Rudder with winglet is 700 euros ex VAT.
Size is 22 cm long 5cm wide in the middle and 3 cm wide at the tip. Thickness is 5 mm.
Position is in the back of the rudderblade, for better handling while sailing off the beach or out of the harbour.
Safest angle is perpendicular on the leading edge. Than the winglet is neutral while going flat downwind with a slight bow down trim. This position gives maximum pitch stability. Once the boat starts flying completely you might want some more lift on the winglet.
Vertically you have two options. Having both winglets in all the time or having the weather winglet out of the water all the time. Sofar we prefer both in.
The effect of the winglets on the pitching is amazing. When Mischa, PJ and I tested it we all started laughing as the effect was so huge and life became so simple. In testing the winglets did not slow the boat down downwind while going flat.
Winglets on the rudders work only on a multihull if you have curved boards, that's why we have not seen many winglets before. Without the winglets we would not have opted for J-boards.
It works the same as a rearwing on an airplane.
The winglets can be fitted on the 2012 rudders quite easily as these rudders are filled with foam. Just cut the hole and glue it in. We will supply the shape for the cut out. The winglets can be fitted to the first generation rudders, but you have to fill the blade around the cut out first before glueing it in.
We have changed the retaingclips from plastic to stainless steel on the new boats, but it works with the plastic retaining clips too. The force of the winglet is about 150N.