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.

19.03.2007

Off to a flyer.

par Gitana

After setting off as planned on Sunday 18 March in their attempt to beat the record for the Discovery Route between Cadiz and San Salvador (Bahamas), Gitana 13 and her crew have completed their first day’s racing. Twenty-four hours on from the start, Gitana 13 is ahead of schedule (calculated in relation to the first course mark in the Canaries) by roughly 40 miles. What’s more, her opening-day performance was superior to that of Playstation, the current record-holder with 9 days 13h 30′ 18”.

After a start marked by light air for the exit from the Bay of Cadiz, the Gitana 13 crew swiftly caught hold of the anticipated north-easterly flow to see the boat’s speed climb to 25 knots, complete with a first reef in the mainsail! The outcome of this first day is altogether satisfactory, with 520 miles covered on route to the Canary Isles, which the vessel should be running parallel to by early afternoon.

Currently, the catamaran is travelling at 30 knots in a 28-knot wind, small gennaker and Genoa staysail up. Oilskins are still de rigueur on the deck, although the temperature is rising steadily.

Weather: On Monday morning, Gitana 13 benefited from winds of 25 to 30 knots, with the result that she is already significantly ahead of schedule. Midday should see her draw alongside the Canaries, where the winds are likely to fall to 15-20 knots and then 10 knots. At the end of the day or possibly during the evening, Gitana 13 will leave the islands behind her.

Life on board: The crew has finally had its first real meal since Thursday’s evening’s departure from Trinité sur Mer, the 2 ½-hour stopover in Cadiz having been given over to anything but tourism. Courtesy of the Chalet du Mont d’Arbois restaurant, which has as usual provided the food on board, the sailors’ standard freeze-dried fare has been replaced by a succulent “Duck with endives”.

Finally, this start of the race seems an appropriate point at which to recall these few words penned by Christopher Columbus in the prologue of his log: “To successfully realize my plan, I am going to have to forget about sleep”. It is highly likely that this statement of intent will be echoed on Gitana 13 over the days to come!

Key facts:
Record to be beaten: Steve Fossett on Playstation in 2003 in 9 days 13 hours 30′ 18”Gitana 13’s start time: Sunday 18 March at 9h 7′ 08” UT

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