Dolphin-Inspired Man-Made Fin Works Swimmingly (swim twice as fast as Michael Phelps!)

Lunocet swimmers have already hit about eight miles
per hour, almost twice the speed of Michael Phelps
at his fastest

The human body does many things well, but swimming isn't one of them. We're embarrassingly inefficient in the water, able to convert just 3 or 4 percent of our energy into forward motion. (Even with swim fins, we're only 10 to 15 percent more efficient.) But a new, dolphin-inspired fin promises to fuel the biggest change in human-powered swimming in decades, putting beyond-Olympian speeds within reach of just about anyone.

Culminating decades of research, engineer and inventor Ted Ciamillo, an inventor and engineer in Athens, Ga., who made his name (and fortune) building high-performance bicycle brakes, created what he has dubbed the Lunocet, a 2.5-pound (1.1-kilogram) monofin made of carbon fiber and fiberglass that attaches to an aluminum foot plate at a precise 30-degree angle. With almost three times the surface area of conventional swim fins, the semiflexible Lunocet provides plenty of propulsion. The key to the 42-inch- (one-meter-) wide fin's speed: its shape and angle, both of which are modeled with scientific precision on a dolphin's tail.

These sprinters of the sea can swim up to 33 miles (53 kilometers) per hour and turn up to 80 percent of their energy into thrust.

"The mechanism functions like a wing to generate a lift force," which is directed forward and turned into thrust, says Frank Fish, a marine biologist at West Chester University of Pennsylvania. "This propulsive mechanism is extremely efficient compared to conventional rigid marine propellers." Fish, a specialist in the swimming morphology of marine mammals, provided Ciamillo with data from CAT scans of dolphins' tails that he used to design his fins, which went on the market last year for $1,800 each.

Lunocet users have already hit about eight miles (13 kilometers) per hour, nearly twice as fast as Olympic Gold Medal swimmer Michael Phelps at his speediest.

Using the Lunocet, some swimmers are close to being able to breach completely out of the water, like whales. Ciamillo envisions a new high-speed, free-diving community of swimmers united around "hydrotouring": long-distance swimming expeditions using Lunocets to cover dozens of miles a day, with participants carrying streamlined, waterproof packs containing only a global positioning system (GPS), satellite phone, and enough food and water for a few nights on shore.

The fin could also have a "profound effect" on the sport of free diving (where divers compete to see who can go the deepest while holding their breath), says Grant Graves, president of the U.S. Apnea Association, the country's leading competitive free diving organization. Its efficiency could let those who dive by holding their breath set depth records by going deeper more quickly. Still, speed isn't everything underwater. "The faster you go, the harder you have to work," since drag increases as the square of velocity, he says. "There's a sweet spot between friction, speed, oxygen consumption and distance."

Another attempt to balance that equation is taking shape in the labs of inventor and entrepreneur Dean Kamen's company, DEKA Research and Development Corp. in Manchester, N.H. The creators of the Segway two-wheel, one-person electric vehicle are working with the Defense Sciences Office of the U.S. military's Defense Advanced Research Projects Agency (DARPA), the research arm of the U.S. Defense Department, to develop the PowerSwim, a high-efficiency, human-powered propulsion system for combat and reconnaissance swimmers. A fiberglass spar (pole) clamped between the calves holds two oscillating foils of carbon fiber, a wide one at the hips and a narrower one at the feet. A shallow squatting motion makes the foils undulate, creating vortices that push forward against the trailing edge and provide thrust.

This design uses the largest leg muscles instead of just the calves and ankles, says DARPA Defense Sciences PowerSwim Program Manager Lt. Col. John Lowell. Top speed is about 2.5 miles (four kilometers) per hour, which still works with scuba gear, but more important, the PowerSwim is 70 to 75 percent efficient at translating effort into propulsion. "We're getting to the point where its getting harder to imagine getting much better than that," Lowell says. DARPA hopes to have working prototypes ready for military divers to test by the end of the year.

Ciamillo is also planning a demo the Lunocet for the Marine Corps's amphibious unit, and is continually refining the fin's pitch control mechanism, which dictates the angle between fin and feet, in an attempt to improve efficiency and speed. He notes that he won't be patenting the Lunocet's design. "If you're taking ideas from nature," he says, "how can you then go to the patent office and say these are mine?"

My screenname "finny" came from "finfreak," and that name comes because I am a monofin freak, and the lunocet is the latest evolution of the monofin. NO offenense to you, but believe me when I tell you that this video is a super-duper CRAPPY exhibit, and if you read the comments on the lunocet website, you'll see that folks who know swimming beg again and again of the company: Why don't you get some real swimmers to demo the thing??

I'd love to try a lunocet. You can haul ass with a monofin if you know how to do it, and the guy in this video most emphatically DOES NOT KNOW HOW TO DO IT. Not even close. He is totally inept, and why lunocet has so many very, very, extremely inept swimmers on their video demos is beyond me.

Top speed with a monofin the last I looked, which was a few years ago, was about 7 knots. The ability to swim 50 meters -- that's a l-o-n-g way!!! -- in about 14 seconds. I can't go that fast by a long shot, but then again, I'm not a competitior. But I'll tell you again -- one can really haul serious ass with a monofin. They are a blast.

Go to www.finisinc.com -- that's a website you can check out (won't try to link it because I'm too lazy).

See my post 21. That's a monofin. The main maker is Finis, and it makes three main kinds of fins. There's the "Shooter" fin, which is good for training butterfly stroke. There's the "Trainer" fin, which is a narrow but long fin and very good for strengthening the core; I have one of those. Then there is the lovely, incredible, fabulous Competitor fin, the big wide fiberglass beauty which, it sounds to me, is like the one you were looking at. I have one of those, as well.

Two other kinds of monofins from Finis are much less expensive and a really the best way for novices to learn the fun of them. The Tempo and the Rapid. I am going to buy a Rapid as soon as I can -- my other two fins are carbon fiber and fiberglass -- one can really only use them in large pools (or the ocean), the deeper the better. The little Rapid and Tempo are soft plastic and won't threaten to slice another swimmer's leg's off in a shared lane! (been there, done that!!!)

Understand that in true monofinning, for best results your arms should be streamlined above your heads, elbow locked -- second choice is to put your arms at your sides. If you attempt to use your arms as you would in a butterfly stroke, you will only slow yourself down unless you are using the Shooter fin, which was designed to help swimmers learn the rhythm of the full butterfly stroke.

I am a finfreak of sad proportions! Been pretending I'm a dolphin (I even have a broach cetacean breath-take of my own invention as I roll through the water) with monofins and regular fins for about 15 years. I'd love to try a lunocet in a large, deep, warm, clear body of water.

Apology if I came across antagnostic toward you! I'm glad you linked the site and the video! I found it a few months ago and was dumbfounded at how such a cool invention, that fin, could be demo'd by people who clearly had zero idea how to use it. Like giving a set of golf clubs to me and asking me to demo them!

Anyhoo, sorry if I got carried away and sounded snippy in my passion for monofinning. Really, it is a blast. I highly recommend it.

... if this thing is more efficient than a rigid marine propeller, what kind of work is being done to improve marine propellers? Anybody working on propelling ships with fins instead of propellers?

I think it's that propellers can push forward (or pull backward, even) a fixed thing, like a boat hull. Fins require some kind of undulation in the thing it is propelling. In streamline monofin swimming, the fastest guys use their stomach and back muscles as much as they do their leg muscles. It's a kind of whip motion that starts with a shrug in the shoulders and ends at the tip of the fin. Perhaps the Lunocet has a whole new set of dynamics, I don't know. I'd sure love to try one.

I am really intrigued at the description in the story of the PowerSwim propulsion project, and how these guys are using their leg muscles. Calves and ankles are heavily taxed in regular fins, but other muscles have to have dominance for monofinning. I can sure see why the PowerSwim as described would be valuable, though I can't picture the contraption in my mind. I bet real streamlined super-fast monofinning could never jive with scuba diving because of the weight belt and the tanks interfering with the undulation.

The picture at the top of this post shows a guy with a regular side-mount snorkel. Monofinners use a center-mount snorkel so it doesn't drag in the water. There are tremendous amounts of torque in the speed and resistence of the water, and drag is pretty important. I see the guy wearing that snorkel and wonder ... Hmmmm.

I wish I'd seen the Discovery program on it!

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