Safety: Making a Case for a ‘SOFT’ Forefoot March/April 2017 MULTIHULLSREPORTING ON CATAMARANS AND TRIMARANS WORLDWIDE SINCE 1975 www.MULTIHULLSMag.com Francis Joyon Takes the Jules Verne Trophy Also in this issue: www.multihullsmag.com | MULTIHULLS Magazine Slyder 49 • Spectrum 61 • Dubois Nacarat • Sunreef 40 Open Power • Schionning G-Force 2000 CONTENTSMarch/April 2017 • Volume 43 • Number 2 MULTIHULLS FEATURES DEPARTMENTS 4 NEWS BRIEFS: 28 SLYDER 49 • Multihull Solutions Cruising Rallies This sporty new modern cruising catamaran • Aeroyacht Expands Power Cat Fleet features two aft helm stations and makes it • ASA Certifications in the Caribbean easy to sail single handed. • Henneke Boon to Attend Hui Wharram • Sunreef 68 Wins Award 30 SPECTRUM 61 • Fountaine Pajot MY44 Wins Award Naval Architect Albert Sedlmayer has • Hyde Sails Expands designed a 200-foot superyacht that features • JFA Yachts Becomes a “Living a floor iris, infinity pool, piano lounge, and Heritage Company” a THX theater. 14 FEATURED PRODUCTS: 34 DUBOIS NACARAT • B&G PredictWind This medium displacement cruising • Lowrance HDS Carbon 16 catamaran was developed to provide the • GoPro HERO 5 best of fast cruising and easily handled • IMTRA HI LED Deck Lights when short crewed. 24 SAFETY: 40 SUNREEF 40 OPEN POWER A CASE FOR A “SOFT” FOREFOOT A beamy alternative for classic day boats, The idea is to have a forefoot that shears this cat features two lateral aft folding off during impact to absorb part of the platforms. There is also a hydrofoil version shock and reduce the deceleration to something more tolerable for the boat and that can attain speeds up to 60 knots. personnel onboard. BY MIKE WATERS NA 44 SCHIONNING G-FORCE 2000 This sleek, carbon fiber catamaran comes in 52 RACING: at just under 20m in length and is 8.6m wide. JULES VERNE TROPHY: On the cover: AROUND THE WORLD IN 40 DAYS! Francis Joyon, Bernard Stamm, Alex Pella, Sébastien Audigane, Clément Surtel and Gwénolé 54 RACING: Gahinet pilot IDEC Sport in the NGALAWA CUP: quest for the Jules Verne Trophy. JANUARY 2017 EVENT Article on page 52. © Jean-Marie Liot / DPPI / IDEC 2 MULTIHULLS Magazine | March/April 2017 A Case for a ‘SOFT’ Forefoot For More Safety at Speed by Naval Architect Mike Waters asedn o a personal expe- like many other items were, that ocea n voyageu r. He is refe r r i ng he re rience of collision with ended up travelling 30 feet to the to relatively high-speed collision Ba huge underwater, un- forward end, and possibly been and most likely with a UFO (Un- charted rock some years ago that fatally injured. identified Floating Object). caused both boat damage and per- Here’s a photo showing the fail- So for any boat capable of con- sonal i nju r y, Naval A rch ite ct M i ke uren i compression of the skin – tinuous speeds much over 10 knots, Waters n was i the process of incor- virtually smashing the hull in two, he thinks the following concept is porating some defense against this with only the bottom of the boat worth considering and becomes within a new design, when he read a nd a very weakened deck , hold i ng even more justifiable for faster boats: about the horrific collision suffered things roughly in place.“ I call this ‘the SOFT forefoot’ – by a competitor in the recent Ven- Along with this story and the re- SOFT bei ng a n a c rony m for Shea r- dée Globe. He re is what he re por t ed alization that several other boats Off-Forefoot-Tip. in January 2017 under a “What’s in the same ocean race were also I have used this basic concept be- new for 2017” article posted on his damaged from such collisions, he foren o dagger boards in the 1990s website www.smalltridesign.com. was o pushed t share a concept that and has been shown in a sketch in “French sk ippe r T homa s Ruya nt he believes could save serious in- the Header on my ‘What’s New’ on board Le Souffle du Nord, col- jury in the future. webpage since 2008. lided with a low floating container Now this is not for every boat, The s idea i simple enough… To a s he wa s t r avel l i ng at a re por t ed 17 but with the hundreds of containers have a forefoot that shears off to ke not s! H was ext remely for t u nate now reportedly lost at sea from the absorb f part o the shock and reduce to be slee pi ng a nd t ucked dow n be - decksf o ships, ocean going sailors t he deceleration to somet h i ng more h i nd a ‘bea n-bag’ at t he t i me, so h is who also want to sail fast need to tolerable for the boat and personnel head was cushioned as it slammed seriously consider this added risk. onboard. Many existing slender into a forward bulkhead. If he had He personally considers Sinking, boats could be converted, with a been standing, he could well have Collision and Capsize to be the three straight cut made at 25-30 degrees been catapulted through the boat most challenging r isk s for t he a rdent – the final angle being decided by The damage to Le Souffle du Nord Diagram found on the author’s website Daggerboard Direction tip cut off at about 30 degrees A: Butt joint with thickened epoxy Rock B: Nylon shroud bonded to each part Sea Bed C: Diaphragm bonded B in watertight A C 24 MULTIHULLS Magazine | March/April 2017 A diagram of a W32 hull featuring a “Shear-Off-Forefoot-Tip” W32 Double Botttom with Kevlar ‘SOFT’ PU Foam the starting height up the stem and a ct somewhat l i ke a n icebreaker. T he rocks, as the foam-backed Kevlar- the feasibility of its extension aft. bonding I use is simply a thickened lined outer skin, will absorb the brunt The SOFT would then be bonded epoxy, with the filler tailored to give of the damage, while the inner skin back in place and the surface re- the required shear-off value. In the will retain the hull integrity. I suggest fairedo t be invisible – with the casef o such applications for dagger- that such design steps will add im- bonding being calculated to shear board tips, I’ve also built-in a small portant protection and significantly at a pre-determined load. I’d sug- watertight cavity into both the board lower the risk of collision with the gest considering something in the and o the tip, s that a long nylon cord numerous near-surface obstacles a order of 150 kg shock load, mean- can be attached between each part. fast boat can meet. ing it would resist a static load of In this manner, the tip is recoverable more than double that. Assuming and can be rebonded after serving About the Author the main risk was for containers (or its purpose, and be ready for another Mike Waters studied naval ar- similar) floating at say 300 mm or collision. chitecture at Southampton, UK less above the water, the slope of In f the case o a safe-fast-cruising to later become one of Canada’s the cut would allow the bow to lift trimaran design I am developing, leading ship designers. Parallel to sl ig htly a nd g ive i ncrea sed deceler- this boat uses a basically similar hull this, he built, sailed and designed ation space that would significantly form to that of the ‘simple but effi- sailboats since he was a teenager reduce t he i nitial shock. If cor rectly cient’ W17, so, except for the extreme and has been a multihull enthu- designed, this might still throw a bow, the bottom of the main hull is siast since 1976. Since officially crew off their feet, but the SOFT flat. In this case, the bottom for the retiring, he has published many attachments i a trade-off between forward half of the boat, will appear quasi-technical articles and still serious injury and something that as a composite panel with about 100 maintains an encyclopedic website ba sically st ays i n pla ce for all pr a c- mm of foam sandwiched between dedicated to small multihulls. His tical use of the boat. two bottom panels, and designed so unique W17 small trimaran design Naturally, the part of the boat above that the inner one will complete the can now be found in 32 countries. the cut must be refinished in robust essential boat structure. This means For more information, visit: http:// fashion and effectively, the boat with- that such a boat will have a strong www.smalltridesign.com or e -mail: out the SOFT in place, will look and abilityo t survive even grounding on [email protected] MM www.multihullsmag.com | MULTIHULLS Magazine 25.