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.

23.08.2008

Gitana 13 on the shipping lanes.

Under gennaker in a more organised swell, the maxi-catamaran in the colours of the LCF Rothschild Group is continuing its east to west passage across the Indian Ocean. At an average of 27 knots for the past 24 hours, Gitana 13 is devouring the miles as it racks up over 650 mile days. It is an ideal scenario which nevertheless requires the utmost co…

par Gitana

The seas which have been manhandling the crew of Gitana 13 since its entry into the Indian Ocean some 48 hours ago, have now become more ordered: “It’s a lot less wet on deck! The wind backed (turned to a favourable direction for the boat to make headway) some time ago so we’ve been able to hoist the gennaker (large headsail) and we’re now accompanying the SE’ly swell. The seas are a lot better formed and more undulating than yesterday, which makes for more comfortable sailing”.

Aboard the 33 metre maxi-catamaran, the organisation is meticulously well oiled. The ten sailors are divided into three watches of three, who take it in turns on deck every three hours; a mix to which Dominic Vittet is added. The onboard navigator, in charge of the weather analysis and the smooth running of the boat, is effectively benefiting from a rather different status as he works outside the watch system. There is always one watch permanently on deck, the following watch are on standby ready to lend the crew up top a helping hand if need be, and the third watch are able to rest completely.
However, according to the conditions encountered by Lionel Lemonchois and his men, this organisation can be slightly modified to benefit performance or the recuperation of the crew. It is for this very reason that since Gitana 13’s entrance into the Indian Ocean, Dominic Vittet has been ensuring a certain rota system by integrating the standby watches: “We worked like this during the Route de l’Or too: twice a day, I take the place of a standby watch member. That enables the boys to benefit from twice the amount of sleep; the normal 3 hours being transformed into a total break of 6 hours” explained Dominic.

For the past 48 hours manoeuvres on deck have been rare, with the exception of hoisting the gennaker last night. However, far from twiddling their thumbs, the ten crew members have been making the most of the current situation to devote their time to the everyday maintenance of the maxi-catamaran : “We’re going right around the boat twice a day, most often at sunrise and at the end of the day. These regular checks allow us to survey the condition of the gear on a daily basis, which is essential in a record of this length” specified Olivier Wroczynski, before going on to say: “For my part I take care of anything related to power, water, electricity and the engine mechanics aboard. The start of the record called for considerable input on my part as the heat and humidity we experienced as we left Hong Kong didn’t facilitate the smooth running of all our machines. However, since the temperatures have dropped, everything has got back in order again.”

This morning, the maxi-catamaran equipped by Baron Benjamin de Rothschild was positioned 1 500 miles in longitude from Mauritius. For Lionel Lemonchois and his crew the goal remains unchanged: trying to benefit from the SE’ly tradewinds currently on zone, in order to continue making headway westwards and lining themselves up as best they can for rounding the Cape of Good Hope. From tomorrow though, three choices of route will be on offer to the crew of Gitana 13, so it will be high time to refine the strategy!

A few figures

Gitana 13 left Hong Kong on Thursday 14th August at 07h55’32” (UT)
Saturday 23rd August at 0745 UT, Gitana 13 was sailing at 16°33.23 S / 82°58.23 E

Watch No1: Lionel Lemonchois (Skipper / watch leader / helmsman) / Olivier Wroczynski (trimmer /head of computers and power) / David Boileau (Bowman / head of deck fittings)

Watch No.2: Ludovic Aglaor (watch leader / helmsman) / Laurent Mermod (trimmer) / Ronan Le Goff (Bowman)

Watch No.3: Pascal Blouin (Watch leader / helmsman) / Ronan Guérin (trimmer) / Léopold Lucet (No.1, head of supplies and doctor)

Outside the watch system: Dominic Vittet (navigator)

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