Vendée Globe

For this sixth edition of the Vendée Globe, designers have moved up yet another level in terms of hull designs, ease of handling, deck layouts, the size of deck fittings, fine tuning the rig, developing appendages, scaling down internal fittings… Here are some of the major developments in 2008:

With eighteen prototypes built specially for this sixth edition of the non-stop solo round the world race, in addition to two others launched in 2005 (Maisonneuve and Pakea Bizkaia) and three boats from 2003 which have been upgraded (Cheminées Poujoulat, VM Matériaux and Veolia Environnement), three-quarters of the fleet is more or less made up of new boats!

As design changes incorporate every aspect from navigation to deck fittings, rigs, hulls and appendages, from sails to computers, the leaps forward have been exceptional. All the designers agree that the potential of this new generation of IMOCA monohulls has increased by between ten and fifteen percent. Few other mechanical sports can compare to this phenomenon, largely due to research carried out for the America's Cup, the Volvo Ocean Race, the Mini Transats, and on maxi-yachts… Here are some of the features of this marine revolution, driven by sailors always on the lookout for improvements in performance.
 
Sails: The speed of boats has increased considerably — especially downwind, with sails becoming flatter.  Solo sailors prefer gennakers instead of spinnakers, which are very difficult to handle in strong winds (above twenty knots). There are ever-increasing similarities with multihull sailing. Sail areas upwind have increased, particularly with the foresails, with today's staysails resembling yesterday's jibs… As for the mainsails, they all have a square top, with a shape carrying more sail area higher up, thanks to a huge batten (more than three metres in length) at the head of the mast.
Rigs: Masts have been growing increasingly taller and some Open 60s like Bahrain Team Pindar have a clearance of 32 metres (for a hull measuring 18.24m). The weight of the carbon tube has become lighter and lighter (420 kg for a classical mast with the shrouds) but skippers remain divided when having to choose between the usual oval shape and a wing mast. The latter is aerodynamically more efficient, but requires larger and larger outriggers (deck spreaders) to hold up these masts. Chord (width) has also been increasing, with a convex section on the luff for greater efficiency (Artemis). Genoas are no longer always hoisted and furled, to limit the weight aloft hook systems are being used instead.
Hulls: Evident since 2004 on boats designed by Marc Lombard (VM Matériaux, Veolia Environnement), chines have today become a common feature on designs from VPLP-Verdier (Safran, Groupe Bel), Finot-Conq (DCNS, Hugo Boss, Generali, Brit Air), Kouyoumdjian (Bahrain Team Pindar) and Rogers (Artemis), as well as on the Farr designs (Delta Dore, BT, Foncia, PRB, Gitana Eigthy, Paprec-Virbac). This ridge on the side, particularly at the stern, is aimed at allowing more sail to be carried in strong winds without increasing the beam at deck level and therefore the weight of the hull. They also ensure the best heel angle (20°) allowing water to flow in a V-shape when heading upwind.
Devices: To reduce the risk of pitching the bow into waves, two systems have been put in place in this race. The trim tab on Paprec-Virbac and Gitana Eighty corresponds to the type of flap more often seen on the transom of fast motorboats: when raised, it modifies the longitudinal trim of the boat, which raises the bow up (downwind); when lowered, it extends the waterline length of the boat (upwind).  This year some of the fleet also feature strakes, which are projections added to the side between the bow and the foot of the mast. This raised section takes the strain off the bow when it digs in, while offering additional help to stay on course.
Appendages: The most unusually-shaped daggerboards are found on Safran — the design team of Marc van Peteghem and Vincent Lauriot-Prévost, in association with Guillaume Verdier, have been inspired by the curved foils on ocean racing trimarans. The aim is to reduce the space taken up on deck when the daggerboards are raised, and give added lift. As for the keel, the use of nuclear submarine steel has allowed DNCS to reduce the thickness — giving less drag for almost the same weight as a carbon blade. Almost all of the rudders can be raised using extremely sophisticated systems to alert the skipper in case of collision with an OFNI (magnetic alarm).
Cockpit: IMOCA monohull cockpits are particularly wet and unpleasant places to be once the wind exceeds twenty knots, thanks to the spray and tons of water crashing over the deck. Several of the fleet are now fitted with a sliding cuddy protection to enable the skipper to carry out manoeuvres under shelter, even if the visibility over the bow is nil. Other skippers have gone for plexiglass domes to allow them to remain at the helm without getting wet. Two Finot-Conq designs have come up with an original solution (DCNS, Hugo Boss), with all of the ropes coming down from the foot of the mast to the middle between two companionways, protected from the worst of the fire-hose effect.
Energy: A lot of evolution has taken place linked to research into alternative energy. The aim is to reduce the amount of heavy and polluting fuel carried by the 60s. Wind turbines are finding favour, as they become more and more efficient when the wind is above twenty knots, which is almost always the case in the Southern Oceans. Raphaël Dinelli has come up with a large turbine that is still light thanks to its carbon blades, but has a unique vertical rotation axis instead of a horizontal one. There are also solar panels onboard some boats, with the skipper of Fondation Ocean Vital developing highly efficient photoelectric cells with an extremely thin, yet resistant protective film. Hydro generators can be found too on boats like Aquarelle.com: the submerged blade offers additional energy from fifteen knots of boat speed without any slowing effect due to drag.
Interiors: The days of cosy interior layouts with comfortable furniture, bunks than can be angled, and gimbled kitchens is over! In this age the skippers carry the bare minimum, resulting in a surprising emptiness down below. When it comes to decorating, there are two opposing schools of thought: some favour a light, airy space, with everything painted white with plexi panels to allow the light to flood in, while others favour a restful — and weight-saving — approach of leaving the black carbon exposed. As far as furniture is concerned, we now see foam seats which mould to the shape of the body (Foncia), and rotating desks (Gitana Eighty, Paprec-Virbac) while others have a chart table, seat and nav desk that can slide out or be pushed to one side.

DBo
 

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