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.

14.05.2008

Ridge of high pressure straight ahead.

par Gitana

The thirteen solo sailors in The Artemis Transat 2008 are continuing their sprint across the North Atlantic. However, after over 3 days at sea and 900 miles under their belts, the pace is set to slow as the fleet have to negotiate a barometric col over the coming hours. This rather atypical situation is raising lots of questions aboard the fleet of monohulls. At the helm of Gitana Eighty, Loïck Peyron has climbed up to 4th position this Wednesday, whilst Michel Desjoyeaux has taken back the provisional reins of the race.

After three days and a few hours of racing, the top five 60 footers in this 2008 transatlantic race are squeezed into less than thirteen miles and aren’t giving an inch. Amongst those skippers favouring the north – slightly above the great circle route – are Michel Desjoyeaux and Yann Eliès, whilst Sébastien Josse and Vincent Riou are positioned further south. Meantime Loïck Peyron has opted to go it alone in the middle of the fleet; this positioning enabling him to be one of the fastest of the leading group at the 1400 UT ranking.

Renowned for the large Atlantic lows which sweep across the fleet during the event, The Artemis Transat is this year showing another side to its nature, as the solo sailors do battle with irregular, easing winds in particular: “It’s quite amazing how incredibly localised the conditions are that we’re encountering. Within the space of just a few miles, the wind variations are very different, which largely explain the speed differentials of the boats” explained Loïck Peyron, before going on to say: “We should still be downwind for another 24 hours but we’re going to have to traverse a light depression zone. It’s not easy to find the right place to slip along there!” This tricky passage, which will bring about a considerable reduction in pace over the coming hours is on everyone’s minds, and the subject fuelled a number of discussions at midday. “One thing for sure at the moment is that the situation ahead is complicated…” A real meteorological brain-teaser in view then, which inspired this morning’s pearl of wisdom from the skipper of Gitana Eighty: “It’s going to be a casino! There are little blue disks (synonymous with a total lack of wind) pretty much everywhere… we’re going to have to be on top of our game and be very responsive so as not to get caught by the calms” detailed the sailor from La Baule.

As the fleet wait for the wind to drop out, Loïck Peyron has been benefiting from more ordered seas and a suitable air flow to recharge the batteries and rack up a few precious minutes of sleep. “I am using my automatic pilot a lot, which, even though I’m not sleeping much, does enable me to get a fair amount of rest.” Lucidity and energy are both going to be useful over the next 48 hours to better negotiate the first really tricky passage of The Artemis Transat 2008.

The Ice Gate
For safety reasons and given the numerous icebergs which have been pinpointed around and to the south of Newfoundland, the organisation has opted to add a gate to the course, referred to as an ice gate. Situated a long way south, it lies between 40° north and 47.50° west. The solo sailors will have to pass through this gate via at least one point.
Given that the great circle route (the direct course) takes the sailors level with the banks of Newfoundland, just off Cape Race, the position of this gate is very important in terms of the routing strategy worked out by the solo sailors.

Ranking of the top five Imocas at 1400 UT
1. Foncia (Michel Desjoyeaux) 2,053 miles from the finish
2. Generali (Yann Eliès) 7.9 miles from the leader
3. BT (Sébastien Josse) 9.4 miles back
4. Gitana Eighty (Loïck Peyron) 12 miles back
5. PRB (Vincent Riou) 12.7 miles back
(…)

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