Modern cats

[Factor]

Originally Posted by Polux

Yes weight is your friend in what regards capsizing risk on a cat. .

No it isn't.

[44'cruisingcat]

Originally Posted by Polux

Yes weight is your friend in what regards capsizing risk on a cat. Weight counts two times for stability, beam one.

There's more to it than just weight.
You could have a light boat with a small rig, and a heavy boat with a huge rig.
A light boat with large beam, a heavy one that is narrower.

[Polux]

Originally Posted by 44'cruisingcat

There's more to it than just weight.
You could have a light boat with a small rig, and a heavy boat with a huge rig.
A light boat with large beam, a heavy one that is narrower.

As you know performance cats have proportionally bigger rig (SA/D) than heavy condo cats, so that is also a factor that contributes to a bigger capsize risk between the two types.

In what regards beam it counts only 1 time for stability while weight counts 2.

Yes you have some heavy cats with a smaller beam proportion but they are mostly old designs. Today modern condo cats have a beam that is not very different than the one from performance cats. Beam just goes well with the concept of condo cat: more beam, bigger interior space.

[InTheDish]

There is nothing so fine as a finely tuned performance boat nearing her boundaries in the right conditions....I just love it.

There is nothing so fine as my wife. I love her company and have purchased a floating condo.

One makes their choices in this grand life of ours.

[mikereed100]

Originally Posted by Polux

For me sail and sail pleasure are at least as important as cruising. Even if the place where I am at anchor (90% of the days) is very beautiful I never stay more than 2 days (my wife hates that) for the simple reason that I want to sail and two days is about limit I find tolerable without sailing.

Spoken like a future singlehander. You might do well to pay more attention to what your wife likes. Which is kind of the crux of this thread. Until recent decades boats were sleek, beautiful, spartan and almost completely free of female crew. Boats are bigger and more comfortable now, at the expense of some performance to be sure, but the company is far more pleasant.

[44'cruisingcat]

Originally Posted by Polux

As you know performance cats have proportionally bigger rig (SA/D) than heavy condo cats, so that is also a factor that contributes to a bigger capsize risk between the two types.

In what regards beam it counts only 1 time for stability while weight counts 2..

Not necessarily. Some boats are easily driven and have correspondingly conservative rigs.

So 1kg of weight equals 2 metres of beam? Is this some "rule" you've invented? Beam and weight are different properties, measured in different units. What you're saying is like saying sunshine counts twice as much as music. It's meaningless.

[matt w]

Originally Posted by daletournier

The more comfortable we are the longer we are likely to cruise IMO, Ive heard people call my boat a performance cruiser but its all relative as it wouldn't stand a chance against Polux's boat or Cc44's, yet around the condo cats shes reasonably fast even fully loaded, but "fast sailing" is an oxymoron, i think I'm flying at 8.5k..lol.

Mine could be called a Condo mono i suppose...lol. It has seven foot headroom , microwave and I'll be adding a washing machine next year, I like a good shower, used 600 liters of water last week, yes pathetic i know!

Cruising for me is moving my home to different places and thats what the sails are for, the enjoyment from the sailing is secondary although i must admit I'm really enjoying the sailing in flat water clear waters of the Seychelles, small hops just the way i like it.

Condocats are popular and will become more popular for good reason, they are extremely comfortable living, they do sail and you can take them around the world, i witness this...travelling in comfort! why not?

Definitions get messy, trying to pidgeon hole boats and people never works. Im lucky im not a sailor ,can't get offended when people recognize im just not that salty.

Dale, what boat do you have that has seven feet of headroom?

[daletournier]

Originally Posted by matt w

Dale, what boat do you have that has seven feet of headroom?

Hi Matt, i have a Catalina 470. I just got the measuring tape out to make sure i wasnt fibbing. 7.2 feet or 2.2m.
Im not that tall but it definately adds to the feeling of "space" in the boat.
Closing hatchs can be an issue.
Unlike a lot of designs it still has a very good bilge as well.

[PhiSig1071]

Being 6'4"+ Headroom in cats is an issue for me. More modern designs seem to have addressed the issue somewhat. The Leopard/Moorings 39 has 6'7" of headroom in the galley, at the tallest point in the saloon, and in the hulls by the beds. Apparently it slopes to about 6'3" at the head of the saloon and in the shower stall on the owners version. That does equate to a lot of freeboard, both to get the headroom in the hulls and to balance the high bridgedeck roofline on a relatively short boat.

[44'cruisingcat]

Originally Posted by daletournier

Hi Matt, i have a Catalina 470. I just got the measuring tape out to make sure i wasnt fibbing. 7.2 feet or 2.2m.
Im not that tall but it definately adds to the feeling of "space" in the boat.
Closing hatchs can be an issue.
Unlike a lot of designs it still has a very good bilge as well.

We have about 7' headroom.

[Polux]

Originally Posted by mikereed100

Spoken like a future singlehander. You might do well to pay more attention to what your wife likes. Which is kind of the crux of this thread. Until recent decades boats were sleek, beautiful, spartan and almost completely free of female crew. Boats are bigger and more comfortable now, at the expense of some performance to be sure, but the company is far more pleasant.

In fact I single hand the boat 90% of the time. 2 days on a place is already a compromise. What I like is to pass 1 day on a place if it is a nice one, otherwise I like to arrive in the afternoon and to sail out in the morning.

[Polux]

Posted by Polux: "As you know performance cats have proportionally bigger rig (SA/D) than heavy condo cats, so that is also a factor that contributes to a bigger capsize risk between the two types. "

Originally Posted by 44'cruisingcat

Not necessarily. Some boats are easily driven and have correspondingly conservative rigs.
...

I don't know if you make it express or out of ignorance but you are misleading people that think you know a lot about cats.

As I hope you now, the Sail area/displacement measures the proportion of sail area to the displacement of a sailing boat. The higher the number the bigger a proportion of sail to a given displacement.

On a catamarans case, assuming the same beam that means that the boat with the bigger SA/D takes more risks regarding capsizing.

To see if you are correct, lets look at the SA/D numbers of the more popular performance cats and condo cats, namely Outremer and Catana on one side and Lagoon and Fountain Pajot on the other (all current models).

Outremer 45 SA/D - 25.5;....Catana 47 SA/D - 28.8

Lagoon 450 SA/D - 22.0;....FP47 SA/D - 22.4; FP44 SA/D - 23.9

As you can see and as I had said, performance boats, being them catamarans or monohulls have a bigger SA/D than condo boats, more sail area for the same displacement.

That was if the beam was the same (the capsizing risk) but in fact the Lagoon 450 is beamier than the Outremer 45 and the FP 47 (Saona) is slightly beamier than the Catana 47 so that just increases more, particularly on the Lagoon the capacity to resist a capsize.

But this is considering SA/D, considering the sail area as a parameter for the boat overall stability and capsize resistance and that is a thing that I don't like because that assumes the boats will always sail flying all the sail area and that is not obviously not true because all those boats can be reefed.

Even if the Sail area versus total stability is an important factor (mostly for irresponsible or ignorant sailors that don't use the right amount of sail to the conditions) the overall resistance to a capsize is also a very important one, assuming the boat is reefed or even in bare poles.

Regarding the overall resistance to capsize the diference between those performance catamarans and the condocats is simply huge. Lets look at the Outremer 45 and the Lagoon 450: the Outremer beam is 23.3ft, the Lagoon has 25.6ft (more beam more stability) but more important than that diference is the diference in weight since the Lagoon is 78% heavier....and as weight counts two times for stability you can see that the Lagoon is way more than two times harder to capsize than the Outremer 45.

These are the numbers that show why we have seen on the last years several big performance cruising Catamarans capsizing on gusts while we had not seen any condocat capsizing due to that.

[smj]

Originally Posted by Polux

Posted by Polux: "As you know performance cats have proportionally bigger rig (SA/D) than heavy condo cats, so that is also a factor that contributes to a bigger capsize risk between the two types. "



I don't know if you make it express or out of ignorance but you are misleading people that think you know a lot about cats.

As I hope you now, the Sail area/displacement measures the proportion of sail area to the displacement of a sailing boat. The higher the number the bigger a proportion of sail to a given displacement.

On a catamarans case, assuming the same beam that means that the boat with the bigger SA/D takes more risks regarding capsizing.

To see if you are correct, lets look at the SA/D numbers of the more popular performance cats and condo cats, namely Outremer and Catana on one side and Lagoon and Fountain Pajot on the other (all current models).

Outremer 45 SA/D - 25.5;....Catana 47 SA/D - 28.8

Lagoon 450 SA/D - 22.0;....FP47 SA/D - 22.4; FP44 SA/D - 23.9

As you can see and as I had said, performance boats, being them catamarans or monohulls have a bigger SA/D than condo boats, more sail area for the same displacement.

That was if the beam was the same (the capsizing risk) but in fact the Lagoon 450 is beamier than the Outremer 45 and the FP 47 (Saona) is slightly beamier than the Catana 47 so that just increases more, particularly on the Lagoon the capacity to resist a capsize.

But this is considering SA/D, considering the sail area as a parameter for the boat overall stability and capsize resistance and that is a thing that I don't like because that assumes the boats will always sail flying all the sail area and that is not obviously not true because all those boats can be reefed.

Even if the Sail area versus total stability is an important factor (mostly for irresponsible or ignorant sailors that don't use the right amount of sail to the conditions) the overall resistance to a capsize is also a very important one, assuming the boat is reefed or even in bare poles.

Regarding the overall resistance to capsize the diference between those performance catamarans and the condocats is simply huge. Lets look at the Outremer 45 and the Lagoon 450: the Outremer beam is 23.3ft, the Lagoon has 25.6ft (more beam more stability) but more important than that diference is the diference in weight since the Lagoon is 78% heavier....and as weight counts two times for stability you can see that the Lagoon is way more than two times harder to capsize than the Outremer 45.

These are the numbers that show why we have seen on the last years several big performance cruising Catamarans capsizing on gusts while we had not seen any condocat capsizing due to that.

The stability speed of the Lagoon 450 is 25.5
The stability speed of the Outremer 45 is 22.74
This means the Outremer will start to raise a hull in a wind 2.76 knots less than the Lagoon.
The Kelsall stability index of the Lagoon 450 is 42.98
The Kelsall stability index of the Outremer 45 is 38.25
This means under full working sail the Outremer will start to capsize in 4.73 kts less wind than the Lagoon 450.
Obviously not a large difference on either.


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[Go Wildcats]

I'm no expert in this by any means, however, I would think that the beam, bridge deck clearance, among other physical characteristics play a part in the likelihood of capsizing, not just SA/D. I could also see that the boom location (height above the waterline) could play a role. Physics.

[Polux]

Originally Posted by smj

The stability speed of the Lagoon 450 is 25.5
The stability speed of the Outremer 45 is 22.74
This means the Outremer will start to raise a hull in a wind 2.76 knots less than the Lagoon.
The Kelsall stability index of the Lagoon 450 is 42.98
The Kelsall stability index of the Outremer 45 is 38.25
This means under full working sail the Outremer will start to capsize in 4.73 kts less wind than the Lagoon 450.
Obviously not a large difference on either.

Those figures assume full sail and since there is not a huge diference in beam between the two boats as to do with the difference between the SA/D of both boats, 25.5 to the Outremer, 22 to the Lagoon. Those figures don't say nothing about the overall stability of both boats, the energy that is needed to capsize them but refer only to the stability in relation to the full sail area.

The Lagoon has much more sail than the Outremer. Even considering the Lagoon with a Genoa and the Outremer with a jib the diference in sail area is 305 sq ft, between 1/3 and 1/4 of the total sail area of the Outremer.

With the boats reefed the relation between overall stability and sail area will be very different and on normal circumstances, with wind able to capsize the boat both boats will be reffed.

On extreme circumstances, with both boats on bare poles the Lagoon will have more than the double of the stability of the Outremer, meaning that the energy needed to capsize it has to be more than the double of the one needed to capsize the Outremer.

Even so looking at the wind needed to capsize the boat with full sails, 43k is a lot different than 38K, I mean the possibility of finding 43k winds is much smaller that finding 38k winds. That apparent small diference in knots is not proportional to possibility to find one or another wind.