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  #46  
Old 05-08-2009, 07:55 PM
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Fanie Fanie is offline
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Mono's or multi's capsizing seems mostly due to too strong wind and waves, probably a combination of them. Having a clutched cleat that can let the sail out when a certain force on the sail is built up can dump the wind and prevent a capsize.

Not for racers before that one starts again

When your sail gets released some frequently, it should tell you one of two things, either the clutch is adjusted too slack or you are pushing your luck in too strong winds.

Any boat can be made unsinkable. It should be a design cryteria incorporated into the design from the start. All unusable spaces or spaces that does not serve a purpose can add to bouancy. Some boat builders doesn't care a damn, just wants to make money. If someon drowns off'n his boat, tough ****, it's not his problem. It's not like the guy can sue him...

Why can a monohull not be steadied to some extent when lying ahull by adding a sea anchor to it's mast to limit it's roll ? It doesn't have to connect to the top of the mast but some ways down should already have a big effect. I'm also thinking of something like the series sea anchor that has smaller funnels instead of the huge uncontrollable ones. The advantage of the series sea anchor is you can let more or less funnels out to control the drag. Be a bugger if the sea anchor capsize the monohull There should be two ropes, one off the mast and one off the deck.

That said, I don't want to create the idea that I'm a mono hull fan... Yuk

Some like mono's, some like multi's, it keeps the conversation (and discrimination) going but it is personal taste no matter how wrong a monohull is

The biggest factor in most boating accidents is idiotism. The guy that goes out with the wrong boat for the conditions, not taking protective clothing, drink alcohol aboard, no water, speeding, not wearing PFD's, yes they are a pain but if the boat moves wear the darn thing. Neglegence, wreckless, unprepared.

I think most people falling overboard, shock, cold water and gets a drop of water in the airways, cough involutarily while under water, making drowning quickly when water gets swallowed or in the airways.

Boats are very safe things if it wasn't for humans.
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  #47  
Old 05-08-2009, 08:13 PM
Ad Hoc Ad Hoc is offline
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As I said in my first post, it is all about supply and demand!

Everything comes at a price, not everyone is willing to pay for it.....
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  #48  
Old 05-08-2009, 08:19 PM
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Hi Ad Hoc,

Yes you did. It seems we share a common view on that. My one friend bought such a boat. He doesn't say it but I can see he doesn't like what they did with it, and it's not nice going out with it either.

Depending on what you use and how you design it, it doesn't have to cost extra or that much extra. Many designers doesn't bother, as you said, supply and demand. Just get rid of it asap.
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  #49  
Old 05-08-2009, 09:58 PM
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another reason Ill be building and not buying
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  #50  
Old 05-08-2009, 10:02 PM
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Fanie,

Don't start me on boat use. Look at any Marina,, anywhere, most boats are tied up all day every day....there are very few people that actually USE their boats.
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  #51  
Old 05-09-2009, 06:28 AM
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Yes well, the one marina owner told me they don't mind, they get paid for doing nothing. Probably a good thing, imagine 90% of them going out the same day

It is a comforting thought to know your boat cannot sink even when it gets swamped.
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  #52  
Old 05-12-2009, 07:47 AM
bad dog bad dog is offline
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Somewhere back up this thread there was a comment about whether the rig would survive the capsize (sorry can't remember who posed the question, I have been unavoidably detained by work).

I have seen plenty of pics of the balls-out ORMA 60s capsized - hopefully this post includes one (never tried this before). My experience - limited admittedly at larger scale - is that capsizes happen somewhat slowly. Certainly a lot of the initial velocity is washed off as the sail loses wind and drive.



But note that the mast is holding the boat up for some time after the initial flip.

The other comments I would absolutely support are that a seagoing cat should have high bridgedeck clearance, and a robust access hatch to it from a secure part of one hull. I had the pleasure of sailing on Lock Crowther's 48' Deguello for some years. Bit of a handful racing round the cans in Pittwater, but at sea, it was in its element - as Lock had designed it for two handed ocean racing. High bridgedeck, access hatch and bright orange non-skid underneath spelt preparedness. I wish I had done more ocean miles, but that's another story (carpe deum, die with no regrets - all that sort of gung ho stuff!).
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  #53  
Old 05-12-2009, 07:52 AM
bad dog bad dog is offline
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image embedded this time...

...I think. Getting cleverer at this. Maybe.
Attached Thumbnails
Sink or Swim??-multicup-chavirage-de-banque-populaire-614-h-75-550.jpg  
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  #54  
Old 05-17-2009, 05:52 PM
ancient kayaker ancient kayaker is offline
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Interesting discussion. Mostly it seems to be about larger sail boats; at the other end of the scale different factors come into play. As with road vehicles, size has an impact on the nature of accidents.

Perhaps I can benefit from your experience. I am just starting to build a car-top sized sailboat, as a fairly cautious individual I don't expect to get into trouble but I plan for it. The most likely problems I can see during a day sail is 1) a fast-moving stinkpot hits me or 2) I push the limits or find a wind knuckle and and flip her. Apart from keeping a lookout and having a noise-maker and supply of shoulder-mounted missiles I don't see being able to doing much to avoid #1, but hopefully I can survive it by wearing a PFD.

As a paddler, so far, I have found wearing a PFD makes wet entry more difficult. The trick is planning ahead, having an inflatable bladder to put on one end of the paddle, a velcro tie on the thwart to attach the other end of the paddle, and a loop of rope from the thwart for my foot. Having converted the canoe to a temporary catamaran, re-entry is a snap provided the boat has been bailed, which is fairly easy to do with a lightweight canoe (just jerk the hull out from underneath the water). All that works on a long, narrow 20 lb boat, but not all of that may translate to a heavier short, beamy one.

Getting back to #2 I would need to right the boat, re-enter, bail and resume sailing before someone motors up to help and clips me on the head with the prop . I'm closing on 70 with several of the customary ailments associated therewith, an important consideration. My thoughts are: a buoyant mast so she doesn't turn turtle; a rope ladder or loop over the transom to aid re-entry, a buoyancy tank along each side big enough to support the entire weight of the boat so she comes up more-or-less dry, and it would be really nice if she didn't sail off into the sunset in a sprightly manner leaving me behind, so a leash for either me or the boat, depending on your point of view ...

In a wet entry with a small light boat, the boat probably wants to sit on top of the person rather than the other way round. I suspect getting into a boat from the water unaided, even into a dry boat, involves some non-existent athletic ability and a helpful tip or two. If the side buoyancy tanks are big enough I am thinking that I can climb on top of a tank while the boat is on her side and use my own weight and an oar to bring her upright, kind of a variant on self-righting, although I do worry about the effect of that sail-full of water.

Do any caveats or suggestions spring to mind on the above?
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  #55  
Old 05-27-2009, 03:40 AM
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I found this interesting...



Stretching "self righting" more than a little, but it works...
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  #56  
Old 05-27-2009, 07:03 AM
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Nice post there Zed -

However, it is great for smaller boats where there is not a lot of stuff in it.

If you plan to overnight aboard with all the stuff you take along, even if you can right the boat, imagine what a mess it's going to be And especially the wiemen will be hugely impressed by a capsize.

While the weather and water is mild, it will be ok, despite the initial mess. Doing simple things in bad weather usually becomes a bit more complicated, and from experience I can tell you under the cover of darkness a whole new set of rules comes to play.
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  #57  
Old 05-27-2009, 07:16 AM
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Yeah, only an exercise to undertake on a glorified Hobie! Nothing you really want to do undertake in anything else, but then again rolling a mono is to be avoided! I'm just impressed that it can be done, albeit with a little setup, notice that the boats mast was pulled around to weather so that the wind pushed on the tramp and helped the whole process!

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  #58  
Old 05-27-2009, 08:16 AM
bad dog bad dog is offline
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Thanks for digging that up - look at the speed sailing clip as well, very impressive boat.

It has a lot of the features of my old Catapult (now in Qld with Mike Moran at Humpybong YC): canting rig, variable raking rig, all make for better sail trimming than a fixed mast, plus all the righting advantages. It had an 8:1 on the shrouds directly, whereas this Firebird thingy uses the tangential tweakers on the running backstays, which is not as radical but much easier. If you let them off before the point of no return, it is a quick dump and drop. See chttp://www.catapultcats.com/ - although the website doesn't show much of how they work.
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  #59  
Old 05-28-2009, 02:02 AM
ThomD ThomD is offline
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I am somewhat stunned that this crap would be discussed at all in '09, let alone in a multihull design forum. Obviously it is better to capsize than to sink and monos can in any case do both. But the discussion seems to me to be toweringly irrelevant. As Jim Brown said, more, elegantly than I can remember, rational arguments are just what we call on to justify our emotional preferences. As Richard pointed out, as long as they think they look good, folks are happy to cruise around on choppers without wearing helmets. People fall in love with monos, or multis, and if they have the guts to take them offshore at all, the marginal difference in survivability of one design type vs. another is a towering irrelevance. If you looked at that marginal difference how would it compare to other choices we routinely make about, boat model; crew/experience; boat size; cruising grounds; emergency gear; training; etc...

The most depressing thing is the idea that people who think this kind of discussion/distinction is actually important are captaining boats at all, that may well explain a lot.

Not that it is likely to make anyone sleep any better, but there are two self righting designs of multihulls. One is the G32, which is perfectly able to, in the words of the OSTAR Race Committee, "race along... in between periodically capsizing...". I seem to recall reading a NEMA newsletter about her capsizing several times on the way to a win, I guess she is really more rightable than self-rightable, but may get extra points for not even getting the occupant wet. The other type is the proa, which in the case of the Brown Pacific proa was described to me by Jim Brown as a boat that was self-righting. Cheers?Atlantic proas may have shared that characteristic, she was certainly deemed rightable. Proas share one of the main attributes of self-righting monos: Easy over and easy back up. One proa the Harry, it is claimed, can't be capsized.
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  #60  
Old 05-28-2009, 02:09 AM
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Quote:
The most depressing thing is the idea that people who think this kind of discussion/distinction is actually important are captaining boats at all, that may well explain a lot.
Way to insult everyone who has posted on this thread! I suppose I better go sell the boat now you know being an incompetent idiot and all.
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