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.

25.02.2008

A question of time.

par Gitana

Today it is our 40th day of sailing on the big blue. Suffice to say that for the majority of us, seven out of ten to be precise, we have largely exceeded our previous time spent at sea. It is rare to tackle courses as long as this, the sole exception being that of the non-stop round the world voyages. Lionel Lemonchois, Ludovic Aglaor and Florent Chastel were together aboard Orange 2 during the Jules Verne Trophy for just over 50 days. However, the prize for the ‘longest time at sea’ evidently goes to our skipper. On this same Route de l’Or in 1994, on the monohull skippered by Isabelle Autissier, Lionel snatched the record in a time of 62d 5h 55′!

It remains that time at sea is a rather abstract concept. Six days ago, we were passing the equator, six days that we haven’t noticed go by. This wasn’t the case during the climb downwind along the Easter Island high. Indeed there, whilst the sailing conditions were ‘idyllic’, the days appeared to be more drawn out. This was doubtless due to our inactivity because since we’ve been on the move again, like this weekend with a fine upwind navigation under skies of an incredible pureness, the watches have been absolutely flying by.

This 40th day is also the opportunity to celebrate our symbolic passage under the barrier of 1,000 miles remaining until we cross the finish line situated, not under the Golden Gate Bridge, but at the foot of the no less renowned prison of Alcatraz. We hope to reach this islet in the middle of San Francisco Bay, a site now playing host to tourist visits, on Thursday 28th February. With 700 miles covered during the past 48 hours and similar sailing conditions forecast, we may well get there a little earlier. Here we have this N’ly wind of around fifteen knots then, forbidding a direct course. To make our destination, we’re going to have to put in some tacks, thus extending our course. We’ll do everything we can to get there as soon as possible, but that won’t prevent us from making the most of the final days of what is a beautiful, long voyage.

Until tomorrow
Nicolas Raynaud

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