Advantages of a multihull sailboat

[MidLandOne]

Originally Posted by rickm505

These conditions are just too much for any cruising sail boat to attempt sailing or manuvering. No monohull could be prevented from broaching and rolling regardless of the experience of the crews or strategies employed. This is why all of them were dismasted.

Rick - you are definitely getting carried away with yerself - using the estimates at the time of the total fleet numbers, around 45 monohulls completed their voyage intact. They did not all get dismasted - maybe that is not what you meant, but that is what you wrote.

Regarding your comment on crew competency being of no effect - I will send you a PM regarding the situation for your own information.

[Talbot]

Originally Posted by Pelagic

Are there many 30 year old, well used Cats that have demonstrated long term structural integrity?

That could be a factor to consider when choosing.

The very first fibreglass cats were pretty new 30 years ago. There are still numerous catalacs from that era that a very tired inside, but still structually sound. It does not take a great deal of effort to bring them back up to a decent standard (upholstery, headlining re-wire, instruments yes, possible a new set of mast and rigging and engine)

[Southern Star]

And Pelagic, despite the gelcoat repairs you observed on some older Prouts, they too have proven to be remarkably strong. Many older monohulls also display some gelcoat cracks at sharp curves by the house, etc. Is an older Prout as strong as your steel boat? Of course not (and as a previous owner of a steel boat, I fully appreciate the structural advantages to steel). Nevertheless, there are many 30 year old Prouts, Catalacs, Cherokees etc. that have shown no adverse effect from years at sea. Indeed, the typical Lloyd's scantlings, while considered overkill by some on a cat, have proven their worth over time.

Brad

[Pelagic]

Good to know....Thanks!

[Tropic Cat]

I believe there are many sailors who choose monohulls for purely esthetic and historical reasons. Monos are the traditional European sailing vessel and admittedly gorgeous while under sail. We all can appreciate this. Heeling is a part of the esthetic for them. Many of today’s modern catamarans are just not that attractive and of course, they lack that certain romance.

It isn't until logic is injected into the equation that the benefits of a multihull are appreciated. However, when it is, catamarans win, hands down. We all can agree that their acceptance has improved greatly in the last decade and if somehow there were a reduction of their price tag, it would be more so.

[Tropic Cat]

Originally Posted by MidLandOne

Rick - you are definitely getting carried away with yerself - using the estimates at the time of the total fleet numbers, around 45 monohulls completed their voyage intact. They did not all get dismasted - maybe that is not what you meant, but that is what you wrote.

Regarding your comment on crew competency being of no effect - I will send you a PM regarding the situation for your own information.

Thanks,

With regard to my comments. I'm referencing the center of the storm, not the periphery where conditions were more benign.

[Eleven]

Good to hear Prouts are still viable 'Cruisers'.
I did see else where that sunlight seriously affects GRP taking about ten per cent of strength out of a (boat?) in ten years.
Tribute to the Prout (AND OTHERS) build and a caution to a buyer. If the hulls and their connections look tired they probably are. Get a survey, don't go on the manufacturers reputation.
Re: Crew v boat in Bad weather. It is up to the crew to put the boat into survival mode. Then leave it be. Mono's broached, were they on bow on stern drag devices?
Some will want to hand steer through it all, but for three days, in extremes. Each boat must have a safe mode on board before going blue.
I understand the Aussie to NZ is very variable weather wise. The seamans rule still applies that boat and crew must be fit for more than they expect if nerves are not going to be shredded (and the boat sold or sunk). Redundancy plays a factor. One skipper can be out of action or overboard. Who takes up the responsibility?

[Woods Designs]

Several postings have said "get a Survey" but be warned. Not all surveyors know anything about multihulls. One once asked me how much ballast there was in the LAR keels. So use as much due dilligence in choosing a surveyor as you would when choosing the boat.

For Eleven's benefit. I'd use Rob Feloy if I was buying a boat (any number of hulls) in the UK

Richard Woods of Woods Designs

Woods Designs Sailing Catamarans

[GordMay]

Further to Long-Term Structural Integrity:

Excerpted from:
The design of a 52ft. Aerorig cruising catamaran
by John Shuttleworth
Goto:
Design of a 52ft. Aerorig catamaran.

<quote>
Construction and fatigue:

During the lifespan of a multihull it is subjected to many cycles of a complex array of loads, and if the boat is to survive in all conditions without damage careful attention has to be paid to avoiding stress concentrations in the structure, and to the long term fatigue of the materials used to build it. By using a computer to analyze the loads at any point in the boat, and then laying appropriate amounts of fibers aligned in the direction of the stress, the stiffness and the strength of the boat can be greatly increased. While at the same time weight can be saved by removing excess material where it is not required. This weight saving actually increases the strength of the boat, because it not only reduces the loads that the boat experiences, but it reduces stress concentrations, which are a major cause of fatigue failure. I have called this technique of designing integrated structure. ( ref. 4) If the structural design is carried out in this way, and adequate allowance is made in the fiber stress levels in the all parts of the boat to account for long term fatigue, the lifespan of the boat will be greatly increased.

At present, research indicates that if a composite laminate can survive over 10 million cycles, it will last indefinitely. In general in order to achieve this, a factor of safety of at least 10 is required. In all my cruising designs I use at least 10 as a factor of safety in areas of maximum stress. For carbon in particular the laminate is strain limited because the material is so stiff, has a relatively low strain to failure, and an extremely high notch sensitivity. However the material can be very successfully used in areas where great stiffness is required, like the cross beams of a multihull.
<end quote>

[Joli]

Rick, your facts are only your opinion. For every benefit you claim I can see a negative (IE pro: doesn't heel, con: very short motion or pro: reaching speed, con: limited upwind ability)

We can go on and on but why? The world of boating is a world of compromise, we all make our own decisions based on our wants and needs.

Honestly I find these types of thread titles divisive.

Originally Posted by rickm505

It isn't until logic is injected into the equation that the benefits of a multihull are appreciated. However, when it is, catamarans win, hands down. .

[Tropic Cat]

Originally Posted by Joli

Rick, your facts are only your opinion. For every benefit you claim I can see a negative.

This doesn't exactly come as a big surprise. Different year, same opinions.. but I am curious ... which facts did I post that you disagree with?

[imagine2frolic]

[quote=rickm505;209155]I believe there are many sailors who choose monohulls for purely esthetic and historical reasons. Monos are the traditional European sailing vessel and admittedly gorgeous while under sail. We all can appreciate this. Heeling is a part of the esthetic for them. Many of today’s modern catamarans are just not that attractive and of course, they lack that certain romance.

I can appreciate your comment for the mono. When I think of a salon I think of beautiful dark wood, and portholes for light.

I do find a catamaran to be extremely capable of bringing romance to sailing. I myself being part Hawaiian can imagine myself as my ancestors exploring the ocean. Of course on a warm night when out of sight of land it is enhanced. Then again my imagination has been known to run wild!!!!!!!!

[Woods Designs]

At the risk of being called pedantic, this is what the first post said.

Originally Posted by jotra76

What are the advantages of a multihull sailboat that monohull sailboats dont have monohull sailboats and vice versa

Jotra didn't want to know about the disadvantages of monohulls or multihulls. Maybe its time to start (yet another) thread that deals with the disadvantages of different types of vessel

Just a thought

Richard Woods of Woods Designs

www.sailingcatamarans.com

[Joli]

And there is the crux....you may define a characteristic as an advantage whereas others see it as a disadvantage. This is a circular argument that only leads to divisiveness.

Originally Posted by Woods Designs

At the risk of being called pedantic, this is what the first post said.


Jotra didn't want to know about the disadvantages of monohulls or multihulls. Maybe its time to start (yet another) thread that deals with the disadvantages of different types of vessel

Just a thought

Richard Woods of Woods Designs

www.sailingcatamarans.com

[Tnflakbait]

Haha,

I feel like this same thread is created and played out every couple of months or so! Oh well.. that's what forums are for!