displaces 11tonnes as against 12tonnes for Sodeb’O. At 29m length overall, IDEC2 is


slightly shorter than Sodebo’O, which is 32m long. Both craſt have a larger length- to-beam ratio than the previous genera- tion of maxi trimarans being scarcely any wider, for example, than B&Q which was 22m long. Te narrower vessels can get up on one hull more easily, reducing hydrodynamic drag. Te greater length, especially in the


main centre hull, increases the ability to drive the yachts hard with less fear of pitchpoling when running at speed. Both vessels have carbon composite masts, IDEC 2’s being about 100kg lighter than that of Sodeb’O, and composite (Kevlar and PBO) rigging.


Speedy mono Mutihulls have long had a reputa- tion for speed, but monohulls, in new forms enabled by composites, have been catching up. A case in point is Hugo Boss, the Open 60 class mono in which Alex Tomson and Andrew Cape came second in the recent two-handed Barcelona World Race. Tis craſt, made from carbon/epoxy


Hugo Boss is 25% lighter than previous Open 60 incarnations (courtesy of Gurit UK).


relatively highly specified shell structure of Sodeb’O, Airex structural foam and Baltek end-grain balsa, used in various densities, were the sandwich core materials. Laminates, laid up on male moulds,


were designed with f ibre content optimised to meet targets for weight, stress, and impact loads and other design parameters. Laminated items were cured under vacuum at relatively low tempera- tures. Rudders and foils were built to precise profiles and laminate details. To minimise construction time, interior bulkheads and floors were produced as composite panels with Nomex cores and carbon skins, and were supplied by ATL Composites as CNC routed kits. Tere are other differences too. In line


with Joyon’s own personal inclination, IDEC is simplicity itself compared with


Ship & Boat International May/June 2008


his rival’s Sodeb’O. She has a conventional mast rather than the canting mast opted for by Coville. IDEC 2’s rudders, recycled from an old 18m trimaran, contrast with Coville’s rudders and foils which were new and engineered in composites specif- ically for the intended task. Te interior on Joyon’s boat, though


practical, is somewhat ‘home-spun’. Caring little for media profile, Joyon elected to do without the satcom dome and other communications parapherna- lia that have become de rigeur for ocean record attempts, relying instead on an Iridium phone and e-mails. Tis, along with the use of solar panels,


a wind generator, and a hydrogen fuel cell in place of an engine and alternator, saved around 800kg in machinery and fuel. Indeed, Joyon used no fossil fuel during his ‘green’ circumnavigation. IDEC 2


prepreg and aramid core, is capable of 35knot bursts when surfing - speeds which, for a monohull, would have been unthinkable a few years ago. Modern composite fabrics and resins have made it possible to produce forms that resemble large, beamy skimming dishes aſt transi- tioning to vertical wedges forward, having all the keel weight concentrated in a bulb located well below the hull where it can exert the greatest righting moment. In fact, like many of her competi-


tors, Hugo Boss has the canting keel that is rapidly becoming the technol- ogy of choice for shiſting weight to keep performance yachts upright against a press of sail on either tack. Designers Finot-Conq took great care


and used experience gained from keel breakages elsewhere in designing this safety-critical item. Careful specifica- tion of materials along with manufactur- ing and installation details should, it is hoped, ensure that this highly-stressed component remains attached and operational. Success in the recent round-


43


Feature 4


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