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Old 03-01-2005
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How heavy is too heavy II ?

I was posting this in the thread “HOW HEAVY IS TOO HEAVY” but the thread has just vanished, so I am opening a II thread with the same name to continue the discussion (hope she come back).





I find this thread very interesting. It goes in the direction of the kind of boat I am interested, I mean ocean going, easy (solo crewed), comfortable, safe, fast and reliable. Of course we are talking of boat compromises and in particular of the role mass has on those compromises.

I was having in another thread an interesting discussion with Phil that is exactly about this subject, so I will bring it to this discussion. I would like to have your opinions.
We were discussing the new Swan 46 that very surprisingly turned to be a medium displacement boat, opposing the trend of all the other boats in the line, that are fast cruiser racers.
Why a high-tec. advanced design company would do that kind of boat, a heavy boat, an old design boat for some?

But first let me sum up what was said in the other thread that is relevant to this discussion .

I have said in another thread:

....And about sailing, there are many differences in the kind of sailing (traveling). There are the ones that want to go as fast as possible with a full crew, others want good speed but a boat that can be easily solo sailed, others want maximum comfort in a seaway others an optimized safety, for the size of the boat. There are a lot of compromises to be made (in hull shape and rig), originating completely different boats, depending on the assumed different priorities.

The only disagreement (possibly) with you has to do with this statement:"..."others appreciate the craftsmanship of fine joinery and designs that give a nod to tradition but acknowledge contemporary developments in keel/hull form and aerodynamics, albeit with little regard to weight reduction."

It seems to me that you think that weight (mass), besides the one needed to give the boat stability) is always a bad factor in a sail boat.

Although I agree that mass is always a bad factor in a racer or even in a cruiser-racer, it is not (in my opinion) in a pure cruising boat with priorities aimed to have an easy motion, maximum safety and lots of autonomy.

And I am not the only one thinking that way. Take as an example the new Swan 46. Swan are well known by their high-tec, luxurious cruiser racers (but also winning ocean racers), but recently they went to the old cruising roots and made a purely cruising boat, the 46.

The boat displaces 39 000 lbs. Compare it with the displacement of the Swan 45, a cruiser racer that comes in two versions : in the more racing version, 19 150 lbs and in the "cruiser" version, 23 920 lbs. The extra weight of the 46 doesn’t find its motive on a question of money ( kind of thinking – lighter, more expensive) because those guys don''t look at costs, just quality (both boats cost over $700 000, being the 45 the "cheapest".

It is obvious that the Nautor Company technicians believe that mass has an important role to play in a purely cruising boat and they surely know what they are doing, having lots of experience with racing and cruising boats.


Phil replied in the other thread:

...” Ballast weight should be maximized as deeply as possible while all other displacement contributors should be minimized to the extent it is possible within the design parameters....

The intuitive argument has often been made that increased displacement produces better motion comfort. Some also feel that it’s necessary for robust construction. Both of these claims are false.

I do not believe that Swan intentionally built the 46 to be heavier, only that they were appealing to customers with different priorities. Luxury equipment and solid wood joinery are not light and the people who are drawn to this yacht place a higher priority upon these things than sailing performance, simple as that. They did not make the boat heavier to improve motion or strength.

As it has been stated here before, if you are willing to pay for greater displacement, which is another way of saying “a bigger boat”, and you wish to maximize motion comfort, buy a longer waterline length instead. You will get more interior space and greater speed as a free bonus! ... My guess is that either of the Swan 45s will be much faster, more comfortable and easier to sail too...”




Phil, I don’t agree.

The Swan 45 interior is absolutely lavishly and of course also made of solid wood and you can believe it, nobody gives $700 000 for a boat of this kind if it is not a “very special” and luxurious boat.

I think they made the boat heavier to make it rock solid , and to give a boat a slightly curved hull (not flat). Both things will improve motion and contribute to give the boat an easy controllable handling.

I don’t think you are completely right when you say : “.....” Ballast weight should be maximized as deeply as possible while all other displacement contributors should be minimized to the extent it is possible within the design parameters....”

It is well known that a dismasted sail boat is much more easily capsized ,but the same boat with the mast (weight of the mast) has a higher center of gravity.

If I agree that a boat should not have a high positioned weight it is known that a distribution of the weight all around (below the waterline) contributes to an easy motion (that’s why steel boats have an easier motion, compared with similar GRP boats of the same weight). A deep keel with a bulb certainly contributes for a lot of initial stability but not for an easy motion, quite the opposite.

About buying a bigger boat. Regarding motion I found that you are partially right (bigger boats have a better motion). The boat, if it is a cruiser- racer (light, shallow hull, big sails, deep small fin with a bulb) will continue to have a difficult, sharp and nervous character. After all it is made to be crewed with a lot of people and to be a quick boat, not only in speed but in all of its reactions.

Also the bigger the boat, the bigger the sails (you could say that because the boats have the same weight, the sails would be the same size, but that is just not true. The bigger cruiser racer will have always sails a lot bigger than the smaller cruiser boat with the same weight) and that will make the boat more difficult to sail alone.

There’s another three dissuasive important factors in a bigger boat:

1- costs , not really the boat but the marinas and maintenance prices are a lot different between a high displacement 39ft and a light weight 48ft.
2- other problem, at least in Europe, is that in many Marinas, no matter what you pay, you just don’t have places for boats of that size, and I don’t mean one or two, I say a lot of them, specially the nice old ones, in typical fisherman towns.
3-And finally, even if you can find a place, most of the marinas around here are not made for big boats so you just have a lot of trouble to put the boat in and out and forget about doing everything alone (I suppose most of us can do it alone with our boats), it is just not possible, even with a bow thruster (you have to push the other boats to fit in).

Of course, there is a fourth reason that I haven’t even considered. If the boat is heavier that means that probably it is stronger. I believe modern light boats will not have any strength problem unless they hit the ground or hit something in the water, and if it should happen to me, I would rather be in a heavy displacement, preferably in a steel one.

About your guess between the Swan 46 and 45 : “My guess is that either of the Swan 45s will be much faster, more comfortable and easier to sail too...”

I think that you have guessed wrongly.


In the February 2005 issue of “Yachting World” there is a comparative test between a Swan 46 and a Arcona 460. It is an interesting test because the Arcona (Swedish boat) is a cruiser racer that is very near in type and performance to the Swan 45. Both have narrow fins with a bulb about 8ft draft. the Swan is even more radical with a little bit more sail to the same displacement.

The guy that tested both boats in similar sea conditions (17 to 20 knots of wind) defines the boats like that:

“The Swan 46 is no speed machine, but there wasn’t a hint of slamming, just a very gentle, pleasant motion”.

“The Arcona is good fun to helm, an absolute pleasure, giving precise feedback.”

And in the conclusion.

about the Swan:

...”Nautor solidity and thoughtful cruising design are definitively back. She’s rock solid built with careful attention to detail and fantastic looks, and as a boat to take confidently round the world, she’s perfect.”

About the Arcona:

“The Arcona is a different beast all together, and beast is the operative word. With a powerful rig and lightweight construction, she has performance to shame many higher profile race cruisers.
She would be a fantastic boat to own, for cruising and racing...but she might be a bit more of a handful for the average family to cover thousands of miles on.”


About speed, from the test I will say that there is about 1knot (max 1,5) between the average speed of the two boats in the same wind condition.
For racing it is a huge difference, for cruising it will mean that you make it to the Azores in 13 days instead of 12.
It is not this difference in speed that is going to take you away of trouble if you find bad weather coming towards you.

For that you will need this:

http://www.trimax-europe.com/

Isn’t she a beauty? With one of those I believe you will make it in half the time. Only with one of those things it is true that you will need half the stuff (water, diesel, food) that you need with the other two.

Perhaps I am not too old to have one of those, or maybe I am still crazy after all these years, who knows?

About the Trimax. The boat with 3knots of wind will do 4 knots.

Magic, isn’t it?

Paulo
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