Romaric Neyhousser’s rig on Arkema 3 is probably the first serious attempt at a two-element reefable soft wing. The current article looks quite clean and simple but to get there has taken thousands of hours of work. From main pivot to skin fabric, nearly everything has been custom made. America’s Cup teams learned early on the importance of finding skin materials that distort as little as possible and several new films were developed specifically to meet their requirements. However, the task is harder on a Mini because the skin must be soft to be reefable and meet class rules and also must cope reasonably well with twist in the main spar and trailing element


‘We are, therefore, limited to self-stabilis-


ing systems, with foils whose lift decreases as they emerge from the water.’ Verdier is looking to employ full flight ‘opportunisti- cally’, to develop a boat that will use its foils when possible but which will also be fully competitive when it is off the foils. And down in the Antipodes something


big is also happening. In collaboration with Advanced Wing Systems, designer and Seahorse contributor Nicolas Goldenberg has designed a foiling Mini that is currently being built in Sydney with the aim of being ready for the 2019 Mini Transat. The story is moving fast!


The Neyhousser soft wing We are quite used to boats experimenting with thick double-luff sails and even soft wings, but the rig designed by Romaric Neyhousser for Arkema 3 is the first of its kind to feature two elements incorporating a full slot system. The geometry and aero- dynamic operation are actually closer to the rigid wings propelling the C-Class and


America’s Cup catamarans, except that the wing panels are not rigid. On an ocean- going boat it is important to be able to reef and lower your sails… ‘This wing offers multiple benefits.’


explains the designer. ‘First, a gain in performance: it is well known that a thick profile can achieve a greater lift coefficient than a thinner profile, and that this coeffi- cient increases more with the use of two elements; the angle of incidence at which the profile stalls is also increased. ‘Then there is the greater ease of


control: the sheeting system does not involve such heavy loads as we are only changing the angle of attack; so it can be made more responsive to small changes.’ Neyhousser’s rig involves a freestanding


mast with four carbon hinge brackets that define the leading edge of the second element. Soft, non-structural battens help to induce the desired profiles. The ‘mainsail’ itself is attached to twin


grooves on the mast and by forced rotation of the mast the head of the ‘sail’


can then be opened up more than the foot to induce twist in the wing. The rear element pivots on an axis in


front of the trailing edge of the front element, and thus ‘the more the profile is cambered, the more the slot opens up,’ says Neyhousser, ‘just like an AC50 wing.’ The Arkema rig was built with Voilerie


Incidence, who created a custom polyester covering (class rules forbid other materi- als). ‘In any case, composite would not be desirable as twisting the rig will stretch the skin too much,’ says Neyhousser. ‘It’s complicated to develop… As you


see, when twisting we still have large folds appearing so there is a lot of work still to do to make it better aerodynamically. ‘We also need to consider the whole


way to go.’


sailplan in a different way; for example, instead of reefing the mainsail while keeping the solent, it might be more efficient to lower the jib and to continue under the wing alone… ‘It’s a very big subject and there is a long q


SEAHORSE 35


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88