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.

16.11.2002

Express repairs – High-tech and Ingenuity.

Suffering from structural problems, several giants competing in the Route du Rhum – all built in carbon - have been forced to make a pit stop. That's precisely when carbon and resin specialists have to intervene, in a commando-style operation : Olivier Staub, in charge of composites for the Gitana Team, explains the difficulties of such procedures.

par Gitana

Suffering from structural problems, several giants competing in the Route du Rhum – all built in carbon – have been forced to make a pit stop. That’s precisely when carbon and resin specialists have to intervene, in a commando-style operation : Olivier Staub, in charge of composites for the Gitana Team, explains the difficulties of such procedures.

“Marc Guillemot’s team, whose skipper (aboard La Trinitaine) is currently in the Azores for a technical stopover (due to cracks on the fore cross beam), came to us before leaving : they had a shortage of material”. Their emergency intervention within the race has to be perfectly prepared, they have to leave France with all the necessary gear, in order to be as self-sufficient as possible. The skippers generally do not stop in harbours where they know they can find the necessary means to carry out repairs, but in places that are least penalising route-wise. The Gitana Team had anticipated Lionel’s possible stopovers, in order to be ready.

Ingenuity required

“In the Azores, La Trinitaine’s assistance team will have to place a big patch of composites cloth on the cracks. It will be, as always in such cases, a work carried out with the means that are at hand ! The real problem concerns the work conditions : we’re outside, in the harbour, in a humid environment which temperature we cannot control. We have to imagine solutions, build a small shed to isolate the repair, and find the way to warm up the resin to have it harden. And all that as fast as possible, because the objective for the skipper is to be quickly back in the race ! Generally, this type of boats interest a lot of people in harbours and it’s always easy to find some help… It’s the nice part of that trade, we get to meet people we may see again in future stopovers”.

About Route du Rhum

www.routedurhum.org
www.france2.fr

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