Above left: very ‘aero-driven’. A DSS board with hinge slots for the ‘aileron’ on the trailing edge, plus a pair of removable tips on the bench and a completed aileron on trestles awaiting fitting. The board is slotted into the mother-ship (above). The DSS board (left) exits through this PTFE bearing cassette and when retracted the cassette is then sealed off with a carbon plate. The slot is to accept the plug-in tip
detune the boat, with a more comfortable cockpit, a new cabin top and an interior, turning it into an IRC wolf in sheep’s clothing. At the opposite extreme was an ambitious programme to change the bow and stern, increase the length to 100ft, add more sail area and turbo-charge the per- formance as much as possible. Sitting between these two was a plan to make rel- atively minor changes, reshaping the bow and stern and exploring whatever perfor- mance gains could be made in the process. All three options had to meet a budget and had to utilise the existing mast, keel, winch package and deck (which was, in fact, originally from a previous 1990s 80-footer before being dropped onto the Nicorette). After considering the options the project’s London backers opted for the middle path, though in the end it did drift somewhat in the more radical direction… Bakewell-White’s first instinct in con- sidering the narrow hull form and inherent lack of stability was that it looked a perfect candidate for a Dynamic Stability System (DSS) installation. ‘It looked like a DSS boat without the board fitted. I felt it was a technology worth investigating.’ Although there was initial resistance within the group, Ludde grabbed the DSS idea with enthusiasm. Once the decision was made to go with a full surgical procedure, the Bakewell-White studio began a thor- ough VPP and CFD investigation of the DSS option, which looked promising enough to begin discussions with DSS patent holders
52 SEAHORSE
Hugh Wellbourn and Gordon Kay. Consideration also began into changing the rig configuration and, working in con- junction with Rodney Keenan from Evolu- tion Sails, the design group came up with a sailplan that effectively moved the rig aft by adding additional length to the forward section of the boat.
‘The overall length came up short of 100ft and some people have questioned that. But our approach was not to simply cut off the bow and build a new one to a pre-determined length. Instead, a more cost-effective approach was to slice off the first 1.5m and then make a series of longi- tudinal cuts into the hull, stretching back almost as far as the mast.
‘The internal framing in the forward section was removed and replaced with computer-cut frames conforming to a new extended bow shape. These were installed, forcing the hull skin to open up along the horizontal cuts rather like a banana skin to accommodate the new shape.
With the frames in place, wedge shapes were laminated into the hull skin, filling the gaps forced in by the bigger frames, long slender darts slotting into the spaces. The final length of 98ft was determined by where the port and starboard sides now met. To gain another 2ft would have meant more drastic surgery, cutting further back along the hull and removing one more frame, adding cost with little gain. One of the most distinctive aspects of the boat is the pronounced reverse bow,
which integrates with heavily chamfered forward upper panels and a long bowsprit in an aggressive, futuristic aesthetic. The treatment is very pleasing but, like virtually all the design decisions, was driven more by pragmatic considerations than by fashion; the imperative to retain the original deck meant the bow had to curve back to meet the deck, hence the reverse profile and chamfered topsides. The aft end also underwent major surgery. The first objective was to reduce the fairly pronounced rocker and flatten the run aft. The second aim was to increase beam at the transom. A similar method of splitting the hull skin and inserting new aft framing and a new transom was adopted, with fillets again added to fill the gaps. No additional length was added aft, although by replacing the old sloping transom with a new vertical shape the cockpit area was considerably extended.
Further attention to the aft area came as a result of testing sailplans in the Auckland University wind tunnel, which confirmed the benefits of widening the sheeting angles for the large reaching sails. Consequently, side wings were added to either side of the transom, projecting the aft sheeting angles out by 700mm on each side.
The decision to retain the original mast had a direct bearing on how much load could be carried when applying the extra righting moment generated by the DSS board and a deeper keel; the original draft of 4.5m was extended to 5.8m with a new keel fin milled by BAE Systems from Strenx steel custom ‘brewed’ for this project by Swedish company SSAB. The 7.5 tonnes of lead from the original bulb were melted down and used again but with a more refined bulb shape. The cant- ing mechanism, which can move the keel
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