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.

25.11.2019

Traffic separation at Saint Helena.

par Gitana

The newly-formed Brest Atlantiques trio is continuing its slow climb up towards the equator from Cape Town. Still leading the way, the Maxi Edmond de Rothschild boasts a 244-mile lead over Actual Leader to her East and a 650-mile lead over Macif, which yesterday decided to try its luck to the West. Though the weather scenario for this return to the northern hemisphere is not the easiest of passages to negotiate for the crews, who are having to get the best out of a breeze that is as light as it is unstable, the resulting game of strategy is further spicing up the race after twenty days at sea.

All roads lead to the equator

Late yesterday, Franck Cammas was explaining the latest meteorological and strategic situation in front of Yann Riou’s camera as the crew embarks on this second section of the climb up the South Atlantic. “We saw on the rankings that Macif had gybed twice with a median course to the south-west. Gybing in this spot clearly signified that it was taking a completely different option to the one that everyone had appeared to be on for several days… namely the one we’re on and which Actual is also in the process of following.” The skipper’s suppositions have since been confirmed.

“There’s a front bordering our zone (note: ‘bordering our zone’ is just a figure of speech since it is 1,000 miles from the position of the Maxi Edmond de Rothschild) and once that rolls through we will have a SSW’ly breeze off the back of it. For sure, one of the models shows the optimum course as passing through this front and hence really heading a long way off the direct course we’re currently on. It’s going to have its work cut out on that course as it’s far from easy,” assured the skipper of Edmond de Rothschild. “It makes no difference though to us. We’re not in the same place as him, at the same time, so our optimum course is different to his.”

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Biding one’s time

The South Atlantic and the Saint Helena High certainly hasn’t let the sailors competing in this 1^st edition of the Brest Atlantiques off lightly! Indeed, during the descent between Rio and Cape Town, the northerly rounding of a fine depression and the positioning of the high pressure a long way south had already made life difficult for them. As such, the fleet had hoped they’d already paid their dues… However, this was without taking into account the scenario put forward by the Saint Helena High – yet again! – on the homeward passage: “It’s not quick! The centre of the anticyclone is currently situated 660 miles to the North-West of Cape Town, so it’s not in its normal position and is not very solid at 1021 hPa. Towards Brazil, there’s a low-pressure front that has formed and is dropping towards the forties and South Africa. The combination of these two phenomena is causing a complete rupture of the SE’ly trade winds. This in turn is making our progress towards the equator quite long! We’re set to get back into the northern hemisphere on Wednesday night through into Thursday”, explained Marcel van Triest, router for Gitana Team.

It is possible to helm one of the fastest boats on the planet, but when the weather conditions are not lined up to enable a quick passage towards the goal, there’s no other option than to bide your time and above all make the most of any opportunities offered up by the variations in the breeze throughout the day. This is a notion that Franck Cammas never forgets: “Part of the appeal of offshore racing is that it’s not just a drag race… even if going quick often helps. Offshore racing is primarily all about weather and strategy. There are a lot more gains to be made thanks to weather choices. It’s like a game of chess with things you don’t always control. Even though there’s a lot of theory involved, in practice it’s about sensitivity and experience and a human touch, all of which colour the strategic choices.”

Ranking on 25 November 2019 at 15:00 UTC

1. MAXI EDMOND DE ROTHSCHILD (Franck Cammas / Charles Caudrelier / Yann Riou) – distance to the goal: 3,714 miles – average speed over the past 30 mins: 16.1 knots

2. ACTUAL LEADER (Yves Le Blevec / Alex Pella / Ronan Gladu) – 244.8 miles behind the leader – average speed over the past 30 mins: 15.4 knots

3.MACIF (François Gabart / Gwenolé Gahinet / Jérémie Eloy) – 650.5 miles behind the leader – average speed over the past 30 mins: 17 knots

RETIREMENT – SODEBO ULTIM 3 (Thomas Coville / Jean-Luc Nelias / Martin Keruzoré)

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