The latest Alinghi unveiled at last

On Friday the Daily Sail got to see the new monster catamaran in her tent at Villeneuve

Finally the months of conjecture are mostly over. Yesterday we made it up to Villeneuve, Switzerland to get the long awaited first glimpse of Alinghi’s radical new AC33 defender.

In very general terms the boat we saw is what we expected - a scaled-up D35. But while the D35 tries to be effectively a trimaran without a centre hull, the new Alinghi goes substantially further down this concept route with a catamaran that is 90ft long, but we suspect is 70-80ft wide (our colleagues think she is more or less square - we are uncertain having only had to opportunity to get a perspective from the bow).

So why an ultra wide catamaran? How much sail a monohull can carry in a particular wind strength is determined by bulb weight, draft and to some extent by beam. For multihulls without keels, righting moment is achieved principally by the extent of the beam and this is one reason why in the past trimarans have typically been faster than catamarans - very simply, they are wider. With trimarans the main hull is structurally useful for supporting the cross beams, handling fore and aft rig loads and stepping the mast and being a convenient place to mount a daggerboard, however, when sailing, the hull itself represents unnecessary hydrodynamic drag and weight; two items fundamental in making a multihull go quick. So in theory if you could remove that centre hull, but keep the rest the same…

The D35s are a half way house towards this goal, having a centre hull, more of a fore and aft strut, out of the water, but strong enough to enable the forestay to be cranked up – an idea, to give credit where credit is due, first tried on Nick Keig’s Derek Kelsall-designed VSD cat back in the early 1980s.

With a beam of 6.9m or 65% of LOA (excluding the racks taking it out to 8.74m), the D35s still had someway to go towards reaching a typical racing trimaran’s beam and righting moment potential. And this is why the new Alinghi cat will be such an engineering masterpiece if she works. She has an unprecedented beam for a catamaran of her size, at we suspect somewhere around 80-90% of LOA, but her success will depend upon how well her structural engineers have succeeded in riding the possibly very fine line between making her crossbeams too strong and thus too heavy, thereby killing her performance, or, worse, too light and susceptible to breakage.

So what did we see yesterday?

The shape of the new Alinghi’s hulls reminded us of Team Philips, incredibly fine, with not much rocker (see Team Philips here). Even her ultra narrow bows, like Team Philips, have a wave piercing component to them, although the bows themselves are different, M2-style Dreadnought affairs designed to keep weight out of the front.

The boat also shares the same engineering nightmare as Team Philips in that she has a rear and centre crossbeam, but no forward beam. This is to reduce weight forward and the alarming tendency catamaran forward beams have to slam into waves (unless freeboard at the bow is enormous - and thus heavy - as it is on for example Orange 2). With the main central crossbeam around 50% of the way back from the bow this leaves a huge length of bow unsupported…and remember what happened to Team Philips… However in the Team Philips case the bow snapped off due to a build error that had resulted in the carbon laminate ‘blowing off’ the Nomex core in this crucial area. We suspect that given the exacting detail of the Swiss team’s engineers and builders this will not be the case here. Nonetheless the unsupported bows remain a questionable area of her overall structure.

In fact of Bertarelli’s past boats, the new beast is closer to being a scaled up version of not the D35 but his 41ft Seb Schmidt/Jo Richards designed Bol d’Or winning cat, known recently as Le Black. The significant difference between these two is instead of the D35’s flying centre hull, Le Black uses two fore and aft running centreline struts with considerable rigging beneath them to handle the rig loads.

Sadly what is not shown in the photos so far issued to the press [we were disappointingly banned from taking photos and video yesterday] is that there is a truly enormous bowsprit/beam extending forwards from the mast step to just beyond the bows. Plus there are two more beams diagonally straddling the aft and centre beams, angled in towards the mast step. Unusually these and the bowsprit/beam join on top of the main lateral crossbeam, rather than to the fore and aft sides of it, with the mast step in turn mounted on top of them.

Beneath these beams and the cross beams is a huge amount of rigging and no less than four dolphin strikers. The main dolphin stricker, the one that Alinghi Chief Sturctural Engineer Dick Kramers semi-jokingly refers to as ‘Grand Central Station’, is directly beneath the mast step and at the bottom of this is what Kramers calls ‘the spider plate’ from where carbon rods/'diagonals' extend forward to half way along the underside of bowsprit/beam, another set to a dolphin striker and then attaching to the underside of the bowsprit towards the end of its length. There are others carbon rods similarly rigged, attaching to the dolphin strikers on the diagonal beams and others across to the hulls beneath the main beam.

The idea behind this is exactly the same as why masts are stayed rather than freestanding. Aside from the tuning benefits, this is the best method for making the rig stiff and light. Similarly with the structural beams on the Alinghi maxi-cat platform.

Slightly odd-looking is that the two crossbeams are different shapes. The main central cross beam is two straight pieces with an angle in the middle, reminding slightly us of a Klingon battle cruiser, while the aft beam is more like a bird’s wing, arched at the ends, similar to what we see on the French tris.

While the two diagonal beams between the main and aft crossbeams are typically where on an offshore multihull you would plonk a central cockpit and a doghouse (as they did on ENZA) on the new Alinghi the cockpits are aft on each hull with presumably sail controls duplicated in each. We understand there is at least one pedestal in each cockpit, although we were unable to see this.

We imagine there will be a conventional rudder in the aft end of each hull and when we viewed her yesterday the daggerboards were not fitted. We suspect these will be interesting when they are unveiled as there are many possibilities for them. While we imagine they will be very high aspect, will they for example each be fitted with an AC monohull style trim tab like they have on the Syz & Co cat? Will they try and get some vertical lift component out of these foils or from an additional set of curved foils like the one found on ORMA 60 floats? We suspect the former is probable, the latter less so as it is just too heavy. Talking to the team members today we get the impression that they will not be trying to get their big cat foiling.

Those who were hoping to see the new Alinghi cat with the world’s largest solid wing rig will also be in for a disappointment. While the rig will be fitted over the course of the next couple of weeks it will be a conventional maxi-multihull arrangement with a substantial and impossibly tall rotating wingmast and soft sails and a very much smaller sail wardrobe than the Cup teams would be used to with their V5 leadmines. Also don’t imagine for a moment that there will be only one rig.

February is still seven months away and while the new Alinghi catamaran is built the team are expecting to alter it drastically over this time period.

Today the tent is being removed from around her and she will be exposed for the world to see. She is set to be transported to Lake Geneva on Wednesday. Alarmingly this will take place by Russian M126 helicopter with a lifting capability of 22 tonnes.

She will then move to her new berth at Bouveret just around the coast from Villeneuve and on 1 August will take part in a giant parade from Lausanne to Geneva as part of the Swiss National Day celebrations. Prior to this the boat will be rigged and will start her slow work-up process.

One of the most exciting parts of her future will be the transportation an as yet undisclosed port on the Med, again by helicopter…

A few more photos on the following pages...

Tomorrow we get the thoughts of designer Rolf Vrolijk and structural engineer Dirk Kramer on the new boat.