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Old 04-15-2013
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Canting keels

Since we are talking about them let's have a historical prespective:

The first one was invented and patented by the great Hereshoff himself in the XIX century yet. For the ones that don't know him Hereshoff was the Leonard Da Vinci of boat design: He designed fin keels, canting keels, and catamarans when there were not available resistant, light and stiff materials to build his inventions on a sustained basis. I never saw the design and I would love to, so if somebody has it or know where I can look at it, please say so.

The next guy to use the concept was Jim Young back in 1957. I had posted about him:

Interesting Sailboats

The system did not seem much reliable and the boat, Fierry Cross, keep it only for a short time, beeing replaced for a fixed one. I don't know if that was due to technical problems or just for the boat to be able to compete.

Sail-World.com : Jim Young: A Contrast in Hull Forms

and the story goes on on the Micro and Mini racers probably the boats were more experimentation was made in the last 30 years. The first one to use the concept was Pascal Conq in, a kid that was also a NA student and a sail racer, back in 1982. He rediscovered the concept (did not know nothing about the previous attempts) and his keel is the one that give origin to the modern models. Contrary to the other two that was the only one that come inside the hull.

Back in 1981, the Micro rule is the only rule that cares about innovation in yacht design, although it is more of a rectrictive than open rule. It is also a rule meant for small budgets. Not a detail for 20 year old students!

Pascal and his pals brainstorm : Like him, Paul-François Coustou studies architecture in Rennes. Yannick Dupetit is his cousin, and together they will win the Tour de France à la Voile in 1985. They start from a blank sheet of paper, and apply the new thinking methods they are learning from their studies.

Pascal proposes to cant the keel to move its center of gravity to windward, thereby increasing the boat's righting moment. As far as they know, no one have ever done this, but they believe in their idea. They are not to be stopped !

Of course, on second thought, it is easy to see that this size of boat isn't the best to show the full potential of this innovation, because the weight of the crew has a far greater influence. But despite a few teething problems (rudder failure in Toulon, crash in Granville), they win a leg... in Granville in 1984. The same year, they take third place in the Tour de France à la Voile, and have an easy win the following year.

1985 is also the year when Pascal graduates from Architecture scholl and meets Jean-Marie Finot...


Those were the days



Jean Marie Finot, already a major NA was so impressed that invited him to work with him and later give him equal status on his firm (Finot/Conq), a firm that today continues to be an innovative and major one.

finot-conq architectes navals

In the words of Pascal Conq:

In 1982 with 2 buddies, I designed and constructed a Micro cupper that was called Urgent,with a canting keel. I was thinking it was the first canting keeler ever build. (More info Bateaux sail magazine on the Micro of 1982 and 1984).

Our research of stability involved crew displacing, stacking (all loose material inside boat) and a canting keel. It is a very heavy part of the boat that is geometrically easy to move from side to side.

Then we designed a canting keel for Michel Desjoyaux in 1989 on a Faroux minitransat and for Isabelle Autissier on her first Open 60, a design of Berret.

Then in 1997 Christophe Auguin participates in the Vendée Globe on a 60 feet with canting keel drawn totally by our office. It is the first boat to accomplish a tour of the world with this system.

The advantages:

One can increase the stability of the boat considerably, 50% more then normal keel in the best case. This while increasing the mass of the boat little. (system about 5% of the weight of the boat).
So be carrying more sails, a gain of speed upto 15%.
The system of the keel permits it to adapt quickly to the conditions of navigation's.


The inconveniences:

1-A lot of complexity around the axes. New source of mechanical problems that must not be treated to the light. Conception, manufacture and placement must be of a big quality.
2-A cumbersome system in the center of the boat, that also poses a problem of water tightness.
3-More expensive.
4-The lift force of a cantingkeel is bad, so you have to install a more complicated daggerboard.


The 29, that revolutionary boat, is still racing in Mini class races.

And of course great sailors have to be mixed in the story. who was that thought that the concept was valid and have the first to win in one? Of course, the two times vendee Globe winner, Michel DESJOYEAUX, when he was just a little more than a kid. In his words:
...
Harken made and launched in 1991 a cruiser "concept boat" wich was with, winglet canting keel, bipode mast, on rams. ..

In the same time, I made the first offshore race with one on a Mini Transat in 1991. I broke my rudders in the first leg, and won the second leg. ...


cantingkeel 29

Canting keels : A 30 years story ! | finot-conq architectes navals



A long story that starts on the XIX century with an Idea that has his first race offshore victory in 1991. 22 years of story. Not much bit a big evolution an evolution that is far from being finished.

I have saw along the years some performance cruisers with canting keels. The next step will be the first production boat (in considerable numbers) with one. Some say that it would not ever happen. I am pretty sure they are wrong

http://www.mshipco.com/pdf/SailingWo...TF_Sep2008.pdf

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Last edited by PCP; 04-15-2013 at 12:09 PM.
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