Design
A competitive commission...
Mark Mills describes design development of his aggressively targeted new 62-footer Super Nikka
In late 2013 we received an email enquiry from Italy for a design in the 60ft range. As we learned more about the client and his team the pieces began to fit together to form a very promising and productive design opportunity. A brief for a high-performance racer-cruiser is always a difficult request, often compromising both sides of the equa- tion, but this client was a little different… Roberto Lacorte is a very dynamic indi- vidual, a successful businessman who also drives for the Sport Prototype motor racing team he sponsors, races his 2012 Vismara 47 Lady Nikka as well as cruising it in summer with his family; and when he felt there was too little offshore racing in north- west Italy he founded the now-thriving 151 Miglia Race.
This race, plus others like the Giraglia, the Rolex Middle Sea Race and the Maxi Worlds, framed the target for Lacorte’s new design, in a vision not just to combine racing with cruising, but to create some- thing powerful and beautiful to do both in. The new boat had to look extraordinary as well as race effectively when not fully fitted out for family cruising. In cruising trim the requirements included sub-3m draft, powered winches, dinghy storage in the
46 SEAHORSE
transom, a retracting bow thruster and an anchor windlass, on top of the two ensuite double cabins aft and the master suite forwards.
To get a feel for his options at this size Roberto chartered the 65ft Stig for the 2013 Middle Sea Race and placed second overall entered as Nikka 65, confirming the team’s skill and learning a lot about what they wanted from their new design. At the core of Roberto’s team is builder Alessandro Vismara, head of the large Vismara Marine facility in Viareggio where he has produced two of Roberto’s previous boats. The design responsibility would be a joint effort with Vismara, an experienced designer himself whose large technical office had already produced a detailed preliminary layout for Super Nikka. This allowed us to focus on our strengths in producing the external geo - metry for hull and deck, appendages and rig sizing while the Vismara team pro- duced the structures, layout and systems. At the outset we agreed that the basic boat needed to be as aggressive as possible and concentrated on separating the racing and cruising configurations by making much of the cruising gear removable – including the anchor windlass and replac- ing the transom door/swim step with a lighter panel. Draft would also be max- imised with a lifting keel arrangement, lowering the bulb to 4.2m. Armed with a target racing measurement condition displacement of 16,150kg and resulting weight distribution, we could begin to
shape the design around these initial requirements.
To develop the Super Nikka hull and appendages we relied on the development programme originally created with perfor- mance prediction and analysis experts KND/Sailing Performance for our 2014 Maxi 72 World Champion design Alegre. This process is now a fundamental part of our performance design procedure, and begins with an analysis of the weather con- ditions and expected racecourse types to build a weighting matrix favouring perfor- mance in the particular conditions we want each boat to excel in. This racing event profile was Mediterranean and primarily offshore, suggesting a light/medium-air bias and a more even mix of wind angles than our more usual inshore windward- leeward orientation. This larger reaching component favours a wider, lighter boat, with chines, and a healthy sail plan to keep moving though a quiet Med offshore night. Working with KND partner and panel code specialist Roland Kleiter and using custom aero coefficients from the design- ers at North Sails Italy we began to analyse a range of hull shapes using the North Sails VPP. We started with a development of Alegre with soft chines set well inboard, and began sequentially comparing that with more aggressive shapes using more powerful chines further outboard – which proved to be very effective upwind. Over more than 20 iterations we developed the harder chined hull form until we were happy that it presented
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