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19. Mar 2018

Behind The Design – Flow S1 Foil

Behind The Design – Flow S1 Foil

Our SUP Wave Foil Flow S1 opens up a whole new world of riding waves. Catch barely breaking swell or fly over slower sections with power and speed – the S1 outperforms the conditions every time. We caught up with the developer Ken Winner about the design and R&D process.

What was your vision for the Flow S1?
The aim was to create something that would get SUP Foil beginners up and going quickly. We wanted it to be relatively small, light and strong, as well as big enough for foiling small surf. We were also set on using the existing Fanatic Foil Fuselage, Back Wing and Mast so those looking to get into surf foiling could do so with minimum cost. The Fuselage was not designed for enormous surf Wings, so we kept the total surface area and span to a size that the Fuselage can handle.

How was the R&D process?
We took inventory of our years of experience, along with the various Wing profiles and outline shapes that we’ve used in kitesurfing and windsurfing. We did some additional computer-based analysis of different profile shapes followed by some CNC-shaping of Wings and testing them on the water.
Fortunately the South side of Maui has a lot of small, novice-ready waves that are really perfect for SUP foiling and for testing Wing prototypes. I’ve never done any prone surfing and I’ve done very little SUP surfing, but I was foiling on waves with the S1 after about ten minutes of trying. I often rely on Patri McLaughlin and Sky Solbach for testing, but they are both excellent surfers and too advanced to see it from a novice’s point of view so we left them out of this one.

What challenges did you have to overcome?
In a sense, the challenges were small because we already had most of the components in place; Back Wing, Fuselage and Mast. With the S1 we only needed to worry about making proto Wings to test.
That said, making good prototype Wings requires CAD work to create the design, then CNC work to shape the Wing followed by fiberglass work to ensure that the proto Wing is strong enough.

What makes the Flow S1 stand apart from other Foils available on the market?
Since we wanted to get maximum lift for minimum Wing size, weight and cost, we went with a high-aspect-ratio outline and a fairly thick profile. The S1 gives as much lift as bigger wings on the market.

Can you tell us about the anhedral (droop) in the Front Wing and the Winglets on the Back Wing?
Starting with the Back Wing, the Winglets are there mainly to provide directional stability for kitesurfers and windsurfers. They aren’t really needed for surfing but we have them on the surf setup because of cost as it allows someone with a kite Foil setup to upgrade to surf by just buying a single Wing. For novices, the Winglets provide the extra directional stability.

Regarding the anhedral in the Front Wing, it does two things:
– It keeps the tip of the Wing further away from the surface of the water. This is really helpful when turning or traversing a wave face as the Wing is less likely to ventilate – breach the surface or suck air down from the surface)
– Anhedral also affects roll and turning. Since riding a Foil is a lot like riding a bike, roll and turning are closely related. Too much anhedral can give too much roll stability which makes turning difficult. No anhedral can give too little roll stability and make turning too easy. With the S1 we opted to go for more stability rather than less.

Who will enjoy it?
The S1 is the easiest and most cost effective way to get into SUP surf foiling. Any SUP novice can enjoy riding the S1 and it’s the perfect route into this exciting side of the sport.

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