R=

L+2d-F+√ S 

2.37

Every 2.4mR has to comply with the International ISAF rules. The basis for this rules is a formula that has e.a. sail-area and geometry of the underwater hull as input. The outcome of this formula has to be 2.400. This means that a larger sail-area influences the allowed shape of the underwater hull ) length waterline.

As a result of the many years of experience the designer managed to tweek the different parameters in the formula to a optimum that resultes in a total different sailarea and geometry compared to the current designs that are currently on the market.