Diable est-il lui ?

As promised, here is a further look into Yves Parlier's wild 60 ft. catamaran from Jocelyn Bleriot, Course Au Large magazine. Enjoy.

First of all, the boat is called "Hydraplaneur", which is a neologism invented by the skipper (it can translate into "water glider").

She's been built out of carbon and Nomex honeycomb core, her structure is a complex one with many compartments. In case a breakage occurs, it will not spread to the whole platform. An interesting feature: the boat's been fitted with strain sensors using optical fibre technology. When the structure twists and is deformed under the efforts, the fibres vary in length, and their variation is measurable so the technical crew can have an idea of the degree of flex the hulls or the mast have to cope with. Later on, these strain values will be available "live" via the onboard computer. It will be like the red zone on the rev counter of a race car : the navigator will just have to shout "too much tension on the forestays" to the guys up on deck. Way better than seeing the mast(s) come down. Basically, on today's Open 60 tris, you never know the accurate level of efforts - until the boat breaks.
What Nigel Irens (total genius) usually refers to as "Scale 1 crash test - you know it was too much when it breaks". A certain idea of empiricism.

Sail inventory :
the hydraplaneur carries 2 mains, and two types of gennakers. The big one can be used up to 25-30 knots of breeze. The small one I have no idea - but all I can say is that is has a better shape than the big one. Beam reaching with the small gennaker is the ship's favourite angle (that figures). 2 small jibs (ORC type) complete the inventory. Note that foresails are hoisted to leeward (otherwise the boat would bear away too much). The hydraplaneur is quite good upwind, she's got a really good angle but is not impressively fast close hauled (I saw 15 knots with 14-15 knots of breeze).

Cockpits:
Each one fitted with three winches, two of them linked to a coffee grinder. The two travellers and one mainsheet can thus be controlled simultaneously. When the gennaker is up, you either free one of the winches or send a guy to the leeward cockpit. The gennaker sheet comes back via a block fitted onto the extremity of the mainsheet traveller, sticking out on each side of the boat. (see rendering - boat seen from behind)

During preliminary studies, the hulls were tank tested and confronted with the classic shape of an Open 60 tri's float. Tests simulating 4 metres waves (typical north Atlantic spectrum) were also carried out successfully.

Below is a pic of the 25' prototype, on which you clearly see the step in the hull. This one reached more than 28 knots (not bad for a 25 footer).

What more? Well, the interior is very very uncomfortable - just can't stand up. The bunks are coffin-like, and the chart table is narrow. Good luck for fully crewed events guys !

For the moment, Yves and the guys (for the anecdote, Yannick Bestaven, who won the 2001 Mini Transat, is now part of the crew) don't push the boat too hard and want to learn gradually. The rudder blades are T foils, the horizontal part is designed to have a variable incidence angle, thus allowing to alter the horizontal trim so the cat' can take off sooner). But for the time being, they remain in one position - better learn to handle the double rig first. The daggerboards generate a slight upward thrust.
Perhaps the thing which is most noticeable is that the boat speed does not quite pick up smoothly : between 15 to 20 knots, the hulls generate waves and move a lot of water, but after that, the drag decreases rapidly (the steps come in action, just like on motor boats, which generally are sluggish at low speeds), and the cat accelerates in a snap.

She tacks pretty easily too, since the bows are out of the water. Just ease off the windward mainsheet first, the boat luffs then push the helm. Once tacked, trim the windward main first (the boat bears away and picks up speed) then the leeward main to catch the proper course.

Aquitaine Design Team (the brains behind the beast) : Guillaume Verdier, Loic Goepfert, Romaric Neyhousser, Grégoire Durousseau. (All in their late 20s / early 30s)

Specs:
LOA : 60ft
Beam: 15 metres (50 ft)
Draft: 3,8 m
Sail area upwind : 240 sq.m.
Sail area downwind : 390 sq.m.