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.

08.11.2007

Pit stop!.

At 15:30 this afternoon, Gitana 11, currently third out of the fleet of multihulls on the Transat Jacques Vabre, reached Puerto de la Luz on Las Palmas, Gran Canaria, for a express stop lasting scarcely 2 hours. The Gitana Team's technical staff were waiting there to change the boat's starboard foil, which was lost in the early morning of Tuesday 6…

par Gitana

At 15:30 this afternoon, Gitana 11, currently third out of the fleet of multihulls on the Transat Jacques Vabre, reached Puerto de la Luz on Las Palmas, Gran Canaria, for a express stop lasting scarcely 2 hours. The Gitana Team’s technical staff were waiting there to change the boat’s starboard foil, which was lost in the early morning of Tuesday 6 November.

The work involved consisted of removing the foil stub lodged in the float and replacing it with the spare foil. Olivier Wroczynski, William Fabulet and Sébastien Thetiot did not hang about… they were waiting for the boat, ready to intervene without delay. These seamless logistics enabled Gitana 11 to get back on her way at 17:15, by which time the ORMA fleet’s current leader Franck Cammas was just over 100 miles away from Gran Canaria.

Lionel Lemonchois, skipper of Gitana 11, at 17:00: “The foil’s been changed and we’re leaving in 20 minutes time. It all went well, with no complications. The technical lads saw to that. It was like being in a Formula 1 paddock, except that we’re in the middle of the ocean and they had to be very reactive, as up until yesterday, we were still supposed to be stopping in Madeira, not Gran Canaria. The aim now is to make up the time we’ve lost on the fleet’ leaders, with a boat back to its full potential! We’re up for it and back in the race more than ever!”

These technical stops are authorised by the race rules and the competitors are not penalised in any way on top of the stop itself. The race committee must, however, be informed of the boat’s decision and give its prior approval, as was the case here.

The weather to come by Sylvain Mondon (Météo France), Gitana 11’s router:

“The idea is to get back going as fast as possible in the hours after leaving Gran Canaria, by catching the trade wind originating in the south of the archipelago. The boat will keep changing tack while trying to remain in the windiest areas. After this stop, she has roughly 6 hours to make up on Groupama, which is more or less as expected. There are two thirds of the race still to go, so it’s game on!”

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