Retractable Y-shaped foils, adjustable in three dimensions

Inspired by the appendages of the America's Cup foiling monohulls, these Y-shaped foils have a wingspan of over 5 metres. They are designed to generate powerful lift, increase power and offer a wide range of adjustments to optimise flight at every point of sail and in all conditions. Beyond their impressive size, these foils feature many unique innovations.

Revolutionary U-shaped rudders

These are probably the most visually striking innovations on the new Maxi Edmond de Rothschild. To fly high above rough seas while maintaining control, the team wanted very long rudders that would remain in contact with the water. The challenge is that longer rudders tend to flex under load, severely affecting steering and the efficiency of their lifting surfaces. A new geometry was needed to give these appendages maximum stiffness, resist cavitation and ultimately improve control of the boat and make better use of its power. The result is a set of U-shaped rudders over 4 metres long, a metre longer than those on Gitana 17. Their shape, reminiscent of a tripod or an inverted π, is only the visible part of what makes them so distinctive.

A daggerboard optimised to stabilise the boat and limit cavitation

With its wide span, the daggerboard resembles an aircraft tail assembly, with two adjustable flaps: one on the vertical section and the other on the horizontal section, the distinctive “manta-ray wing”. On Gitana 18, the innovation is to position this wing behind the vertical part of the appendage, rather than directly beneath it, to minimise flow disturbance and cavitation.

Rig: adjustable spreaders to control mainsail power while sailing

Gitana 18’s mast is 1.50 metres taller than its predecessor’s. The boom is also shorter, creating a more slender sail plan. The major innovation is a set of spreaders that can be adjusted while sailing to bend the mast fore and aft. Actuated by hydraulic rams, these spreaders can pivot through 35 degrees to adjust the bend in the middle of the mast. This unprecedented system allows the sailor to control mainsail power: adding depth in light winds to take off sooner, or flattening the sail to reduce power at high speed or in strong winds. Adjusting the depth, and therefore the power, of the mainsail can also save a solo sailor time and energy by reducing the need for risky manoeuvres or headsail changes.

Central hull:
an integrated, structural coachroof

The naval architects and Gitana design team wanted an exceptionally stiff, structurally robust platform. This applies both to the floats, which must withstand heavy loads from the foils and rudders, and to the central hull, which is subject to torsion. The enclosed coachroof is integrated into the hull and contributes to its structural strength. Inside, the cockpit brings all sail-handling controls together, with ergonomics shaped by many hours of design and development. The coachroof also stands out for the number and size of its windows. This configuration meets the visibility requirements of the Ultim class rules and gives sailors the best possible view to keep a visual watch.

07.05.2005

An encouraging prologue.

Frédéric Le Peutrec and Thierry Duprey du Vorsent have every reason to be satisfied with this first « round » of the IB Group Challenge prologue raced this Saturday round the island of Groix in a nifty 12 to 18 knot westerly breeze.

par Gitana

Winter refit work has clearly paid off. Gitana 11 is not that far behind Groupama-2 (who finished just one and a half minutes on the prologue race round Groix. Gitana X has found her feet as she was hot on the heels of Géant, just 24 seconds behind ! Weather was perfect for this taste of what lies ahead in this 2 600 mile long offshore race, setting out tomorrow, Sunday at three o’clock in the afternoon. 12 knots at the start and a flat sea, increasing to 15 knots, to finish with gusts of up to 18 knots. Even the odd ray of sun shone on the granite cliffs of Groix. Superb !

Thierry Duprey du Vorsent did rather mess up the start in a laborious tack having opted to head off on the starboard tack to try and block the port fleet. Franck Cammas moved into the lead in the company of Pascal Bidégorry and Frédéric Le Peutrec, the three boats lining up for a very long beat upwind close to the coast of Larmor Plage. Michel Desjoyeaux was not on form, somewhat out of the game further behind, his air disturbed by the three leaders. In fact the going was so tough for him that Gitana X stayed tightly glued in for the first two rounds of the course. Foncia was not frankly ready and soon gave up the prologue.

So the match was played out by the three most finely tuned trimarans – Groupama-2, Gitana 11 and Banque Populaire-4. Their speeds differed little and it was essentially in the manoeuvres and tactical options that the hierarchy became clear. Frédéric Le Peutrec pulled off an excellent first upwind beat and even came in really close to Pascal Bidégorry’s bows just before rounding the headland of Pen Men, at the north-west point of the island of Groix. The crew of Gitana 11 even came back to within a few lengths of Franck Cammas. The finish confirmed quite how close the two boats are in terms of potential.
As for Gitana X, the performance of Thierry Duprey du Vorsent and his crew had clearly improved. Their tri continually put the pressure on Géant. See you on Sunday at 15h00 for the start of the IB Group Challenge, in a light to moderate northerly wind (thus downwind) of around 5-10 knots, due to strengthen in the Bay of Biscay.

Result of the IB Group Challenge Prologue

1-Groupama-2 (Franck Cammas) 1h 54′ 32”
2-Gitana 11 (Frédéric Le Peutrec) + 1′ 31”
3-Banque Populaire-4 (Pascal Bidégorry) + 4′ 02”
4-Géant (Michel Desjoyeaux) + 9′ 11”
5-Gitana X (Thierry Duprey du Vorsent) + 9′ 35”
DNF-Foncia (Armel Le Cléac’h)

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