Mini gauge foils
The Arkema 3 Mini 6.50 is a concentrate of innovations. Among these, the presence of foils is now made possible by the gauge. Today it is the only prototype yacht, conforming to the rules of the Mini 6.50 class, with these appendages.
The gauge sets two rules:
- J-3 Width: The boat maintained at a zero heel, its width must not exceed 3 meters.
- D-6 Appendices: The appendices may increase the width defined in D-3 once the start is taken, but not exceeding 6.50 meters in the worst configuration.
In order to comply with these 2 rules, the foils are mounted on warheads. Their rotation allows the tip (2nd part of the foil, the outermost part) to be placed against the hull, in the starting position, respecting the 3-metre constraint. The shafts (1st part of the foil), retracted, are stored one on top of the other and then occupy the entire inside width of the boat, so much the worse for comfort! Once the race has started, the skipper can take out the foils and adjust the incidence.
3 D adjustment
While sailing, Quentin Vlamynck, skipper of the Mini 6.50, can adjust the position of the foil in almost any dimension. The appendix is held at two points, in the ogive on the shell plating on the one hand and on a 'flying' frame at the end of the shaft on the other. Using a system made up of several hoists, taken from the boat's interior structure and sent back to the cockpit, the skipper controls the position of the frame, just like a sail-pulling point. It can retract the foil more or less to vary the bearing surface. By changing the height of the frame and its longitudinal position, it regulates the incidence and the force generated by the appendix.
To complete the balance of the sailboat in flight, fixed ailerons are placed on the rudders. Adjusting the rudder assembly on its fitting allows you to vary its incidence in relation to the water.
The long flight
The Lalou Multi Team within which Arkema 3's project is being developed has been discreet about the performance of its Mini Steering Wheel. Indeed, the foils are only one aspect of the project and the aim is above all to make a reliable and high-performance ocean racing boat for the Mini Transat. Average speed must prevail over flying at all costs and beautiful images.
However, the results are very encouraging and if the planning prevented the boat from competing in 2016, 2017 will be instructive. The performance observed in convoying at over 20 knots augurs well for some fine races. Nevertheless, the team remains cautious and reminds us that we should not jump to conclusions one way or the other, as the weather is crucial. Appointment is taken on the pre-season races.
