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.

07.11.2003

With or without the wind….

Gitana headed west very early on and has continued to make good progress down the coast of Portugal. Subject to the same wind system as the neighbouring trimarans on the same latitude, the Lemonchois / Guessard team has gone from a tough south-south-easterly blow to a rather astonishing system.

par Gitana

Microscopic windless zones generated by a northerly moving low have given rise to asthmatic zones of wind, where winds of close of 50 knots kick in. This produces a situation whereby Gitana, Biscuits La Trinitaine, Sopra Group and Foncia are sailing in a direct line 50 miles from Sergio Tacchini at speeds of less than 10 knots whereas at 13h00 today Fauconnier / Foxall found themselves in steady winds of 40-45 knots with an average speed of more than 17 knots ? Difficult to explain… Gitana on the same latitude as Cape Finisterre (the north-western tip of Spain) with an average boat speed of 14.2 knots as at the 14h00 check-in today. With the wind playing hide and seek, producing a familiar accordion effect – and may hold a boat back, just as it may push her forward.

And what lies in store for tomorrow ?

All agree that the weather situation for tomorrow is unclear… A northerly moving system of low pressure for those to the west, a new front ahead for those to the east. Not easy to find your way through the tradewind highway. A simple question : will Gitana yield the benefits of her choice, like Alain Gautier and Ellen MacArthur on Foncia in the hours to come, a north-westerly wind, a saving grace ? Not likely as things stand for now, but who knows ? An ambiguous answer, if ever there was one, but that would enable them to let out all the canvas, hoist the gennaker and perhaps to gain ground on Belgacom, the fleet overall leader at the 14h00 check-in, currently 114 miles further east than Gitana. The race is far from over yet…

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