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Vincent Lauriot-Prévost: “This one-design formula brings many unknowns”

Published on 08/05/2019

The Solitaire has been raced on one-designs for 30 years, since the Half-Tonners were replaced. A radical new design, the Figaro Bénéteau 3 will now test the technical and racing qualities of the skippers much more. After having conquered the world with oceanic multihulls and revolutionising round-the-world racing in IMOCA monohulls, the design office of VPLP was selected to design and develop a new foil assisted boat for this fiftieth edition of The Solitaire URGO Le Figaro in 2019. This is the story.

This new one-design is radically different from its two predecessors!

To develop and select this new one-design initially there was a contest. In fact, at first we did not want to take part. But after due consideration we thought it was a good opportunity to strengthen our reputation and experience because our previous monohulls were always developed in partnership with other naval architects. Daniele Capua, who previously worked on the TP52s with Rolf Vrolijk, oversaw the initial study at VPLP. We were shortlisted with two other projects, that of Mer Forte and that of Sam Manuard who was working with Finot-Conq. We then turned to Yann Éliès and Pascal Bidégorry, two experienced Figarists who gave us good, precise feedback about the specifics of the Figaro Class.

It had to meet a tight specification?

It was required to fit a tight budget, a maximum length, a draft and a box-rule which took into account the new levels of ISO stability. Each team proposed different ideas. Mer Forte had a canting keel, but no foils; Manuard-Finot had water ballast and foils; we were the only ones to go with just foils. We therefore opted for a slim keel because the foils give grip against leeway.

And the foils can be adjusted when sailing?

There is “toe-in” (rake): the foil is at 45° and one can modify the longitudinal angulation between -3° and + 7°, to modify the angle of incidence. All Figarists focus on this angle: how much should you angle the foil and how to set it for performance. Theoretically, the angle is minimal (or even negative) in light winds which “cancels” the asymmetry of the foil. And as the breeze builds the skipper increases the angle of attack. In fact, the more there is an anti-leeway force on the foil, the greater the vertical component so the faster the boat goes, the greater the force of lift.

There were also structural requirements?

We knew that this concept could only work if there were well-defined, strictly controlled manufacturing processes, both in terms of materials and the working methodology. Without being as high-tech as the IMOCA monohull builders, you need to be much more stringent than for a “classic” construction of a cruising sailboat: the infusion is particularly controlled, the cutting of the foam panels is very tightly controlled, some materials have been specially made for the deck for example. And Bénéteau created a team of specialised laminators, just like JTA in Nantes thirty years ago!

The hull is typically of the modern form…

We have designed a hull which in essence is as powerful as a fully ballasted Figaro Bénéteau 2 with improved stability and better distribution of hull volume, but still with a comparable wetted surface. The length is very close to the maximum imposed by the specifications (9.80 m).

With a hull which for its size is quite large and powerful, it needed asymmetrical appendages that compensated for the leeway, hence the shape and configuration of the foils. In fact, they are not strictly foils since the Figaro Bénéteau is not going as fast as an IMOCA monohull. These appendages have a positive effect on the boat’s course and speed by reducing the sideways force and the angle of drift, whilst reducing the drag of the hull when it is in displacement mode. The first feedback from the sailors shows that the Figaro Bénéteau 3 works well upwind thanks to its asymmetrical boards (foils) which, the faster the design goes, gives a vertical lift of more than 400kg.

Stability is an essential factor?

The new boat is stiffer given the sail area compared to its predecessor which had ballast. Upwards of a certain speed, it is lighter and more powerful. In reaching conditions, the Figaro Bénéteau 3 is almost 800kg ‘lighter’ (i.e displacement and lift) on the water than the 2. It is true that in the light winds the new one-design has more drag in the stern sections but these are especially effective at inducing and maintaining planing. It is necessary to push the nose down and lift the stern as much as possible in these conditions…

Because it’s a one-design it works better?

The angle of heel so that the foil remains effective, 18° -20° upwind, is crucial and seems the optimum. The level of the “elbow” is key so that skipper will have to be careful not to “horizontalise” the foil and put the flat plane part through the waves. What we already know is that the Figaro Bénéteau 3 can reach up to 23 knots and more under gennaker at 120° to the wind.

It is a boat designed primarily for solo racing ...

Yes, ideally for three nights and four days at sea. But with performance and the stability it will be possible to do longer stages. The biggest differences compared to its predecessor are reaching where average speeds can vary by up to five knots. This could lead to big deltas, there could be very divergent courses, especially downwind.

So you have established polar charts?

We answer all the questions of the skippers but that is often more about feedback and chatting than the polar diagrams and numbers. For example, the angles are an important issue because by staying around TWA 130° you can hold the asymmetric spinnaker longer. But these are boats which are not so good for VMG (Velocity Make Good) downwind: you need to sail higher (at least 145°), and that opens the tactical options and spreads the field. And the foil allows consistent speeds and angles.

There is also an extra sail.

The gennaker can also be a Code 0. In fact, there is going to be a lot of sail development, both on the sizes and shapes of the two spinnakers and on the profiles of this new sail. The Figaro Bénéteau 3 is shorter, lighter and offers more options at all paces. The choice of a flat Code 0 will allow you to go fast in light airs upwind, the choice of a large gennaker allows great performance reaching in a breeze. Thus there are two schools in light and stronger winds.

The first feedback suggests the helm is very (too) light?

The idea was that the pilot has to work less hard and with a very light balanced rudder, so we aimed to not tire out the solo racers especially when reaching. But the downside of that is that you need to helm more. So you have to be very focused to get the best out of the boat. This should put more emphasis on the skills of the sailors. When setting up, it will probably be necessary to choose between adjusting the incidence of the foils or modifying the profile of the sails. Certainly, it will be necessary to take reefs in the mainsail sooner and more often and to achieve a better balance. There are many combinations (“toe-in” rudders, tension of the battens, incidence of the foil), which all in all equalises the game for newcomers and those coming back to the circuit.

In fact, there are many variables to manage with this new one-design.

This is a design with many unknowns to be learned, which will allow sailors to progress their skills and experience, making progress through the different races. The Figaro Bénéteau 3 has a steep, ongoing learning curve and it will probably be two full seasons before sailors are reaching near the top of the curve.

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