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.

14.04.2005

Gitana X qualifies.

Thierry Duprey du Vorsent and Erwan Le Roux made it back to safe harbour in the small hours of Thursday morning after a passage four and a half days long qualifying for the Transat Jacques Vabre. Meanwhile, Frédéric Le Peutrec was training with his crew in Port-La-Forêt.

par Gitana

After having covered more than 1,300 miles mainly close-hauled and fetching, here is a summary of Gitana Xs first outing after her winter refit. A positive summary from a point of view of gear and the guys sailing her, both of whom will be lining up on the start of the Transat Jacques Vabre on 6th November bound for Salvador de Bahia (Brazil). Erwan Le Roux describes the eventful passage :
We had to do a U-turn after having made a false start as we spotted a hairline crack on the boom. We preferred to check it out rather than run the risk of breaking but it turned out to be nothing to worry about. So we got underway again on Saturday morning on the tail end of a depression in a 15-20 knots norwesterly wind to round the first waypoint (an imaginary mark imposed by the organisers of the Transat race) lying NW of Cape Finisterre on the northerly edge of the high pressure zone. After a long leg fetching in crosswinds, we ended up close hauled as the wind veered SW with 15-20 gusting from time to time up to 25 knots in heavy seas, chaotic cross seas. Quite a test for the boat !
The next stage of the passage took us west of Ireland over to a second waypoint in westerly breeze which veered to a 15-20 knot NW, still beam reaching, we sailed with one reef in the main and with either the solent jib or the staysail up, depending on the wind. On our sail back down to La Trinit/Mer, we had the gennaker up for two hours, then beam reaching once again for 400 miles.
Gitana X sails well and we learnt how to use the mast rake to our advantage (the angle the mast leans forwards or aft, thereby changing the centre of the sail plan and the fore and aft trim of the boat as a result). The trimaran reacted well without needing to play around with central rudder foil angle. Everything worked well with the odd exception here and there, minor details really (snapshackle, steering cable and so on). This passage gave us the occasion to validate how she sails on the open sea.

Frdric Le Peutrec and his crew on Gitana 11 completed their second training session alongside Groupama-2 (Franck Cammas) and Banque Populaire-4 (Pascal Bidegorry). Foncia (Armel Le Clach) had split his dagger board and Gant (Michel Desjoyeaux) was having her mast stepped to were unable to take part in this session organised by the Port La Fort Sail Training Centre. According to Yann Marilley, trimmer on board Gitana 11, the trimaran is at ease in a breeze but lacked a little punch as her central rudder is small (designed for offshore racing). On Wednesday, Gitana 11 flew along wind abeam at average speeds of more than 37 knots, handling particularly well ! The trimaran should be returning to her base in Saint Philibert on Thursday afternoon.

On Sunday, Gitana X will be setting out for Saint-Nazaire on an attempt to beat the SNSM record (the French national lifeboat association), a new event in which Gant, Groupama-2, Sodebo and Banque Populaire-4 will all be taking part. The profit-making race is open to all sail boats and will be inaugurated on Tuesday 19th April for the ORMA trimarans over a 284 mile long course from Saint-Nazaire to Saint-Malo. Gitana 11 will not be taking part in spite of the best will of the crew for her to do so, because the boats new trimmer fitted dagger board has to be finished at the CDK yard before the first ocean race, the IB-Group Challenge (Lorient-Nice, start on 8th May), a race which counts towards the Multihull World Championship.

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