SH: So can a ‘mini Class40’ be competitive in IRC? EL: I wouldn’t say this is a mini Class40… but its hull shape could look closer to that than it is to some IRC boats! We have an IRC-friendly straight keel with no bulb and a genuine but lightweight cruising interior that we hope will enable us to attract some clients looking for a performance cruising boat; remember that is how some of the early Class40s came about.
The IRC rule works well – today no boat can dominate in all conditions – but we are confident that with this boat we have delivered a great compromise solu- tion for offshore sailing. The MC34 has won its class in the last two Fastnet races and this design is a significant improve- ment on that boat. SH: We are seeing many modern IRC designs – particularly those from France – using a straight-keel, twin-rudder configuration. Why do you think this is, and what are the design considerations when designing the keel and rudder profiles and locations at this size? EL: Straight keels and twin rudders are two separate design choices. First of all, I’ll tackle straight keels: I don’t think they are a ‘French’ trend – many of the IRC-optimised Quarter Tonners in the UK use straight keels as well. I view the straight keel as a no- brainer under IRC in this size range because bulb keels are heavily penalised. In terms of keel design, if you don’t have a bulb then you need a keel fin that is large enough to include enough lead to give the
Ofcet 32 – a generous cockpit includes ‘mini-benches’ where a crew can monitor things when under pilot. The base price of €140K (ex-tax) includes a high-modulus carbon rig with a sailaway price of €175K
boat the required stability. You end up with a large surface area that does an excel- lent job of providing lift and reducing lee- way but there is also some more drag (which we have spent a lot of time trying to model and reduce through CFD studies). It’s true that twin rudders are more of a feature on French designs, probably because in France we have more of a cul- ture of shorthanded offshore sailing and of sailing in boats with hull shapes designed for that. With modern offshore hull shapes (with broad transoms) the centre of the transom lifts quite high out of the water when the boat is heeled, so if you wanted a single rudder it would have to be posi- tioned quite far forward which in turn would make the boat very twitchy and dif- ficult to sail. Twin rudders are an obvious solution for offshore-oriented hull shapes and the control they offer is an added
bonus when racing shorthanded. When looking at rudder position, it’s also important the rudders are far enough back and sufficiently angled out that the windward rudder does not drag too much at normal heel angles. It’s also good if the rudders are as close as possible to the tiller so that the system linking the rudders to the tiller can be simple, lightweight and low in friction. SH: Have recent changes to the IRC rule influenced your design? EL: To some extent – lighter-weight boats are less penalised than they used to be. We hope that trend continues! SH: 32ft is shorter than the average boat we see racing in series like the RORC points championship. What about plans to scale up the design… EL: We think 32ft is a great size for a shorthanded raceboat. The smaller the boat the more manageable the loads and the closer you can get to 100% of the boat’s potential when shorthanded. For example, on a 32-footer the helm can adjust the mainsheet and the traveller line with his second hand – even at 35ft that starts to become very difficult.
That said we are working with Yann on a 40ft version that would be suited to both shorthanded and crewed sailing. And at Marc Lombard Design we also have a larger custom IRC 46-footer underway which is again designed around a dual crewed/doublehanded programme. Yann Dube and Eric Levet were talking with Joe Lacey
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