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.

31.08.2003

A frustrating Grand Prix de Fécamp !.

Very much at ease on each of the starts, even rounding the offset mark of the inshore course in second position, Gitana was distanced on a regular basis for lack of adequate sails to keep the others at bay, her Grand Prix mainsail having torn during the Thursday training session. The boat's weight has its role to play in this type of performance.

par Gitana

Very much at ease on each of the starts, even rounding the offset mark of the inshore course in second position, Gitana was distanced on a regular basis for lack of adequate sails to keep the others at bay, her Grand Prix mainsail having torn during the Thursday training session. The boat’s weight has its role to play in this type of performance.

It seems pretty clear now that Gitana’s lack of speed is essentially due to her displacement, much greater than the other multihulls on the ORMA 2003 circuit. A two-stage weight loss programme was therefore been planned in the beginning of July to optmise the boat.

The first part of this programme was completed prior to the Grand Prix de Fécamp. The next stage will get underway shortly afterwards, with the two-handed Transat Jacques Vabre in mind, a race which starts off Le Havre on 2nd November.

Fired up with the perspective of further improvements, the crew approached the last Grand Prix of the season with a fresh dose of confidence. Unfortunately, right from the word go, at the training session on Thursday morning, Gitana tore her mainsail during a gybe. No choice for the Gitana Team but to face up to her opponentts with the mainsail used for delivery passages on the difficult waters off Fécamp.

Gitana therefore ranks 8th out of 11 boats entered in the last Grand Prix of the season. Three boats withdrew due to gear failure – Foncia and Belgacom called it day on Friday due to mast problems and Bayer after having been run into by another competitor at the start of Saturday’s inshore course.

Objective transat

The final analysis of this event never the less remains positive. In spite of the boat’s lack of speed, he crew remains motivated, nd, if proof were needed, this was demonstrated by their aggressiveness on the starting lines. As for Lionel Lemonchois and Marc Guessard who will be sailing Gitana together in the Transat Jacques Vabre, they have continued to acquire new data to assist them in getting the best out of this complex machine, which is rather tricky to perfect.

That said, during the qualifying passage undertaken in tough conditions in part, Gitana has proved that she is a healthy boat. Lionel Lemonchois : « in 25/30 knots downwind, and rough seas in the Bay of Biscay, we made an average speed of almost 25 knots over an 8 hour period in excellent conditions of reliability and manoeuvrability. Gitana doesn’t nose dive because she has banana-shaped floats. I’m confident… ». Further in a two-handed race, « …a speed and course-holding handicap is much less detrimental than in a Grand Prix event… », affirm Lionel and Marc in unison.

A new set of sails specially designed for this event should make it posible for them to come clsoer to the level of the other competitors in the ORMA 60-foot multihull circuit. Gitana still has to go through the second four-week stage of her weight-loss programme at the start of next week in the boat’s base at the Multipole 56 in La Trinité sur Mer.

More information :
www.multis-online.com

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