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.

20.03.2007

After the Canaries.

par Gitana

Still on course for her attempt at the record in the Discovery Route between Cadiz and San Salvador (Bahamas), Gitana 13, having left Cadiz on Sunday 18 March at 9h07mn08s UT, passed the Canaries in the early hours of this Tuesday 20 March. And it was a case of relief all round, as in the archipelago, the wind was variable and low and consequently difficult to harness. By the end of the night, it had risen back to 15 knots and should maintain this force throughout the day, thereby allowing Gitana 13 to extricate herself from the archipelago.

It was amid very poor visibility and in full sails that, just before sunset, Gitana 13 drew alongside the shores of Gran Canaria, to the starboard side.

After a few gybes between the islands and a proper cold sweat when the crew almost got bogged down in the windless zone created by the island, life regained its usual rhythm on board for the 12-man team. A regular westerly flow of 10 knots on a fine sea offered Gitana 13 her first real moment’s respite since her departure from Trinité sur Mer last Thursday!

At 11:30 UT today, she was sailing with the mainsail and small gennaker. The expected northerly flow was settling in and over the following fifty miles or so, the boat should have finally escaped the influence of the Canaries.

Coming out of this difficult night, the team are slightly off the pace in relation to Steve Fossett’s record, but the conditions to come seem to offer some cause for optimism, judging by the good mood of Lionel Lemonchois on the phone this morning: “We had a bit of a rough night due to a difficult passage of the Canaries that resulted in us losing a bit of ground. But in the hours to come, the situation should settle down and allow us to get back up to normal speeds for the boat. It’s still doable… We’ve not had any technical problems to speak of since the start, everything’s been going well. The boat may be 8 years old, but the technical improvements we made over the winter have all borne fruit and the boat is a lot better. On board, we are organised into 3 watches of 4 crewmen, which revolve every three hours: 1 on the deck, 1 team on standby, and the other sleeping. In this way, all eight of us can be on deck if need be. Over the coming days, Dominic Vittet, the navigator on board, and Sylvain Mondon (Meteo France), are promising us a nice anticyclone with wind, so morale is good and the record is still within our grasp!”

On Christopher Columbus: In an era when technology constitutes a precious aid for sport, one that is essential when it comes to setting and breaking a record, it’s worth recalling the subterfuge to which Christopher Columbus had to resort. To prevent his companions being alarmed by the distance already travelled, the navigator took care, when keeping his log, “to mark less than the real distance so that, if the voyage was long, my people would not become terror-stricken.”

The three watches on Gitana 13:
Lionel Lemonchois (Watch leader) – Nicolas Raynaud – Jean-Baptiste Epron – François Denis
Loïck Peyron (Watch leader) – Dominic Vittet – Leopold Lucet – Antoine Mermod
Loïk Gallon (Watch leader) – Jean-Baptiste Le Vaillant – David Boileau – Cyril Dardashti

Key stats: Record to be beaten: Steve Fossett on Playstation in 2003 in 9 days 13 hours 30mn 18s (source WSSRC)
Number of miles to be covered: 3,901 miles
Gitana 13’s start: Sunday 18 March 2007 at 9h 7mn 08s UT

Update at 14:20 UT:
Latitude: 26°07,92 N
Longitude: 18°33,74 W
Instantaneous speed: 14.3 knots
Course: 282°
Distance covered since start: 867 miles
Distance to finish: 3034 miles
Average speed since start: 16.29 knots

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