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.

11.11.2003

Full steam ahead in the trade winds….

"We're really pleased of the way we sailed through the archipelago of Madeira" explained Marc Guessard. "Together with Sylvain Mondon from Météo France, we sneaked a good path through and have managed to get back into the running. We've caught up with and even overtaken the boats who set out before we did. Now we're in the trade winds and sailing r…

par Gitana

"We’re really pleased of the way we sailed through the archipelago of Madeira" explained Marc Guessard. "Together with Sylvain Mondon from Météo France, we sneaked a good path through and have managed to get back into the running. We’ve caught up with and even overtaken the boats who set out before we did. Now we’re in the trade winds and sailing really fast".

If you look at the position data every couple of hours, you can see that Gitana is sailing fast. Almost 350 miles (648 km) covered in 24 hours, an average speed of 19.7 knots per hour (36.5 km/h), things are damp on board. One hand on the helm, the other ready to free off the gennaker sheet to cool things down if the boat should suddenly yaw off course. “The boat is in perfect condition. In the last two hours, we’ve made an average of 25 knots (46 km/h). We’re on a broad reach (wind blowing from an angle of 70°at a speed of 25 – 30 knots) with the main sail and small gennaker”.

Straight on towards the Equator !

Right now, the job in hand consists of reeling in 900 miles (1667 km) before attacking the trickiest pitfall of the second part of the course, namely the Doldrums. Marc is rather calm for what lies ahead. “We’re quite happy with our position in relation to the high. We’re steering a straight line course to the point at which we have decided to cross the Doldrums, whereas our closest opponents will no doubt need to gybe several times. We should be able to keep close to the rest of the fleet. However, once we get into the light fickle winds in the Doldrums, then it might well turn out to be a different kettle of fish altogether. But we’re giving it all we’ve got… If we can keep up with the main pack until the finish, that’ll be fine indeed”. Until Gitana reaches the zone known which used to be known as “the empty territory” in the times of the sailing ships, the temperatures have climbed and around lunchtime today, Marc was up on deck for manoeuvres in nothing but a pair of shorts. Time for a shower, radio chat session with those ashore since the intervention of the Gitana Team… Happiness is just a short step away !

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