# Boat Overturn



## Val5225 (Oct 26, 2010)

Please, what max angle can accept Catalina 30 before overturn or/and what max wind is still safe for Catalina 30?


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## mpickering (Jun 11, 2010)

The top of the mast would have to be in the water for there to be a threat of the boat capsizing. A lot depends on wind and wave conditions but the boat would have to be on its side first.

As to maximum wind, like any sailboat it is a matter of reducing sail area as windspeed increases. Theoretically, a C-30 like any other 30 footer, could survive hurricane force winds properly sailed under bare poles (no sail up) or a small storm jib/storm trysail. The key words are "properly sailed".

Are you planning to sail into gale or hurricane force conditions anytime soon? Generally, you will want to start reducing sail area by reefing or going to smaller sails when you start to feel uncomfortable or the boat is heeling over excessively and you're fighting the helm to keep her moving in a straight line. Reducing sail will reduce weather helm and make the boat easier to handle as wind speed rises.

Although I don't own a C-30, you should be safe under 25 knots of wind provided you feel comfortable sailing in those conditions and have reefed your sails appropriately. I doubt you'd be safe sailing into that wind with the main fully up and a large overlapping 150% genoa. The boat will be way overpowered, be placing excessive strain on the rigging and you'll be fighting her. With one or two reefs in the main and the jib reduced, you would be able to sail.

Matt


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## PCP (Dec 1, 2004)

mpickering said:


> The top of the mast would have to be in the water for there to be a threat of the boat capsizing. A lot depends on wind and wave conditions but the boat would have to be on its side first.
> 
> As to maximum wind, like any sailboat it is a matter of reducing sail area as windspeed increases. Theoretically, a C-30 like any other 30 footer, could survive hurricane force winds properly sailed under bare poles (no sail up) or a small storm jib/storm trysail. The key words are "properly sailed".
> 
> ..Matt


Matt,

Hurricane force seas cause big seas. A 30ft boat like the Catalina would be easily capsized by a relatively small breaking wave. Any 10ft breaking wave would do the job, sails up or not.

Regards

Paulo


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## swadiver (Jan 17, 2007)

Val,

Namaste is a Catalina 30 Tall Rig. I have two reef points in the main and my headsail is a 150 Genoa on a furler that is capable of furling to reduce the forward sail area. I usually start thinking about putting the first reef in at 15-16 knots. I will try to use the traveller to help de-power the main. However, there is only so much you can do. At 20 knots the first reef should be in for sure. At 25 knots the second reef goes in. I also would furl the genoa to balance the boat when the mainsail reef is put in.


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## Boasun (Feb 10, 2007)

We've knocked a swing keel Catalina 25 down to were the mast spreaders were in the water. She came right back up. So I figure you can do the same with a '30. But if you don't have everything stowed away you will have a total mess in the cabin.
Remember if you are not using it, that item is to be secured for sea at all times.


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## swadiver (Jan 17, 2007)

Val,

Just read the other part of your question. I consider a Catalina 30 a Coastal Cruising boat. I would never consider taking Namaste out in 30+ knot wind. This boat is not a Blue water boat. At 25-30 knots I heard for the slip or someplace to hide. Of course, my sailing area is Southern Calif. and the winds here are usually considered light most of the time. I have had Namaste's rail in the water before and felt comfortable. However, I would not make a habit out of it.


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## sailingdog (Mar 19, 2006)

Generally, for a boat to be capsized the breaking wave has to be 40% of the LOA of the boat.  A 10' wave would probably not capsize a 30' boat but it would make it really uncomfortable...


PCP said:


> Matt,
> 
> Hurricane force seas cause big seas. A 30ft boat like the Catalina would be easily capsized by a relatively small breaking wave. Any 10ft breaking wave would do the job, sails up or not.
> 
> ...


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## chrisncate (Jan 29, 2010)

I bet you could heave to in large seas with a storm anchor at an angle either off the stern or off the bow (for balance) in Catalina 30, and create the same slick that kills breaking waves on more ocean worthy vessels.


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## jephotog (Feb 25, 2002)

I have been out in a C30 in some pretty big wind. Given the right sails (not roller furling) and crew experience it can handle quite a bit. I think sea height and state may be a big contributor to how comfortable it is.


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## PCP (Dec 1, 2004)

sailingdog said:


> Generally, for a boat to be capsized the breaking wave has to be 40% of the LOA of the boat.  A 10' wave would probably not capsize a 30' boat but it would make it really uncomfortable...


Andrew Claughton, the biggest authority on the matter says (on Yacht stability in breaking waves):

"No hull, no combination of ballast, gives an effective resistance to being rolled from a breaking wave with 55% of the yacht length. All the Yachts ca be capsized till 130º by a breaking wave with 35% of the yacht length."

(I am translating from Spanish)

This means that a 30ft boat with the hull shape and ballast ratio of a Contessa (there was one of those among the tested models) will be capsized till 130º by a 10.5ft wave.

The last time I had looked at a Catalina stability curve, it showed a LPS well below 120º, and that means that a 30ft Catalina will be rolled by a 10.5ft breaking wave.

Now, do you really believe that a similar Contessa boat with 30ft, a much more heavier and with a lot more ballast, that will be capsized by a 10.5ft boat, cannot just resist a little bit more (regarding the size of the wave capable to capsize it) than a 30ft Catalina? Not even a wave just 0,5ft bigger?

Of course, if you want to test that, be my guest, on Matt's boat

I would bet on the 10ft breaking wave

Regards

Paulo


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## christyleigh (Dec 17, 2001)

Boasun said:


> We've knocked a swing keel Catalina 25 down to were the mast spreaders were in the water. She came right back up. So I figure you can do the same with a '30.


 You're comparing Apples to Oranges here. They may both be Catalinas but the 25 swing keel is 1000 lbs at the most while the fixed (they all are) C30 is at least 4000 lbs. No comparison in stiffness or ability to withstand wind, waves, etc.....


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## PCP (Dec 1, 2004)

christyleigh said:


> You're comparing Apples to Oranges here. They may both be Catalinas but the 25 swing keel is 1000 lbs at the most while the fixed (they all are) C30 is at least 4000 lbs. No comparison in stiffness or ability to withstand wind, waves, etc.....


That is not the way designers work out the boats. I do not know this particular example, but what is normal is that the same boat with a fixed keel and swing keel would have similar LPS points and a similar stability curve. What the designers do is to put the weight that it is down on a fixed keel (and more) inside the boat, or immediately under the hull, in the box where the swing keel enters..

What normally happens is that a swing keel boat has to have more ballast, to compensate the upper position where it is put, therefore being a slower boat (he can not carry more sale because the stability is the same).

A well designed swinging keel boat (or a centerboarder) can have some advantages over a keel boat on really bad weather because when they are caught by a breaker they can transform the kinetic energy on a lateral gliding movement, when a keel boat would trip on the keel and would transform that energy in a rolling motion.

That's one of the reasons why the French OVNIS, that have a worse stability curve than most of cruising fixed keel boats are good and proven bluewater seaworthy boats.

Regards

Paulo


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## captbillc (Jul 31, 2008)

while this discussion is going on i would like your thoughts on my 30 nimble express. LOA 30.9 LOD 29.11 LWL 25.8 Beam 9.4 Draft 4.6 Displacement 6,500 Ballast 2,700 Ballast/ Displacement Ratio: 42% Displacement/ Length Ratio: 172 Sail Area: 461 Sail Area/ Displacement Ratio: 21


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## christyleigh (Dec 17, 2001)

PCP said:


> That is not the way designers work out the boats. I do not know this particular example, but what is normal is that the same boat with a fixed keel and swing keel would have similar LPS points and a similar stability curve. What the designers do is to put the weight that it is down on a fixed keel (and more) inside the boat, or immediately under the hull, in the box where the swing keel enters.. What normally happens is that a swing keel boat has to have more ballast


 The key phrase in your post is "I do not know this particular example" because it makes all the rest of your post only academic in swing vs fixed keel designs which is good but has little to do with the original post about c25 vs c30 or my reply.

The c25 swing keel is built to be trailerable first and foremost. The older versions had a 1000 lb swing keel for balast (and that's all) and the newer versions are Water Balasted with a light swing keel. As I said your post is a very good academic insight to the way larger ocean going swing vs fixed are designed but the c25 vs c30 is a totally different discussion because they are quite different boats for different markets not really made to compete with each other. The c25 would already be at the dock or on the trailer when the c30 would be coastal cruising and commenting about how the wind and waves had picked up and that some reefing would be in order.


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## stuartmartell (Oct 20, 2004)

*back to the original question*

I have sailed my 1994 c30MKIII tall rig fin keel in winds of steady 35 gusting to 42 true wind during a 100 miler race on Green Bay of Lake michigan. we were close reaching with one reef in the main and a partialy furled 150 genoa. We were of course "rail down " but the boat was steady as a rock, pounding into large waves at hull speed. After that experience I trust my boat completely.
BTW I won't do it again on purpose!
Stu


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## PCP (Dec 1, 2004)

christyleigh said:


> The key phrase in your post is "I do not know this particular example" because it makes all the rest of your post only academic in swing vs fixed keel designs which is good but has little to do with the original post about c25 vs c30 or my reply.
> 
> The c25 swing keel is built to be trailerable first and foremost. The older versions had a 1000 lb swing keel for balast (and that's all) and the newer versions are Water Balasted with a light swing keel. As I said your post is a very good academic insight to the way larger ocean going swing vs fixed are designed but the c25 vs c30 is a totally different discussion because they are quite different boats for different markets not really made to compete with each other. The c25 would already be at the dock or on the trailer when the c30 would be coastal cruising and commenting about how the wind and waves had picked up and that some reefing would be in order.


Sorry, you are right. I was not being academic, what I wrote is true but I missed that you were talking about two different boats and *not about a Catalina 30 with two keel versions (a swing one and a deep one)*. My bad


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## PCP (Dec 1, 2004)

captbillc said:


> while this discussion is going on i would like your thoughts on my 30 nimble express. LOA 30.9 LOD 29.11 LWL 25.8 Beam 9.4 Draft 4.6 Displacement 6,500 Ballast 2,700 Ballast/ Displacement Ratio: 42% Displacement/ Length Ratio: 172 Sail Area: 461 Sail Area/ Displacement Ratio: 21


I don't know much about older boats and even less about older American boats, but I was curious and I had a look....and I was surprised:

The boat is a classic and very beautiful boat, with a gorgeous interior. It looks a bit like a Frances, but it has a more modern hull, with a fin keel and what appears to be a good compromise rudder with a little skeg.

Nimble 30

I thought that there was a mistake about the weight till I saw the tech file: This boat has a MODERN construction and uses expensive and light materials.

It has also a high B/D ratio, even if I think that the one you gave me is the one from the centerboarder version. The deeper keel, that has only 1.2M has a B/D of 37%. It seems that its lead ballast and a very light hull permits this boat to carry a lot of sail and more than compensates the bulbed longer keel of a modern 30ft cruising boat (with slightly less ballast, but a more a heavy hull).

If we compare it with a Jeanneau 30, your boat will be probably faster in very light winds (I find that amazing), it will have probably a better AVS and a smaller inverted stability, but will be slower in winds over 10 K and a lot slower with strong winds. That's because your boat will have a remarkably smaller LWL (by design) and therefore a smaller hull speed but also will not plane (displacement hull), while the jeanneau will have a semi-planning hull. On other hand your boat will be more comfortable in steep seas, against the wind. The Jeanneau will also point better to the wind (much bigger keel).

For a classic boat your boat is really a fast one. It carries almost the same sail as the Jeanneau and it is remarkably lighter.

Caracteristiques Techniques - Jeanneau Yard

http://anciensbateaux.jeanneau.fr/inventaire/inventaire_2_20091203_INV_SO30i-SO33i_GB_11-09.pdf

I don't know about the construction quality, but judging by the enthusiastic owners, it seems to be good or very good and that would make this pretty exclusive boat (26?) a delightful boat to own that should make any owner proud.

Regards

Paulo


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## christyleigh (Dec 17, 2001)

PCP said:


> I was not being academic, what I wrote is true


Sorry if you took my meaning of "academic" as some form of an insult or that you were not right in what you were saying. I simply meant that you were giving some technical information about an Apples vs Apples - swing vs fixed boat that because, as you realized - wasn't the case, it just became academic.... as in a teacher giving a lecture. Nothing wrong with that  My use of the word, although fairly common, may not be in any dictionary as the 'definition of the word'.....


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## hellosailor (Apr 11, 2006)

Val, you will find a Capsize Screening Calculator and a capsize angel link about midway down this page:

Sailboat Design and Stability

Note that calculations are often not exactly matching a boat but if you are asking in order to find out if the boat can qualify to meet a national regulation, these are the formulas you would start with.


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## AdamLein (Nov 6, 2007)

Something tells me that conditions involving hurricane force winds and 10-foot breaking seas are not what the OP reasonably expects to encounter. I would guess, from his question, that he's either thinking about buying a boat and wants to know whether the C-30 is reasonably safe, or has just bought a C-30 and wants to know how safe it is.

So in answer to that: if you have two people to handle the boat, you should be fine in winds up to 35 knots. Beyond that you should think about staying at the dock, not because of imminent danger of capsize, but more because the boat will be more difficult to handle and there's a greater danger of other things going wrong, such as damage to your sails or rigging and the possibility of a man-overboard situation. If you're sailing alone you've got a lot more work to do, more time spent on deck, etc., so I would not want to be out in more than 25 knots, though even 20 is going to be a good day's work.

Stick to such conditions and voila, your boat will not capsize under any circumstances.


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## tomandchris (Nov 11, 2009)

Agree with Adam. I have been out in over 35 with a C30, solo, and it was not fun. However, at no time was I worried that I was going to roll her. That boat would take a lot more than I would. Just reef and sail.

That being said, what kind of a hurricane only has 10 footers? Lake Michigan at the moment has 20 footers at 7 second intervals,and it is only blowing in the 40's. The freighters are hiding behind land in all the bays. The only thing still out there are the 1000 footers, and most of them are hiding as well.Weather coming to the east coast soon.


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