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.

19.05.2008

The noose is tightening.

Whilst the solo sailors in The Artemis Transat 2008 attack their 9th day at sea, over the next few hours the leading Imoca monohulls will pass under the 1,100 miles to go barrier, which separates them from the finish. Benefiting from a new zone of light winds, now in its wake, Gitana Eighty has closed on PRB, the latter still leading at the 1400 UT…

par Gitana

The sailors in the leading group have once again had to work their way through light airs in order to cross a ridge of high pressure from the Azores High and positioned over the route to the ice gate. However, after a morning coloured by light conditions, a welcome breeze returned to the race zone, as Gitana Eighty’s boat speed has born witness since the start of the afternoon: “We’ve just got going again! However, conditions are still quite incredible… It’s calm with a tempest of blue and 30°C on the deck of Gitana Eighty: you could also imagine you were in the Mediterranean. I’ve never experienced that in my previous four participations… I’ve never done this transatlantic race in swimming trunks before, particularly to the south of Newfoundland. All in all, our ice gate is appropriately named as, once you go through it, you’re certain not to see any!”

The ice gate was added to the course for safety reasons by the race organisation, so as to distance the sailors from the numerous icebergs indicated to the south of the banks of Newfoundland. As a reminder, it is situated at 40° North and between 47 and 50° West. In order to respect this course mark, the sailors may choose to leave it to their north or cross it at one given point at least.

However, the light conditions encountered by the top trio have been far from relaxing, as they’re already beginning to feel the effects of the next low, which is kicking up choppy seas: “The seas in which we’re currently sailing aren’t making our task any easier. This chaotic sea is testing for the gear, particularly given the slow speeds we’ve been racking up over the past few hours. It’s not easy for the helmsman either” confirmed the skipper of Gitana Eighty.

Still in 2nd place at the 1400 UT ranking, Loïck Peyron was nonetheless managing to snatch back some precious miles from the leader. Positioned 31 miles astern of PRB last night, Gitana Eighty had closed the deficit to 24 miles this morning and just 15 miles midway through this afternoon: “this light weather is slightly inconvenient, but it’s important for tightening the noose on the leader!” confided the sailor from La Baule on France’s Atlantic coast at the start of the afternoon.

Now on port tack bound for the ice gate, the fleet is preparing for the wind to freshen this evening. Indeed, the protagonists in The Artemis Transat 2008 will have to weather another front with gusts of over 35 knots expected.

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