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.

15.05.2003

D + 4 – Technical pit stop in Puerto Sherry (Spain).

In 7th position in the first rankings of the day, at 5h30 this morning, Gitana had to change course and head for Spain due to a broken dagger board. Close-hauled in a 35-knot (62 km/h) wind and a heavy sea, it was impossible for a trimaran handicapped in this way to continue sailing. The Gitana Team decided to change course and head initially for C…

par Gitana

The damage occurred and 5h30 this morning. Sailing in heavy seas and a strong wind (35 knots / Force 7), Gitana was facing up to heavy weather and had shortened sail with two reefs in the main and staysail up front. She checked in at 4h00 this morning with an instant speed of 11.2 knots as she was on a direct course to the Strait of Gibraltar. The Mediterranean lay ahead, just 50 miles east. Then for reasons which are as yet unknown, her dagger board broke on a level with the submerged part of the central hull. It cannot be due to wear and tear as the dagger board was new and was of the latest generation (digitally cut, carbon…)

As luck would have it…

It was impossible in such circumstances for Gitana to consider continuing her course with a broken dagger board, an indispensable appendage for making headway upwind. So, first of all, the crew decided to secure the largest part of the dagger board which was still in her casing, and then to head for Cadix (Spain). At 10h35, the trimaran skippered by Lionel Lemonchois was sailing along the breakwater of the Andalusian harbour and by 10h55 she had moored outside the harbour. However, upon the advice of the Challenge Mondial Assistance race directors, Gitana got underway several hours later bound for the marina in Puerto Sherry (bay of Cadix), better equipped to handle this type of boat. As luck would have it, Jean-Luc Nélias’s trimaran Belgacom was already in the marina, following her dismasting yesterday afternoon. A « sad » encounter, but the solidarity of seamen being what it is, Belgacom’s technical shore crew immediately offered to help the Gitana Team out, whilst awaiting the arrival of their own shore crew, expected to arrive around 20h00 this evening.

Gitana still in the race…

The Gitana Team has to be « examined » and a diagnosis of the scale of the damage will have to be made then envisage continuing the race with the 3 metres remaining of the 5 metres original length of the dagger board. One of the Gitana Team members will have to dive under the boat to see whether the breakage, the reasons for which have yet to be understood, has damaged the dagger board casing or not. It will take about 20 hours to carry out all the necessary checks and repairs, which in the best case scenario, would enable Gitana to set out to sea again tomorrow. The race will be on again.

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