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.

20.05.2008

Gitana Eighty keeps the pressure on the leader.

par Gitana

Boston and the finish line are looming up fast this afternoon, less than 900 miles ahead of the top duo, still comprised of Loïck Peyron and Vincent Riou. However, the weather situation over the coming days promises to be particularly complicated, and certainly won’t make life any easier for the sailors. Between the passages of fronts and zones of light winds, the ten solo sailors still in the running following the retirement of Michel Desjoyeaux, Sébastien Josse and most recently Unaï Basurko, will need to be sailing at 100% of their capacity and their lucidity in order to cover this final third of the course.

The ice gate was no trifling matter for the leaders in The Artemis Transat 2008. As Loïck Peyron mentioned yesterday, the top trio made a brief touchdown at the latitude of 40° north, prior to heading to the NW. The skipper of Gitana Eighty commented on this tricky passage: “It would’ve been perfect give or take half a mile! Just a few boat lengths from the gate, the wind began to ease and I hoisted the genoa to make headway. It proved to be a mistake as the wind kicked back in as it headed, and by the time I’d furled in the genoa I had to put in a tack to cross the gate. In short, not easy and the lost ground could have been avoided.”

Once the ice gate was behind him, the sailor from La Baule was able to reap the benefits of a wet but pleasant night: “We finally had a slightly feisty night… with the spray dumping onto the deck at time and peaks of speed at 18 knots. Above all though, the seas were relatively flat and favourable for sleeping!” This rest is essential after 9 days of racing and too many manœuvres to count, as the fatigue is beginning to weigh on the skippers. All too familiar with this scenario, the skipper of Gitana Eighty doesn’t give a second thought to making the most of any opportunity that presents itself in order to recuperate.

In the Imoca monohull fleet, the alternating conditions are all par for the course on the programme of events for the solo sailors. Having to reconcile the passages of lows and zones of transition, where the wind is somewhat lacking, Loïck Peyron and his rivals are making constant manoeuvres and adjusting their sail wardrobe in order to conserve the best heading/speed compromise. “This evening another light zone awaits us and with the wind turning every which way, things are likely to be fairly complicated. There’s going to be a lot of work on deck with the sail changes and tacks. Despite all that it’s going to interesting!” The appeal lies in the fact that all these transition zones are tricky passages which are favourable for making gains on rivals, or indeed losing them: “these periods are very important and require the greatest of attention from us as it’s during these spells that we can make up ground as well as lose it!” Loïck Peyron recalled.

At the 1400 UT position report, Gitana Eighty was hot on the heels of PRB and had reduced its deficit still further; Vincent Riou had a lead of just 12.6 miles: “I have a serious customer ahead of me, who is really sailing cleanly. However there are numerous transitions still awaiting us – at least five before the finish – which will give us something to play with!” Sailing on port tack to windward of the leader, the most recent of the Gitana fleet is on the attack; a pressure that the double winner of the event fully intends to keep up for the last third of the course.

Ranking at 1400 UT on 20th May
1. PRB (Vincent Riou) 840.5 miles from the finish
2. Gitana Eighty (Loïck Peyron) 12.6 miles from 1st place
3. Brit Air (Armel Le Cleac’h) 59.8 miles
4. Generali (Yann Eliès) 136.6 miles
5. Safran (Marc Guillemot) 323.4 miles
(…)

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