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.

16.05.2005

Gitana – the comeback.

Frédéric Le Peutrec made a superb tactical move on Sunday in heading west towards Tunisia to latch onto wind backing from NW to S. Gitana 11 is now just astern of the leader and Gitana X has made it back into the peloton !

par Gitana

The Whitsun Bank Holiday weekend was marked by suspense in the IB Group Challenge. Firstly, fleet leader Groupama-2 broke her crossbeam just before Malta, then Banque Populaire made the most of a stern wind after the island to increase her lead to 130 miles and then finally, there was a neck and neck battle between Gitana 11 and Géant throughout the day and night of Saturday, both boats continually changing tack. On Sunday, a tactical divergence of opinion arose. Frédéric Le Peutrec headed off west towards Tunisia whereas Michel Desjoyeaux opted to hug the coast of Sicily. The moderate NW wind turned gradually W then SW and the African option turned out to be the one that paid off. To the extent that not only did Gitana 11 gain more than 60 miles compared to Géant, but in addition, Banque Populaire’s lead was a meagre 8 miles in the small hours of this Bank Holiday Monday…

As for Thierry Duprey du Vorsent, he made extremely good use of the wind shifts in the Strait of Sicily to head out west and round a windless zone where Géant was imprisoned. Gitana X was just forty miles behind Desjoyeaux-Le Cléac’h after having conceded as many as 150 miles ! Bravo…

Stretching out before the fleet is a two hundred mile long run downwind along the coast of Sardinia and Corsica in a relatively light southerly breeze. Gennakers up, thermal breezes to be managed close to the coast and the effects of the nearby relief. Not easy conditions to negotiate, rather the sort of situations where it is easy to get caught out ! Perfect conditions for the tail enders to start catching up and for the cards to be reshuffled. Moreover, finishing in the Ligurian Sea is far from being easy with yet another easterly breeze (wind abeam) of less than 10 knots… not easy on the nerves all these continual changes. By tomorrow morning, the five trimarans may well end up finishing in Nice within three hours of each other !

Thierry Duprey du Vorsent – Gitana X :

« Things went well overnight and I hope that it will pay off even more ! We are sailing in an easterly 8-10 knot wind which should be veering SE and strengthen to 12-15 knots throughout the day. This should be enough to bring us as far as the Bouches de Bonifacio.
We opted to go west to avoid a stretch of windless zones between Sicily and Sardinia. We also wanted to stand out from Foncia to try and overtake her by the west. It seemed to work as she is still not free of the wind hole… Just like Géant ! Now we have to handle the new S-SE flow which should be with us along the islands. The crew is highly motivated and a place in the top three is quite possible… »

Frédéric Le Peutrec – Gitana 11 :

« We’re really tired but really happy. I’ve got folks snoring around me ! We had a buffer zone effect overnight but at the moment we’ve got 11 knots SE. As we are coming back in with the wind, we should be able to gain ground on Banque Populaire. This new breeze should be with us to the north of Sardinia. We pulled off something cool in heading for Tunisia. We headed west to latch onto a W then SW wind rounding the calm zones which had captured Géant and to a lesser degree Banque Populaire. At one moment, we even thought we would pass in front of Pascal Bidégorry as he was stopped dead when we had 18 knots ! This morning , Géant and Foncia are still in the windhole. A nice stunt to pull off – a source of pleasure. »

Rankings – Monday 16th May 04h00 (French time) :

1- Banque Populaire (Pascal Bidégorry) 288 miles to the finish
2- Gitana 11 (Frédéric Le Peutrec) + 8.5 miles
3- Géant (Michel Desjoyeaux) + 71.2 miles
4- Foncia (Armel Le Cléac’h) + 76 miles
5- Gitana X (Thierry Duprey du Vorsent) + 115 miles
Abandon- Groupama-2 (Franck Cammas)

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