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.

12.11.2005

From island to island.

Gitana X is now underway once again after her pitstop in the Canary Islands after having replaced her mainsail. Gitana 11 is driving hard due south in direction of the Cape Verde islands. The trade winds are still rather powerful for both trimarans which are covering nearly 500 miles a day ! Next brain teaser is the approach to the Doldrums…

par Gitana

As one leaves the Canary Islands off her stern, the other is approaching the Cape Verde islands. Frédéric Le Peutrec and Yann Guichard have made a nice comeback on the leaders thanks to their African option. They are sailing fast down the coast of Mauritania where the NE wind is still blowing at more than 25 knots. It is still damp out there but the temperature is increasing with each mile. The aim now is to continue hugging the coast and try to sneak round the Doldrums.

Frédéric Le Peutrec (Gitana 11) at 6h00 on Saturday :

« We’re still sailing very fast at between 23 and 28 knots ! And yet we have shortened sail to avoid taking any risk. One reef in the main and stay sail up front as wind speed is still between 25 to 30 knots and the sea is still short and tough going. Waves break from time to time. Finding ourselves with no choice but to hug the coast seems to have paid off. On Friday afternoon we had to put a little west in our heading which we managed to do without any bother. The wind changed direction as we approached Africa and we gybed for the first time with a good run SW. A tricky second gybe and we are now plunging due south in a wind which should soon be shifting NE. We’re pretty exhausted though. We’ve not had that much chance to recover totally given the weather. We’ve even had to take on ballast (fill one of the ballast tanks with sea water), filling one of the aft tanks right up to balance the trimaran and avoid pitch-poling as Groupama-2 did yesterday. There are flying fish all over the place ! It smells a bit too. We can’t see them at night time so they land in the net or the cockpit. We have to clean up in the morning ! »

Thierry Duprey du Vorsent (Gitana X) at 9h00 on Saturday :

« We ended up spending more time in Puerto Calero marina off the SE of Lanzarote (Canary Islands) than we’d expected. We reached the marina at 21h30 on Friday evening, and had planned to get going again at midnight but the engine’s ventilator had brunt out. We had to switch it off and replace it. We lost two hours as a result. We’re beginning to clock up quite a list of hitches, too many for my liking ! Never mind, morale is still good on board. The spare mainsail in up and we’re under way again with 25 knots of wind and manageable seas. We’ll be staying in the corridor between the Canary Islands and Africa where there is more wind, just like Gitana 11. We’re diving down to Cape Bogador… In any event, this new stop over went perfectly smoothly as the technical team did a brilliant job once again. Fast, efficient and friendly. Next goal, the Doldrums ! There are still one or two tricks to try and pull off. »

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