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.

08.05.2005

A tightly-packed fleet in the prelude off Groix.

Superb conditions for the coastal course as a prelude to the long passage covering 2 600 nautical miles from Lorient to Nice. The IB Group Challenge had planned a short course between Groix and the mainland for the spectacle and for the public. Franck Cammas came out in the lead at the Pen Men headland (Groix), but Gitana 11 was the first behind, l…

par Gitana

Calm sea, lively breeze, sunshine. What more could you ask for on a 3 o’clock start on a Sunday afternoon as the six strong fleet of trimarans set out on a ten mile prelude course which they covered in less than 45 minutes ! A twelve to fifteen knot westerly wind, increasing steadily to 18 knots, almost an identical line to the prologue the day before. And almost an identical situation. Franck Cammas (Groupama 2) got off to the strongest start, leaving Pascal Bidégorry (Banque Populaire 4), Frédéric Le Peutrec (Gitana 11) and Thierry Duprey du Vorsent (Gitana X) to leeward.

Michel Desjoyeaux (Géant) had a tough time of it once again slightly behind with Armel Le Cléac’h (Foncia). Not an easy position to maintain in the long term if you want to avoid losing a lot of ground as they were receive wind spoiled by the leaders. So Géant opted for a speedy change of tack towards the island of Groix, whilst the rest of the fleet was bound for the Talus headland. By the time they reached the windward mark 5 miles off, things had changed again as the peleton had squeezed together behind Groupama-2 who had come closer into the island for a while. Géant only just managed to push ahead of Gitana 11, with Banque Populaire, Foncia and Gitana X hot on her heels.

A long stretch with the gennaker up later on, for another five mile stretch in a breeze which was getting stronger all the time. Franck Cammas confirmed his breakaway as he had almost a four minute lead over a group of three trimarans who were very close together indeed – Géant, Banque Populaire and Gitana 11 followed not even two minutes later by Foncia and Gitana X. yet another tacking session to leave Groix to port and make headway to the Pen Men headland. Wisely indeed, Yann Guichard, tactician on Gitana 11 decided to change tack first which brought her into the lead of the chasers. The others were never far behind as Foncia and Gitana X were still hot on her heels.

Then the trimarans shook out some canvas to plunge SW towards Cape Finisterre on a very fast leg (more than 25 knots) but the westerly breeze should soon change direction to the east, strictly the opposite ! So, we can expect a transitional zone before the start of the night without much wind, shortly before the wind picks up slightly yet again. The easterly wind will propel the fleet at a good speed towards the NW of Spain. Easrly on Monday afternoon, they should have reached Cape Finisterre. An exciting race in store as there are plenty of occasions for the cards to be reshuffled, lots of tricky weather situations, lots of tactical options.

Rankings at the leeward mark :

1-Groupama (41′ 58”) 2-Géant (+ 3′ 44”) 3-Banque Populaire (+à 3′ 59”)
4-Gitana 11 (+ 4′ 18”) 5-Foncia (+ 5′ 39”) 6-Gitana X (+ 6′ 36”)

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