you get out the back and after every time you touch the bottom. they come in some great colour combos. but I worry my blue and yummy-yellow pair might attract sharks. they also feel too heavy on the back of the kneeboard.
PODS -- Australian company. these are my favourite fins. really good fit. they come in three styles the PF1, symmetrical -- their shortest blade. great for bodysurfing. PF2 -- symmetrical , a bit bigger than the 1s. these are my favourite, go to fins. and the pod PF3 -- asymmetrical, their biggest, stiffest blade. pretty good.
duck fins -- symmetrical, long and skinny blade. too much blade for me. too much flap, bend and lost energy.
people often go for a fin with the biggest blade. but I feel this is the wrong approach. big blades weigh more take more effort (you will get really sore muscles) and longer time to move back and forth (in surf you want to make very quick strokes) and bend and flap to much, thus losing energy. I reckon the pod twos are the perfect combo of length, weight and thrust.
anyway, it's bit flat today, so off to Nowra to buy some more fns...
Thanks chook, some great info. In my limited experience I've found all the various designs for drainage still completely fail to remove the majority of sand and grit. I've got some DaFin ones now for bodybashing and the symmetrical design feels better on the knees, softer pocket is nice too.
Hadn't thought of Da Fins closed foot well. It would appear to be a flaw, yet DF have been my go to fins for a number of years, and I mostly use them at a gritty beach, yet haven't had an issue with particles getting caught inside - not more than any other fin anyway.
Yer lots of rabbit holes to go down. I thought it pertinent for this article to just follow the churchies lineage. What do you think about V1 vipers?
Finding perfect fin is a very personal thing.
Everyone has different feet, leg strength vs leg length , kicking style etc.
I love my duck feet yet find da fins and some other fins which others rave about to be way underpowered for me.
Best advice is to try lots of different lengths and shapes and see what works best for you.
Finding the perfect fitting/performing swim fin for me has been a never ending battle between comfort and performance. Over the last 2 years with all the swell we have been having I have been constantly nursing seal ulcers! A soft foot pocket and another width so the sides of your feet don't rub is essential if you are bodyboarding for hours every week.
I use 2mm neoprene booties and silicon toe caps.
Bought my first pair of Churchills in, the green ones, as a kneelo in the mid 70s. They came with a sticker of a green duck wearing a pair. The softness of the foot pocket was a joy after the hard blue ones I had worn until then.
I got into standing on my kneeboard in them on ordinary days. When I did I couldn't resist the urge to say "quack quack" as I rode along.
I started riding stand all of the time so ditched the Churchills but now often use the kneelo take off to get deep or make late drops as I become more decrepit and slower - pop up on the first top turn all going well.
Interestingly, the modern swimfin, (and yes, this includes most of the Malaysian mould popouts) has slavishly followed a design fallacy that prioritises a stiffer blade and softer foot pocket. The idea is that the stiff blade provides the power and the softer foot pocket provides the comfort. This is, in fact, total horseshit. The stiffer blade requires more effort to move against the water, and offers less recoil through the tip(which translates as propulsion) The softer pocket merely loads all of this up on the ankle, causing fatigue and calf cramps.
Think the fins of fish, the wings and feathers of birds, even any vaguely responsive surfboard fin. The flex tapers toward the end, not the other way round. If you have an hour and want to see a genius rant, ask Greenough about his thoughts on the modern swimfin. Its actually gone backwards in design functionality in the past 25 years.
When I ask the guys who make 'em why, they simply say its what the market wants, all based on a couple of simple, but erroneous, assumptions. It's the functional equivalent of taking the template of the modern surfboard but giving it the flex of a pool noodle.
The best current design is the Kpaloa fin out of Brazil IMO, but no one has got all the elements right
After near 30years bodyboarding Mike stewart MS vipers in the softer orange have all the elements correct for me. toobz fin are also soft tip
some good pints there, stormy. I think that explains why I don't like the bigger bladed fins -- they just amplify the problems you mention. whereas the pods are shorter and softer blade.
I'll see if i can get a pair of the Kpaloas in oz.
I had pod 3's, a lot of thought went into them from Shane, but I found them a little heavy. Shaved the ridges down the edges right back(about 10-12mm) and weight and flex improved dramatically
Churchill style fins actually work better if worn upside down&back to front,they provide more thrust & don't tire your foot out as quickly. Not sure of any hydrodynamic disadvantage but on a 42 inch square piece of sponge, who would notice?
Have been wearing Duckfeet for years for the air mattress.
Have found them more comfortable than most.
Agree with stormyandbo 100%...that flex is essential.
Vipers yellow dot 7 I found to be too big and boxy and bloody heavy. Would try the softer version if I could find a pair. Pink dot?
I never got on with Da Fins. The wide blade caused issues for me, touching at the tip on occasions. Body surf mates swear by them.
Have a pair of UDT's. Wore 'em once, nearly broke my ankles. Might trim those down Greenough style and see how they go.
I always wear socks 1.5-2mm.
Keen to try DMC and Yuccas.
Anyone had any experience?
Yuccas look quite good, not a fan of the DMC's at all. duck feet(and assuming udt's)work really well with the blade trimmed back shorter, to match the surface-level kickstroke.
DMC's too soft stormy?
Yuccas last time I checked, were something like $350-400 landed in Oz with the $ and shipping, hence I sat back.
Bought DMC Elite Max recently and they have this flexible, spreading fin edges that flare out on the down kick. Propulsion is fair but not off the mark speed that I require mainly due to the fin being too flexible length wise. The flexibility allows for longer water time because of less water resistance on the down stroke. The toe relief/drainage needs to be on top of the foot mould for more comfort. These fins are excellent for ocean and pool swim training. Need that rigidity length wise for surfing though.
Yucca's are epic mate. hard to get here. We did a large order from the US and had them shipped (30-40 pairs) and got a great price from him. I like the supersoft ones but the stiffer versions also great. You can get wetsuit material to pad the pocket and line the heel strap which prevents most rub. DO NOTE the sizing is different from most other brands so trying some on before buying is ideal.
Got any left Womble?
Sorry mate. They were all ordered specifically for individuals. I can ask if anyone wants to sell a pair on - some found the fit a bit iffy? What size do you wear in Dafin and that will help.
Can't remember my DaFin size, gave em away, didn't like them at all. I'm Gunna say xl as that's what I wear in duck feet. Just ordered some Kpaloas in xl. I always wear at least 1.5mm socks
Pretty sure I was looking at xl in Yuccas as well when I first touched base with them. I'd definitely be in if you can source a pair.
Max Dodshon using his body profile and fin as an edge.
He's got this nailed at the local. Also how's his outside leg.
Sick. Great control and way of holding to the wave face rather than going too fast/straight for a lip to the head or air dropping to oblivion on steeper waves.
All that wave energy so close, what a rush. "air dropping to oblivion" ahhh, :).
Yer that's what's known as " scooping" in boogin' lingo.
Jebus, that'd be tearin' me a new one...or tearin' something.
Great write up. Such a shame that the new churchies suck so much, nothing has come close since they changed the rubber.
I've always thought the Churchill/dolphin tale analogy is a nice marketing image with not much merit when it comes to propulsion. Who kicks like a dolphin? not many, if any.
But I've never thought too much about their function on a wave, until now. Can see how the longer "rail" on the outside of the Churchill could make them the fin of choice.
I wonder if a twisted symmetrical design would allow the long rail on the outside and keep the inside above the water when your on a wave, but also be better for kicking on the way back out.
Thanks for article and photo, well illustrated.
we kick with one leg at a time, so asymmetrical fin makes no sense, not half a dolphin tail. Asymmetrical fins have always twisted my leg and given me sore knees, I use symmetrical mike stewart vipers
What a great article, thanks, Dan.
We all learn a bit from history and I didn't know about Benny Franklin (well put, too, Dan).
The Bodyboarder & Bodysurfer have very different needs, so it's horses for courses. I do think the Churchill's are good on the foam, but not so much without it. I'm a fan of Da Fin's. They work well and if they're good enough for Mark Cunningham, they're good enough for me.
Scott Dillion told me he had a lot to do with designing DA Fins
Fantastic article Dan, great bit of history and design evolution.
Do a bit of body surfing myself. Used Churchills for years, but the foot cramps were killer and ended many a session. A couple of kneelo's, Big Pete and Terry Day got me into a pair of DMC Fins. Best thing ever. They look nothing like a fish or dolphin anatomy, more like the wings of a 1963 Valiant. But the fit, comfort and propulsion i find superior.
I bought recently the DMC Elite Max with the flexi edges and they need more rigidity down the middle for mine as they yield too much on the fin stroke. Toe relief/drainage needs to be on the top of the foot mould too.
Got a kick out of the Ben Frano reference.
The PS2 Hydros are my fin of choice with the highly flexible silicon rather than the harder rubber of the Duck Feet or Churchill's.
Not all feet are the same shape so fixed foot moulds are problematic. Big toe jamb has been overcome by some fin brands. Hard to find a combination of (enough) fin rigidity, lightness, off the mark propulsion and robustness.
Waiting on some Kpaloa Tritons, hopefully end of week. Shipping from Oz I think.
The annoying thing I found was that almost every other fin website shows the dimensions of their models.
Couldn't find a single measurement on the Kpaloas.
Some history about Churchills...
After World War II, Owen Churchill and my father approached Willard Voit and secured a 10-year contract to mass produce Churchill Swim Fins and other aquatic products. That agreement had an obvious impact on the popularity of recreational swimming (bodysurfing) and free diving.
Up until that time, all of the fins Owen produced had been black. My father developed a formula that would enable adding color to cured natural gum rubber without increasing its density. That's how Churchill Swim Fins became their signature green color and could still float.
While Owen and my father had become great friends, by the end of the term of the Voit contract, their relationship with Willard Voit had deteriorated to the point that they both opted to not renew it. Owen took possession of the Swim Fin moulds and my father went into another business.
A few years later, as my older brother and I became beach lifeguards in Los Angeles, we convinced our father to get the moulds from Owen, build a couple of presses, and start making the fins again on a smaller scale so we could make them available to our fellow lifeguards. We kept this small enterprise going, even after our father had died in a plane crash in 1966. We made the fins ourselves and sold them for $6 a pair, mostly to other lifeguards.
In 1973, our younger brother, Martin, decided to turn it into a real business, expanding production and actively marketing the fins to retailers for the first time since 1956. During that time, it was Martin who came up with the blue & gold Makapu fins and "Stiff Blade" Churchills.
Over the next 6 years, the business blossomed, with retailers from around the world ordering fins. This attracted the interest of Kransco, which owned Morey Boogie and Hobie at the time. In 1978, the family agreed to Kransco's acquisition offer.
Since that time, the formula for the material used in manufacturing the fins has changed. I still have my green pair, as well as a pair of 3-color Churchills our father produced for the International Free Diving Championships in Mexico in 1952.
Brilliant, thanks for sharing.
Great background, John
I agree that swim fins are really an individual choice. I've tried lots of different types and still prefer the Churchill blue and yellow style, but the latest ones are a weird fit. I tried 3 different ML pairs (the same size I've worn for years) and could only get one pair onto my feet. They soften over time, but it's a real effort in the early days. An advantage of symmetrical fins is that you can travel with 3, one as a spare, instead of having to carry 2 pairs. Kpaloa and Yucca are fins I haven't tried but sound interesting. I once had to try dive fins when I lost my fins on a surf trip - they were fun. I wouldn't mind trying a pair again. No one has mentioned Pride fins. If you like a Churchill style fin, they are not too bad.