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.

05.06.2004

Back into shape.

For the past 48 hours, the eleven single-handed multihull skippers have had a brush with a hefty low which has given rise to winds of more than 50 knots (force 11) and even the monohulls 500 miles further east have suffered. Virbac was capsized by rogue wave and has dis-masted. Fred Le Peutrec has made the most of this weather check to get some res…

par Gitana

« Not a lot happening at the moment ( 9h00 Saturday morning). I’m going to go and get a quick hour’s sleep in before the new front kicks in around midday. Winds with squalls of more than 30 knots are forecast … I’ve still got a 15-knot westerly wind which is gently veering SW. I’ll soon be changing tack. I’m quite tired in fact as apart from the fact that my Solent jib exploded on Thursday night, and my narrowly missing turning turtle as a result, a whole series of minor hitches have piled up. The sea was really wild and a 45-knot wind blowing (with gusts of up to 52 knots !) when the Solent jib formed a pocket and started flapping like a mad thing…
After that, a reefing pendant broke (a line which holds the main sail to the clew). Everything got wound up in the lazy jacks (lines which relieve the boom) ! It was a mess, not to mention all sorts of odds and sods such as blocks and lines which have given up the ghost… What’s more it’s freezing cold. It’s rather stressful and it was impossible to sleep. So this morning I’m really tired. But I am never the less, I’m really pleased to have come through the worst of the low and still be in the race, even if the absence of the Solent jib handicaps me when the wind drops. »

At Gitana Team’s base in La Trinité, the shore crew is hard at it and Marc Guessard has handed over to Yann Guichard to provide Fred with weather information. « We’re on stand-by round the clock to answer questions which Fred asks at sea. As a rule, Gitana 11 calls us every three hours to say how things are going. Not only do we supply info along with Sylvain Mondon of Météo France, comprising an analysis and summary of the outlook for the hours ahead, but also psychological support. This morning, Fred is really tired and we advised him to get some sleep straight away as three hours form now a front will be passing overhead, giving rise to winds of 25 knots and squalls with gusts of up to 35 knots. The thing to remember when sailing solo is that the slightest hitch takes on enormous proportions and often it’s just one thing after another. It’s essential to rests and clear one’s head. »

On Saturday morning, Gitana 11 had her unreefed main up and storm sail in a 15-knot head wind. Fred was getting ready to tackle the third low since the start form Plymouth on Monday and should be reaching the banks of Newfoundland this evening. At last the skippers have agreed to respect a « virtual point » 47°N and 47°W so as to avoid entering into the zone where icebergs appear frequently, east of Newfoundland.

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