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.

15.11.2003

Gitana well placed !.

A hobby horse race has been on since entering the trade winds yesterday. Concentration at the helm and never-ending sail trimming are top of the list to keep the boat sailing as fast as possible.

par Gitana

A hobby horse race has been on since entering the trade winds yesterday. Concentration at the helm and never-ending sail trimming are top of the list to keep the boat sailing as fast as possible.

That is apparently what has been happening on board Gitana since the end of yesterday afternoon. Lionel and Marc have pressed the turbo charge button, stealing into sixth place overall behind La Trinitaine. But at the 14h00 (French time) check-in, Sodebo had sneaked back and was leading Gitana by three miles (5 km). Daggers have been drawn, both crews fighting hard with less than 800 miles (1481 km) to go to the finish. Now is the very time when the crews have to be extremely careful to keep on track. Sailing fast downwind, the boats are spending most of their time with one float sky high. Steering in conditions like this is no mean feat. Rest is essential. Both sailors on board regularly take turns at the helm to get the most out of the machine.

Attack

With just 48 hours before the finishing line, the watches will get shorter and shorter and both crew will end up spending all of their time up on deck. Sylvain Mondon, Gitana’s router explained yesterday evening : “they’re full of beans. They’re pleased with their position in the fleet. The boat is in perfect condition. They’re ready to attack…”.
Instant speed readings are produced every two hours and prove that Gitana are constantly between 21 and 25 knots.
The boat’s course is the only marker of how things are on board for the moment as they have got their heads down for the home run to Bahia, and so there is no direct news from the boat.
Fleet leader, Groupama, is still expected to arrive tomorrow morning, Sunday 16th November.

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