The fin is the sail in the water, without a fin there is no real directional control.
Heavy sailors need a bigger fin area just as boards with a wider tail do.
Fins are unfortunately not defined by area like sails are but length. When we compare different fin makes, we can see that there are huge differences in fin area at the same length (Figure 10). The length on the other hand influences the agility of the board.
Therefore, each board and condition requires an individual fin solution
Figure 10: Fin area and length for different fin products
As with every technical development, a scientific approach is required for fin development in order to develop a great product that takes into account the latest physics, R&D and testing procedures. Fortunately there are computational procedures available which allow us to calculate the foil characteristics with sufficient precision alleviating the need for expensive water tunnel tests.
But also fins designed and optimized with computational flow dynamics have to be tested under real conditions. Maui Ultra Fins are therefore constantly tested using GPS data and questionnaires which are completed by professionals and amateurs alike.
Only a high performance fin improves your board and your fun.
More speed, more grip, more fun.
I would like to say MAHALO to Michael Benkert, Gereon Westphal, Timm Köpke, Charlie Gilman and Bob Waterman for their valuable contributions and critical minds concerning this article.
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