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.

16.11.2007

The perils of the doldrums….

Having been in second position until Wednesday evening and chasing an Ecover who had built up a solid lead, the Loïck Peyron-skippered Gitana Eighty made a bold choice for the crossing of the invariably treacherous doldrums. At 16:00 today, as they await their emergence, hopefully in a matter of hours, from the clutches of this infamous zone, the b…

par Gitana

Located just to the north of the geographical equator, the doldrums are a kind of “meteorological equator” that represents the critical point of this Transat Jacques Vabre: all the skippers know it, whether they are the helm of a multihull or a monohull. Formed by highly complex, violent and unpredictable weather systems, the secret to their successful negotiation is to avoid the windless zones by surfing between the squalls order to emerge with the best possible angle for exploitation of the trade winds, which should propel them smoothly to the finish line.

In an echo of the strategy adopted by Gitana 11 a few days ago, Loïck Peyron chose to pass through the eastern section, the shortest route provided sufficient wind is present. But unfortunately, the doldrums closed in around the bows of the blue monohull, which explains the vessel’s 9th position at 16:00 French time on Friday. As for the boats that opted for the more western route, they seem to have found the most favourable path and are starting to increase the gap. As usual, the notorious doldrums have reshuffled the pack of a fleet now spearheaded by Michel Desjoyeaux. Currently sailing large gennaker and mainsail up, Gitana Eighty hopes to emerge from this difficult passage in the next few hours and is not letting her head droop. After all, the race is not over yet.

Review of the last 24 hours
15/11/2007 – 18:11 – Loïck Peyron, Gitana Eighty: extract from the midday radio chat
”It’s anything but quick. We’re in the middle of large squalls, classic doldrums really. Talk about cats and dogs! We’ve filled up a dozen litre water bottles. And this is real heavy tropical rain. There are quite strong storms, lightning, and raindrops the size of golf balls! What a lark! We hope to be out of it soon, but for the moment, the wind is highly variable and we’re stringing together gybes, trying to tap into the slightest gust of air. The squalls are impressive, but there’s only 15 to 20 knots of wind so they’re not that dramatic. For the moment, our choice of strategy doesn’t look particularly inspired, but we’ll see. It’s not over yet!”

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