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Manuard C40 & IMOCA 60 interview

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Interesting article, but in French....

So here is my translation of it!

The architect Sam Manuard explain his Mach 40 Mark IV and hints of an original IMOCA for Armel Tripon

Samuel Manuard (à gauche) et Nicolas Groleau (à droite) ont déjà construit douze prototypes de Mach 40 avec un palmarès remarquable.
Samuel Manuard (left) and Nicolas Groleau (right) have already built 12 prototypes Mach 40 with an impressive winning record. | DOMINIC BOURGEOIS
Interview by Dominic BOURGEOIS.

Voiles et Voiliers met the sailor-architect Samuel Manuard at the shipyard JPS Production led by Nicolas Groleau at La Trinité-sur-Mer. Manuard has entirely revamped his design, for a new Class40 prototype. Spatulate bow, large volume forward, wide, rounded chines, this Mach40.4 will look like a scow. Here are some explications... and a few bonus questions about the 60ft IMOCA for Armel Tripon for Vendée Globe, designed by Sam Manuard as well...

A new Class40 designed by Sam Manuard is going to be built by shipyard JPS... How many boats of this class have you built since the beginning ?

With JPS Production, we started in 2011 with n° 104, the first version of the Mach 40 for Alois Claquin (Vecteur Plus, now named Volvo for Jonas Gerckens). Before that, I had designed one in Canada (n° 35, Bleu in 2008) and one in Italy (n° 84, Cala Luna in 2009), and then in 2012 another one in Italy (n° 117, Bet 1128) and finally a last one in 2014, still in Italy (n° 136, Kika Green).

Then there was a second version of the Mach 40 built by JPS Production for Sébastien Rogues in 2013 (n° 130, GDF-Suez now named Imerys for Phil Sharp), then a third version in 2015 for Maxime Sorel (n° 144, V & B). All in all, I designed 12 boats built at JPS Production in La Trinité-sur-Mer; two Mach 40.1, three Mach 40.2, six Mach 40.3 and the newly Mach 40.4 (n° 159, Banque du Léman for Valentin Gautier) which must be launched at the end of the month. To those, you have to add four BM40 (Canadians and italians), but there are completely different design from the Mach40 built at Nicolas Groleau shipyard…

The concept of the scow became obvious

Let's focus on the Mach 40 : why those iterations ?

Between mark 1 and mark 2, there was no significant change, other than the keel and the rig moving aft by a fair amount. On the other hand, in 2015, it was a major update on the Mach 40.3 with a new hull. Today's version is even more different, getting closer to the shape of a scow.

Pervious Mach were based on optimisation of the same concept, but here, we made a lot of CFD and VPP modeling, to find out if there were a significant gain, with much more voluminous shape. In the end, the scow concept made us win, in the models, the Route du Rhum, the Transat Jacques-Vabre, the Normandy Channel Race and the Rolex Fastnet Race


What does the scow concept brings to the table ?

Its behavior in seas, off the wind, is better because it can stay above the waves, instead of punching into them. Today, in Class40, just like in IMOCA, the boats have enough speed to catch up the wave upfront, and punching through a wave, it is slowing down!
So you have to have the boat to pitch up more and more, with high volumes upfront and spatulate bows, so you have less tendency to punch through waves. So I designed a scow, within the limits of the Class40 rating. 20 cm from the bow, the width must not be more than 45 cm, and you are not allowed any inflection points on the hull curves. So we draw some tengential lines, to be at the max volume shape: the first third of the boat forward is therefore very wide, but the max width is still more or less in the same place than before.
MjAxOTA5ZmUxMGNiZDI5NTRjNTU1ZGQxM2FiNzBiZGQxNGJmZmQ?width=630&height=0&focuspoint=50%2C50&cropresize=1&client_id=bpeditorial&sign=13f233e8de2bb4c057493c0ce7b9dc82091f473c10e385e5b28cf06de13271f9 The« spatule » of the Mach 40.4 : LWL is significantly reduced, but this shape for the forward third of the boat significantly reduce the risk to "nose dive" when sailing off the wind. | DOMINIC BOURGEOIS

So you have a lot of volume upfront !

Yes, the width of the first third of the hull brings a lot of form stability; the spatulate form and the rocker of the first third of the boat reduces the risk to nose dive in the wave upfront when you catch up with it. LWL is therefore significantly reduced.

But everybody says to increase LWL to increase speed…

It is true for high displacement boats. But for Class40, the mode of operation is a bit different, because they quickly get into planning mode, or semi-planning mode. The loss of LWL is well compensated by the fact that we get more righting moment, with a higher potential for acceleration.

So it is "spatulate" at the front, but then all straight lines aft, like a waterski???

We tried to find a good compromise between straight lines and full lines. Straight lines give potential for acceleration, but fuller lines are more versatile and forgiving. Some rocker haft also help the boat to pitch up. On a boat, you cannot completely isolate a  single parameter. The hull shape has obviously an important impact on the behavior of the boat, but you can also play with the lateral and the fore and aft ballasts to adjust the longitudinal and lateral attitude of the boat.

Comparing to the Lombard design that won the Route du Rhum, or the David Raison design that has been built at JPS Production as well, what are the major differences?

There is a tendency to search for more form stability, and find ways so the boats don't hit the waves so much off the wind. But with three different hull forms, because there are three different architects!  We use neither the same tools nor the same approach to the problem. I tried to design a pretty radical Class40 with little compromised on hull shape.

Comparing to Mach 40 MarkIII, you are hoping for how much performance gain ?

We will see on the water how it goes. But on paper, Mach 40.4 is more radical where the Mach 40.2 is very versatile. Clearly, the new design will love reaching and broad-reaching, 60 to 120 degrees off the wind. In fact, we think that there is not that much difference in boat speed beating against the wind, which is not that common anyway during a transat race. It is true though that the version 40.2 will most likely be easier to make go fast off the wind in strong winds or in very light winds.

The scow has a much larger wetted area for light wind sailing !

It is a little bit the unknown… You will also have to take into account the shape of the sails. The Class6.50 minis which launched the "fashion" of the scow have a canting keel and a tilting rig, which is not true for Class40. But the gain is still very important ! You will have to quickly sailed heeled, to reduce wetted surface area and increase form righting moment.

In best cases, there is a boat speed difference of 2 knots... Off the wind, the advantage will also depend on the sea state, and how deep you want to sail. The Mach40.4 is very much a blue water race boat; if you have to luff to catch the next weather system, it will be a very potent boat. The Lombard design is less powerful than the David Raison design and than the Mach 40.4.

The last designs move more and more aft the keel and the rig : is it also the case on this new prototype ?

We worked a lot on the rig, and a bit less on the appendices. There are several limits by the Class40 rating : the total height above water (we tried to lower the gooseneck as far as possible) and the total sail area, main + genoa. So we moved aft the mast step to increase the aspect ratio of the main and increase the genoa surface area.

We also noticed that there is no hard chine…

This is new, rounded off chine. It is a way to better spread out structural stresses. You have to remember that Class40 are not allowed to used carbon fiber. Which means that the Class40.4 is even more framed, with a lot of bulkheads, to cope with even greater loads, especially in the forward third of the boat. The boats go faster and faster, and hit waves harder and harder.

But displacement is similar to previous versions: the distribution of the frames is different, and the transom area is straighter than before. It is the concept of the scow : as soon as you heel 10°, you have a much narrower hull in the water. So you gain on wetter area. And off the wind, the boat can heel up to 25°.

MjAxOTA5MmZiM2U5Y2YxNTFiZmJjM2QyZTQyN2Y2MDE4M2Q0NDI?width=630&height=0&focuspoint=50%2C50&cropresize=1&client_id=bpeditorial&sign=24788ce66ca94a918dcfe9c7ae8efa71f42f14435913b5d6f5ff2ef82cb94ed3 The rounded chine helps better spread out the structural loads of the Class40. | DOMINIC BOURGEOIS

So the Transat Jacques-Vabre will be the first real test !

Even if there is only 3 days of broad-reaching, the advantage will be for the Mach 40.4, but if there are some pretty complex conditions, the previous versions will do well, because the crews know their boat inside out. It all depends on the weather conditions, but we already have two or three orders at JPS Production.

The number of new prototypes seems to be pretty stable since 2015 : before that, we had Class40 séries…

Most likely, the shipyard Structures will be back in the game for Route du Rhum 2020. Most likely with a Verdier design… If there are less architects in the game, it is first and foremost because there are less Class40 being built and less shipyards building them.

Something special about Sam Manuard, is that he is also a racer !

Only a little bit this year. It is because I had a string of design projects and they take time. I sailed the Fastnet Race on the 45 footer Bretagne Telecom (2e en IRC Z). You cannot do everything…

Regarding the deck and cockpit layout of this new prototype…

The trend is towards protection of the skipper, with good forward visibility, so you can be on active watch without being continuously soaked, even if the new design are less wet. It is an important aspect for the skipper, less loss of energy.


MjAxOTA5MmMzNGU5NTY4NWI1ZDQ2MmIzMzc4YmQ1Y2ZkYmQ0Y2U?width=630&height=0&focuspoint=50%2C50&cropresize=1&client_id=bpeditorial&sign=2c8b621a604b4bb1fa640c5a9a0a873957155eba7d8a45e297ba15c721d83942 If Sam raced less than previous years, his offshore race experience still influence his designs. | DOMINIC BOURGEOIS

Let's talk about your future IMOCA being built for Armel Tripon : is it inspired from this Class40 ?

JI cannot say too much, but it is quite unique an IMOCA. It will be in Nantes in October at the Black Pepper shipyard, with splashing water at the end of the year.  L’Occitane will be significantly different than what has been launched lately, both about the foils and the hull shape… On these 60ft monohulls, the first difficulty is to define the concept of what you want to do. From there, you define the foils, which are now a key element, then the hull shape and the the rig. Between the designs by Juan Kouyoumdjian, Guillaume Verdier and VPLP, you have different philosphies, or even diverging philosophies. Ours will be different, fairly unique !

BUt how do you define this initial concept ?

You define the key points over an entire Vendée Globe. We asked ourselves: what are the critical phases on a Vendée Globe, and what do we want to optimize? We are not starting from a blank sheet of paper, but the new generation of IMOCA is completely different from the previous ones!  Of course, we look at the overall weather encountered during the previous races, but even if yach design is scientific, you still have to make decisions, make choices : options depends on the skipper, even if statistical routings is the same base of analysis.

You have to know that the average wind on a Vendée Globe is between 18 and 22 knots, that most sailing is wind angle between 70° and 120° TWA. This is essential to design an IMOCA. After that, the architect is going to work on the more specific phases of the race we want to improve (equator crossing, going down South Atlantic, Southern Ocean, coming back from Brazil...). There is also the intent to stay before a cold front, or how to cross a ridge. And then you have to look at the easiness to manage the boat: do you want a very high performance blaot, but hard to tune in, or instead a more versatile design, easier to bring to full potential?

Anyway, you can expect an original IMOCA…

MjAxOTA5NGQ2OWE5Mzg3MjVmNzI3OWRjNDc5N2JiN2YwMmE0MGU?width=630&height=0&focuspoint=50%2C50&cropresize=1&client_id=bpeditorial&sign=860c3089cb5707c76892bdb3aa3e16a806a8248d7bf617ace9815325b91b7f00 The specific shape of the new prototype by Sam Manuard should be very effective, off the wind, during the Transat Jacques-Vabre. | DOMINIC BOURGEOIS

Today, do you have to have curved foils?

Overall, you have two big families of foils : the ones with a « shafts » with inward curvature (usually Verdier design) which allow to adjust the « cant » of the foil (lateral angle of inclination) and the « shafts » with an outward curvature (usually Juan Kouyoumdjian design) which forces your to extend the foil  fully when going upwind and then progressively retract it as you go more and more off wind. Personally, I work with Nat Shever who designed the final version of foils on boats of the America Cup after Emirate TNZ, and Groupama Sailing Team and today American Magic.

Let's come back to the new Mach 40.4 : when will it be launched ?

September 26th, to follow up with the Transat Jacques-Vabre (27th of octobre) with Valentin Gautier and Simon Koster.

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