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.

06.11.2007

The weather: an exact science?.

On Sunday 4 November at 13:02, Gitana 11 started out in the Transat Jacques Vabre. On board, Lionel Lemonchois and Yann Guichard already had a very precise scenario in mind with regard to the route they would take, developed in close collaboration with Sylvain Mondon, their router from Météo France.

par Gitana

All the sources of weather information had agreed on one thing: the start was going to be very calm. Slightly heavier and bulkier than her competitors, Gitana 11 did not stand to benefit from these conditions, as the blue trimaran is at her best in more sustained winds. Consequently, the Gitana 11 trio had devoted the final 24 hours before the start to developing a tactical response, and so it was that from 16:00 on Sunday, she moved markedly to the north of the fleet. This position caused widespread surprise, especially as Lionel and Yann then had to cross an anticyclonic bubble that slowed them down severely, with the result that they slipped several miles behind in the standings. But the crew had expected this scenario, safe in the knowledge that, come mid-afternoon on Monday, the wind would return more strongly from the north-west. At 15:00 on Monday, the trimaran did indeed encounter the expected wind and at 20:00 yesterday, she duly moved to the head of the fleet. This morning, she can be found zipping along at over 28 knots in the ocean off Cape Finisterre.

Sylvain Mondon, Météo France: “We were totally expecting this scenario. If Gitana 11 had set off on Sunday on the same course as Groupama and Banque Populaire, she would have had no chance under those conditions. Therefore, we made a conscious choice to leave to the North, knowing that the first 24 hours would be no picnic for us or the boat. But it was worth it as it has now paid off.”

Where the monohull fleet is concerned, Loïck Peyron and Jean-Baptiste Le Vaillant on Gitana Eighty are still lying third. But promisingly, between 04:00 and 08:00 this morning, the big monohull emblazoned with the Rothschild Group’s colours made up over 30 miles on the current leader Safran.

ORMA Ranking – Registered 5 at 12 AM
Place Bateau Latitude Longitude Vit. Cap Dist. But Dist. 1er
1 Groupama 43 12.36′ N 10 52.76′ W 22.2 209 3710.0 0.0
2 Banque Populaire 43 18.33′ N 11 28.92′ W 23.8 206 3714.5 4.5
3 Gitana 11 44 04.38′ N 12 38.26′ W 24.8 194 3732.2 22.3
4 Brossard 44 36.39′ N 12 31.86′ W 21.9 214 3762.9 52.9
5 Sopra 44 07.89′ N 11 02.21′ W 22.6 202 3767.3 57.3

IMOCA Ranking- Registered 17 at 12 AM

Place Bateau Latitude Longitude Vit. Cap Dist. But Dist. 1er
1 Safran 42 51.66′ N 11 15.97′ W 18.9 208 3695.5 0.0
2 Foncia 42 39.52′ N 10 33.90′ W 18.1 261 3699.9 4.4
3 Gitana Eighty 42 44.18′ N 10 33.41′ W 16.3 204 3704.1 8.6
….

Retourner aux articles

Heritage