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.

02.06.2004

In search of lost wind.

Two nights into the race and the situation is starting to shape up out on the race course. With the first low over, a ridge of high pressure has clearly slowed the fleet down, given the single-handers the chance to get some rest before the second low expected to reach the fleet this evening. A few hours later than the leading boats, Gitana 11 picke…

par Gitana

A brief pause is always heartily welcomed after a lively start followed by the dampness they had on Monday. But as ever, this is the calm before the storm. Fred Le Peutrec has been able to rebuild his strength, rest, work on the weather charts, anticipate the strong breeze forecast for Wednesday evening . « I’m into the swing of things now. I’ve been able to get some sleep, eat and helm, observe what is happening on the water. Within the next 24 hours, the going is going to get tough ! yesterday’s ridge of high pressure meant that we were able to dry things out on board as it had been really humid indeed. » explained the skipper of Gitana 11, at 8h30 this morning.

Lying in wait, as it were, the trimaran might have lost a bit of ground to the leaders, Michel Desjoyeaux and Thomas Coville, m but this difference is mainly due to the weather difference. The wind came in earlier than expected for the leaders settling slowly but surely towards the east. Then there is also the difference in longitude, the advantage being given to the head of the fleet. So the 30 mile difference on Tuesday had increased to 110 miles just twelve hours alter. As the leaders were making more than 23 knots at 7h00 this morning, the rest of the pack was still moving at around ten knots. But this phenomenon is subject to variable. It’s like a piece of elastic, as the fleet leaders will be the first to be slowed by the arrival of the coming low pressure system.

« We’ve had to play around with the light air overnight in search of stronger wind. I made the mistake of changing tack a little too early as I though that the wind was settling. In fact, it was just starting to make its way in. » explained Fred at 8h30 this morning. «The fleet has been split in two. One in the north with Géant and Sopra Group ; the other to the south with Banque Populaire and Tacchini. I’m between the two groups in a wind coming from 190° (S/SW) at 10-12 knots and it’s picking up gradually. »

As for Marc Guillemot who was within sight of La Trinité sur Mer at 06h00 this morning, not wanting to disturb his shore crew with a wake up call too early on in the day, he made for the open sea again and is making the most of it to get some rest. Gitana X finally came into port at 11h45 in brilliant sunshine, welcomed by the whole of Gitana’s technical team – Jean Le Houérou-Kérisel, Laurent Bourgues, William Fabulet, Léo Lucet, Jean Pierre Trottet, Thierry Duprey and router, Yann Guichard.

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