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.

06.06.2004

Going nowhere fast.

Fred Le Peutrec did not have much luck last night. The third low was supposed to move north-east slowed a great deal and is right overhead Gitana 11.

par Gitana

Fred Le Peutrec did not have much luck last night. The third low was supposed to move north-east slowed a great deal and is right overhead Gitana 11.

Fred Le Peutrec is going to have to be patient before his trimaran can spread her wings and fly again. The eye of the depression is almost bang smack above Gitana 11 and is moving very slowly. Fred has no choice but to sit back and wait for the wind to change to a north-westerly direction. This should be happening very shortly – just a matter of hours. A stroke of bad luck which has done nothing to dampen the skipper’s determination. The soloist still hopes to manage to join as he is far from being alone in this situation – and half the race remains to be run. Bearing in mind that a high pressure bubble will be settling over the coast of America this evening, the fleet leaders should also be slowing down. The miles lost last night should be made up for on Monday morning.

« I’m up on deck fighting like a madman to keep the boat moving. I’m in a dead calm and have barely budged an inch since yesterday evening …boat speed is one to one and a half knots, the wind direction is very unsteady. A pity really as I was hanging on to the pack. It’s going to be tough catching up now as they’ve headed west. We hadn’t expected me to fall into this wind hole. I have to wait for the wind to come to me as at 0.7 knots, I can’t go and fetch the wind ! I was determined not to get shaken off and I’m annoyed that it has happened ! I hope things are going to start looking up soon as the outlook is not clearly established for the finish yet.

Otherwise, after what was a physical race to start with, has now turned into a very, very calm race indeed. A race full of contrasts ! After a heavy-going start, we’ve got to concentrate on the banks of Newfoundland… I’m in good shape physically and mentally. »

Fleet leader Michel Desjoyeaux on Géant is expected into Boston on Wednesday or Thursday. But before hitting the jackpot, he has to keep an eagle eye out for the many booby traps which lie ahead. Fog, fishing vessels, oil platforms, drift nets and whales, not to mention a bubble of high pressure which could re-shuffle the pack, for the first three boats at any rate, which are within 130 miles of one another.

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