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.

05.04.2006

Gitana 11 optimised.

Using all the experience acquired during two seasons on the Gitana 11, Frédéric Le Peutrec and the entire Gitana Team have carried out major works on the trimaran, stripping it down entirely and grafting on a new central hull bottom. This Monday 3 April, the boat was relaunched on the evening tide at Saint-Philibert.

par Gitana

Realising that the Gitana 11 was still a high-performance sailing boat, very sound and easy to steer in the wind but lacking scalability in a light breeze, Frédéric Le Peutrec and Antoine Mermod (research & development), together with the architects VPLP (van Peteghem-Lauriot Prévost), looked into ways of alleviating this deficit without damaging the boat’s overall potential. The most technically straightforward solution, already applied to Michel Desjoyeaux’s trimaran last season, consisted of cutting the central hull above the water line and grafting on a new bottom. The aim was to raise the Gitana 11 in the water by increasing the volumes, with the original highly pronounced “V” shapes becoming more supportive “U” shapes.
The “rake” effect when changing tack and gybing should therefore be significantly reduced, allowing the Gitana 11 to move more easily without being blocked when tacking. This phenomenon used to result in inferior acceleration after manoeuvres and consequently more problems controlling rivals on the water, getting out of tricky situations or opting for a short tack, etc. These small minuses, added to a difficulty relieving the central hull by less than eight knots of real wind (and the Orma 2005 Grand Prix saw primarily slow winds) placed the Gitana 11 in difficulty several times, at Marseilles, Vigo and Fécamp.

Since this decision was taken even before the start of the Transat Jacques Vabre, the Gitana Team have had a new central hull bottom made, with all the work over the winter being carried out at its Saint-Philibert base. Taking advantage of the arrival of the Gitana 12 (ex-Bonduelle), the technical team has acquired a new machine that strips paints and coatings by projecting starch powder. As a result, the Gitana 11 was stripped totally “bare” (down to the external carbon layer) in order to reduce the weight, then the central hull was cut approximately fifty centimetres above the water line. At the same time, the centre-board box was also modified to adapt it to a new shorter profile but with the same draught (5.00 m) by reinforcing the mid-shaft structure.
The overall improvement in terms of weight on all these items comes to approximately 200 kg. Parallel to this, a new centre-board was constructed, a central ballast of 500 litres installed to bring it into line with the new Route du Rhum regulations, the floats strengthened, the whole of the rigging (dormant and current, i.e. guys and lines) changed, and the hydraulic mast transfer system re-examined to accelerate the swing manœuvre. Lastly, a changing programme was set up for the validation and pooling of parts with the Gitana 12 (sails, rudder blades, etc.…) by means of joint testing once the trimaran led by Thierry Duprey du Vorsent has left the boatyard on 14 April.

Frédéric Le Peutrec and his crew will therefore be devoting the coming days to testing this new version of the Gitana 11 at sea, before participating in the training session at Port-La-Forêt from 18 to 21 April. The trimaran will then head for the English capital to take part in the first race of the Multi Cup 2006, London-Alpes Maritimes, scheduled to start on 8 May. The skipper will be joined on this 2,500-mile seafaring event by Baron Benjamin de Rothschild, François Denis, Daniel Souben, Ronan Le Goff and Fred Guilmin.

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