Lovely new technology

We compare the three new Open 60s - the Owen Clarke designed Temenos and the Farr PRB and Delta Dore

Friday November 10th 2006, Author: James Boyd, Location: Transoceanic

The Open 60 dock in St Malo prior to the start of the Route du Rhum ressembled a scene from the Cold War. With at least 12 new Open 60s either in design or build plus perhaps the same number again of wannabie Open 60 projects still lacking sponsorship, the dock was overflowing with shore crew, engineers, designers, skippers and other interested parties pacing out transoms, counting the number of bolts in main sheet tracks and guaging shroud diameters of the three brand new Open 60s in attempt to glean as much intelligence as possible.

The Vendee Globe in 2008 is going to be a truly sensational event with an unprecidented amount of new hardware on the start line and most of the world's top solo sailors competing. The Route du Rhum pre-start provided a glimpse of what we are in store for with the three brand new boats - the two Farr Yacht Design boats, 2004-5 Vendee Globe winner Vincent Riou's new PRB and Solitaire du Figaro winner Jeremie Beyou's Delta Dore, plus the latest Owen Clarke offering, Dominique Wavre's Temenos. Moored alongside the Lombard designs VM Materiaux and Sill et Veolia, as well as the Owen Clarke designed Artemis and even Christophe Augiin's Finot/Conq design 1996 Vendee Globe winner there was the opportunity to view Open 60 evolution first hand.

In a nutshell the key word to describe the new boats is 'power'. As Dominique Wavre puts it: "The general thinking is - the more powerful they are, the better they are. We noticed that with ABN AMRO compared to the Bruce Farr designs in the Volvo. Everyone knows that a powerful boat will be fast."

How one derives power from a canting keel Open 60 is more akin to a multihull than it is to a conventioal monohull, due to the movable ballast. All the new generation boats have huge rigs with spars in the 28m range and to offset the power of the rig by generating stability, the boats obviously have canting keels but also massive amounts of internal water ballast.stored throughout the length of the boat. They are also substantially beamier than their predecessors, all three of the new boats featuring chines in their aft sections, (which the previous generation of Lombard boats were the first in the class to feature). All these aspects go to make the boats more stable and therefore able to carry more sail area, in much the same way as increasing the beam on a 60ft trimaran.

For those still in the Volvo Open 70 mindset, the IMOCA Open 60 rule creates boats which appear on the surface very similar - they are both canting offshore race boats - but in fact the specifics of the Open 60 rule pushes designers in an entirely different direction. As Gilles Chiorri (below), Project Manager for Delta Dore put it to us: "First the weight of the bulb is not the same. The angle of canting is not the same - because we are limited to the 10 degree rule. The structure is not the same, and the attachment of the fin to the structure is not the same. We don’t have the same deal with the Volvo where every gram you save in the hull goes on the bulb."

While the Open 60 rule is far from Open, it is a great deal more flexible than the Volvo rule. For example it has no minimum weight restriction, nor is there a maximum or minimum bulb weight. The main driver for Open 60 design is the ''10 degree rule' where at standstill boats must heel by no more than 10 degrees either side with all their moveable ballast deployed.

Without this rule it might be possible to have a very skinny boat with a massive bulb, like the Reichel Pugh maxis. In the event it is the 10 degree rule which pushes designs towards being ultra-wide thereby gaining form stability from the hull which provides effectively 'free' stability under this rule. According to the official race program numbers Geodis (currently Philippe Fiston's Maisonneuve Basse Normandie) is the beamiest Open 60 in the Route du Rhum at present at 5.95m wide, while Ellen MacArthur's 2000 generation Kingfisher (now Marc Guillemot's Safran) is a mere 5.35m, the last generation Lombards are 5.5m, the last generation Farr design ( Virbac Paprec) is 5.4m. Meanwhile the new Temenos is 5.5m as is Delta Dore while PRB is a whopping 5.85m. In fact these numbers are almost certainly nonsense - most believe PRB to be closer to 6m and Delta Dore a shade narrower. Bear in mind that the new boats all have chines as a way of creating additional form stablity in the hull aft while saving weight - imagine creating a 6.3m wide boat and then chopping the deck off vertically down to the hull, 0.5m in board down each side. Without chines the overall beam of the new boats would be well in excess of 6m.

The whole interaction of stablity generators is a lot more complex for Open 60s than it is with Volvo 70s. More hull form stability not only means you can have a more powerful, heavier rig, but a heavier bulb. However the biggest difference is that Open 60s are not restricted in the amount of water ballast they can carry. While carrying water ballast in outboard tanks, as they used to on Volvo 60s and water balllasted Open 60, is expensive with respect to the 10° rule, the norm on canting keel Open 60s is to carry removable water ballast in tanks along the centreline forward, aft and even in the centre compartments of the boat. Ostensibly this allows the skipper to alter the fore and aft trim of the boat - to lift the wide, very sticky transom out of the water when it is light, lift the bow out in hard running conditions, etc. It also allows the displacement of the boat to be changed - you can have a 'light' mode for reaching and running and a 'heavy' mode to give the boat more momentum going upwind in a big wind and waves. In this respect Open 60s are perhaps the most versatile sail boats afloat.

However more subtle is that this centreline water ballast is also an effective way of cheating the 10 deg rule. Fill up all the tanks and the boat sinks increasing its water plane, upping the hull form stability, thereby allowing more lead in the keel, etc. As a result one look inside the Farr boats and you realise the extremes they have taken this to. We had a look around Delta Dore and even in her middle compartment the water ballast tankage seems to take up most of the floor area (somewhere in the middle there is an engine and transmission obviously) and one imagines there is similarly copious water storage in the forward and aft compartment. As Gilles Chiorri wittily acknowledges: "For sure these boats are closer to tankers than sailing boats for upwind and reaching conditions! I won’t tell you how much the displacement is increasing when you are upwind and reaching, but it is quite impressive." If the boats are not capable of doubling their displacement when all the tanks are full then it cannot be far off this figure. In fact this type of tankage appears even on boats built for the 2000 Vendee Globe - Kingfisher had them, for example - just now the tankage is more extreme. On Delta Dore in fact it is so extreme that the rear end of the aft tanks are visible through the transom.

Compared to the Volvo 70, the whole displacement game is also very different with Open 60s. As there are no weight restrictions Open 60s have found their own natural displacement at around the 8-9 tonne mark (ie around 60% that of an VO70) and thanks to the 10 degree rule it doesn't pay to transfer every gram saved in the hull into lead on the bulb or to have an extreme canting angle for the keel. Potentially this makes the boats safer as with a substantially lighter bulb and foil package, the internal structure holding it into the boat can be strong while relatively light, nor is there much call to go for hydraulic rams made from exotic materials, although the better funded projects inevitably will go down this route and we understand for example that in order to save weight at present PRB only has one ram, as opposed to two as normally found on Open 60s.

Open 60s also don't have the added complexity of allowing the keel pivot point to be inside the hull, but at the hull exit and so there is no need for hazardous 'bomb bay doors' or any other device to close the aperture in the hull when the keel is canted as is the case on the Volvo 70s.

Working out how to optimise this complex bulb weight, rig weight versus beam and water ballast relationship is where Open 60s designers spend considerable time.

The other area is rigs. One of the joys of the Open 60 class is the variety between the boats and nowhere is this more apparent than what goes on above deck. During the last Vendee Globe we published an article looking at the different rig configurations being used in that generation of Open 60s (read this here). One might think that the Open 60 being a relatively mature class a trend would have been found with all the boats heading in one direction - not a bit of it! The three new boats in the Route du Rhum all have different rig configurations.

The general conundrum is that rotating wingmasts are capable of generating more lift than fixed rigs however they are heavier. So another area designers expend much computing power number crunching over is the price of having a higher centre of gravity and more power bearing in mind that this is another parameter that will have a considerable bearing on whether a boat meets the 10 degree rule.

In the end choice seems to be largely based on skipper preference. Mike Golding for example prefers a relatively small but efficient sail plan and so on Ecover has a wingmast with a small cord, two sets of diamonds and hinged spreaders that rotates within a fixed set of shrouds. Alex Thomson having had a wingmast on his existing Hugo Boss until it jumped ship earlier this year, says he carried out tests on it at sea and couldn't see a noticable improvement in performance from rotating his spar and is thus going for a light weight fixed rig for his new Hugo Boss. Dominique Wavre has similar ideas to Thomson about his choice of rig and as with his old boat, the new Temenos has a fixed rig, but a humungous one. "I like the rig to be light and high by keeping the classic configuration," says Wavre, who adds that the sail plan is in fact much the same size as his previous Finot/Conq designed Temenos (currently being sailed by Kojiro Shiraishi in the Velux 5 Oceans). "The speed box is a bit different, but the general philosophy for the two rigs they are more or less the same."

Meanwhile the two new Farr boats both feature wingmasts, but this is where the similarity ends. On the previous PRB (now Anne Liardet's Roxy racing in the Route du Rhum) Michel Desjoyeaux's original rig, when the boat was built, was rotating and had a single set of hinged spreaders, with which the boat won the 2000-1 Vendee Globe. When this rig was subsequently dropped, new skipper Vincent Riou replaced it with a lightweight triple spreader fixed mast and with this won the 2004-5 Vendee Globe. With the latest PRB Riou has gone for a third different rig configuration, reverting to the wingmast and deck spreader set-up, originally introduced by Yves Parlier on Aquitaine Innvoations in the mid-1990s. Parlier wanted a multlihull-style wingmast rig on his Open 60 and to reduce weight aloft (remember the 10 degree rule...) fitted the boat with spreaders protruding out either side of the deck, giving the boat a look of a trawler, but effectively emulating the wide shroud base found on ORMA 60 tris.

Obviously the deck spreader rig has evolved considerably over the last decade. Both Lombard boats about to win the Route du Rhum have this set-up and the length of the deck spreaders is substantially reduced on both them as it is on the new PRB. Aside from reducing weight aloft this rig configuration is aerodynamically very very clean and also allows headsails to be either sheeted from the deck spreader or within the shroud allowing the slot to be as small as you like.

Delta Dore's rig on first glance appears to be a conventional three spreader fixed mast. In fact her mast has a wing profile and rotates as all three sets of spreaders hinge, thus making this rig a first in the class. Built by Lorimar, the rig was developed by Herve Devaux Systems who's engineering talent features in many of the top multihulls as well as ABN AMRO. "Jeremie didn’t want deck spreaders but wanted a rotating mast," explains Gilles Chiorri. "So this is closer to Maximus or Ecover than the first PRB. The angle is quite important and the set-up must be quite accurate."

"Surely there is a lot of friction in the system?" we put it to Chiorri. "No, because the spreaders are on a ball pin - you pull and it turns. In fact if you check carefully where the runners attach to the mast, you just pull on the runner and the mast turns. So it is a natural effect. In fact when you sail you keep the clutch for the mast rotation open and the mast goes exactly where you want it to g - that is a good point in terms of development because it means everything is balanced."

Another considerable variation between the three boats is in their cockpit layout. While Temenos has a conventional singlehanded companionway down below, lines running back from the mast internally down both sides of the cabintop, the Farr boats, like Virbac-Paprec, have them all running directly back from the mast through a centre tunnel to a single bank of jammers and one utility winch. The evolution of this 'tunnel' is that on Virbac it is straight while on PRB and Delta Dore it has a hump in it to allow more headroom at the chart table down below. According to Gilles Chiorri the height of the utility winch on the new Farr boats has also been changed so that rope can go around the utility winch and back to a primary which he says you can't do on Virbac-Paprec.

Both Farr boats have twin kick-up rudders, while Temenos has fixed rudders, but all three boats have different helm arrangements. On Temenos Wavre has gone for twin wheels, as he explains: "French people tend to come from dinghies, the Figaro or the Mini, while I come from America’s Cup and Whitbread, so I am used to wheels. I like to be precise. Also weight-wise there is not a big difference now. They are titanium wheels, carbon car drums, Vectran rope, etc, so it is very light. I prefer that because I get a better feeling steering and that makes me want to spend more time doing it."

PRB and Delta Dore both a single tiller arrangement in the middle of the cockpit. The PRB set up is tiny and looks like it has come off a Mumm 30, while on Delta Dore they have a much more complex custom built arrangement where the tiller is fixed but can be rotated from side to side with a built in extension that moves fore and aft (poorly explained - you need to see the photos).

In terms of winch power, the Farr boats have gone minimalist with one ultility winch, twin runner winches and two primaries driven by a central coffee grinder. On PRB the winches are mounted further forwards and there are holes in the deck allowing sheet tails to be fed down below out of the way.

Of the three boats we were only allowed down below on Delta Dore. Centrepiece as ever is the chart table and this is mounted forward on the aft side of the main bulkhead with an impressive dished seat that not only moves from side to side on a track, but can also move fore and aft on another set of tracks to allow access to the engine compartment. Generally the centre compartment is very open plan with a bunk and stowage on each side and a smart carbon fibre galley tucked beneath the 'tunnel' on the forward side of the cockpit bulkhead, where there is sitting headroom only. We understand the layout is similar on PRB but more minimalist still.

All three boats also have different vang and gooseneck arrangements. Temenos has the conventional Open 60 format where the boom attaches to the deck immediately aft of the mast foot with the vang effectively a line running the length of the boom which is cranked down to the deck. Both Farr boats have the boom attached to the mast. On PRB one aspect of the old boat Vincent Riou has incorporated into his new steed is the long C-shaped track that is used to crank down both the mainsheet and the vang. On Delta Dore the vang is a more typical keel boat arrangement.

Gilles Chiorri outlines their philosophy: "With the conventional boom vang on Open 60s you can’t control the leech in the same way. Ours is very powerful. These boats are quite overpowered when it is windy and the fact is we are increasing sail area because we are looking for power in light winds and if you take a look at the boats in light winds, the leech is completely open, so of course we will use a conventional vang like the other 60s in very bad weather but in light weather you have much better control." The Delta Dore vang is part purchase, part hydraulic.

Other hydraulics on Delta Dore are for the downhaul for the ORC (staysail) and the solent (100% jib). Delta Dore has hooks (made by Karver) on her Solent and ORC, while PRB also has them on her gennikers.

As the Open 60s have canting keels, so they must also have boards. All three boats have twin boards. Once again Farr have gone with boards that are more upright in the boat and these are slightly aft of the mast whereas the boards on the Owen Clarke boats are slightly forward of it. Oddly on Delta Dore the boards are symmetric rather than the more efficient assymetric shape which Gilles Chiorri says is a safety feature allowing the boards to be exchanged in the event of one being broken. Generally all the boards are longer than the previous generation.

Such is the variation between these boats that this article could probably go on forever. However these are just the first offerings. Launching next year will see the latest Open 60s from Finot/Conq, Juan Kouyoumdjian, more from Farr and Owen Clarke as well as the boats from the new team of Guillaume Verdier and multihull designers Vincent Lauriot Prevost and Marc van Peteghem. Exciting times.

A lot more photos on the following pages...

See video of the new boats (along with other Route du Rhum Open 60s) in action here - NB this is a particularly big WMV file so don't attempt to open it unless you have fast broadband

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