Sink or Swim??

Discussion in 'Multihulls' started by Richard Woods, May 5, 2009.

  1. Fanie
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    Fanie Fanie

    I can tell you why mono's aren't made unsinkable. Same reason why you can buy any boat that hasn't changed or improved in ten years or even longer. The builder just wants to make money and bugger the customer. Granted not all builders are like that, but it seems too many here :( Looks like they make too much money too easy.
     
  2. Manie B
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    Manie B Senior Member

    Hey Fanie this is the sink or swim thread :D

    i know you want to hang our local "boat builders" and yes you are right so

    but did you at least look at this crazy **** sailing a mono :D :D :D :D

    http://www.sail-world.com/cruising/index.cfm?nid=57162&rid=11

    what ever he was drinking - i also want some :D :eek: it gives you some serious courage :cool: :p

    another mono that made it -phew thank gawd ;)
     
  3. Fanie
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    Fanie Fanie

    The wife probably told him he better get home right away or else. Only time you see a guy throwing caution to wind and bugger all...
     
  4. Zed
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    Zed Senior Member

    Manie, if you only knew the number of mono's that have rolled on Southport Bar, normally on the inbound trip. I think I'd sooner tackle the bar in a mutli and I am a long time mono sailor. As for the trip out as pictured, in those conditions its all about power and speed, well agility anyway. I am not sure I'd do that any anything that has its engine described as auxiliary. By the way power cats are popular up there.
     
  5. BeauVrolyk
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    BeauVrolyk Sailor

    All,

    I was quite surprised by the tone of this post. There are a number of odd assumptions represented here.

    First, there are lots of monohulls that will not ship water even when the rig is put into the water. This doesn't just include racing boats, but also includes my old cruising ketch, a big steel thing of 65'. When laid on her side with the mast head in the water, the water line was three feet below the hatches. This was an intentional feature of the boat's design, and the reason that most deep water boats have their hatches on the centerline. So, I have to disagree with Bad Dog, as a large number of monohulls would have come up just fine. Moreover, as I understand it the wind velocity did this, not giant waves, so a mono probably wouldn't even have heeled past about 50 or 60 degrees even in 40 knots of wind, unless she was very light and over canvased.

    This brings me to my second point. I live and sail on San Francisco Bay. Two weeks ago we were out racing in our old sloops (IODs built in the 40s and 50s) and the wind was a solid 30 with gusts to 35. We had three or four gusts that were well above 40 knots, as reported by both the StFYC and the US Coast Guard. No one flipped, no one sank, we didn't even stop racing. For those of you who don't know the IOD, it was designed in 1936 and does NOT have a self bailing cockpit. It has no hatch cover or doors to keep water out, and has a relatively large mainsail, which none of us had reefed, we didn't need to.

    As the gusts came through the fleet a number of boats rounded up and went head to wind. Almost all of us heeled over to about 45 or 50 degrees as we spun around, but that was it. No one sank, no mast went in the water, no drama. I don't know what sort of monohulls you guys sail, but if a 1936 heavy old pile of wood and lead without hatches and without a self bailing cockpit can sail about in 5' to 7' waves in 35k of wind with gusts above 40k, I'd be a bit worried.

    Say again how you think a cat like this is somehow safer? more seaworth? better?

    I do think cats are fine for hauling tourists around in fine weather, just don't go to sea in one unless you know what you're up against. I certainly don't expect to ever "resolve" this debate. I do know, having sailed for 50 of my 57 years and crossed a number of oceans on both types of boats, when I was going cruising with my family I bought a steel double bottomed (unsinkable) monohull.

    Beau
     
  6. Zed
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    Zed Senior Member

    Just for the record, I have been in what I would describe as "mirco burst" type activity in Broken Bay. It has reasonable hills surrounding and its narrow, the wind can do interesting things in extreme conditions and catch you out. In many ways I would prefer to be at sea or in a much bigger bay.

    Anywhoo I was in a mono that put its rig in the water, as insane as that sounds in a flat water bay... in the same event several monos sank and I heard tell of as large as 38' footers putting spreaders in the water in the same 10-20 minute period... one mono (ultra-light) even went for a kaber (sp)? toss down the bay.

    So while turning a Raider over is probably not hard, they have more in common with a beach cat in terms of ratios than an ocean crosser, I'd not be surprised if the conditions where a little more 'radical' than those reading might expect.
     
  7. BeauVrolyk
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    BeauVrolyk Sailor

    Un-Sinkable Boats

    I have been reading through this thread and just wanted to give an example of a pretty simple and reasonably inexpensive "un-sinkable" (at least REALLY hard to sink) boat design.

    I used to own a Tom Wylie ketch called Saga, of 65' LOL and 18' Beam. She was built in steel with a 6' draft keel that housed a 14' centerboard that would let her sail well when deployed. The board was not ballast. Her construction was welded steel plate with frames ever two feet.

    The interesting, but not novel, design feature was the use of compartments. First, there were two watertight bulkheads, one was 14 feet from the bow and the other was 15 feet from the stern. There were no openings in these bulkheads except through the deck, so one couldn't "leave the door open", as you can in so many supposedly un-sinkable boats. The stern compartment included the rudder shaft and prop shaft exit, so if the stuffing glands leaked it would only flood the aft compartment. A second stuffing glad was mounted where the prop shaft went from the aft compartment to the engine room.

    Second, from a level about one foot above the water line downward she was entirely double bottomed. What that means is the outer skin of steel, that kept the sea out, was copied on the inside by another layer of steel. The space between the two skins, which was substantial, was used as tankage. The only place where the hull was single skinned was right around the engine just at the garboard beside the keel where it would be extremely hard for anything to strike the hull.

    The benefit was that

    1) you could crash into things with either the bow or stern without sinking the boat. The design would float easily with both the bow and stern compartments flooded. The design would also float with the center section of the boat flooded and both ends dry.

    2) If you did hit something, and it did make its way through the 1/4" steel plates, you would simply flood one of the tanks, not put a hole into the hull. The tank would be filled with one of water, diesel, engine oil, vodka (don't laugh there was a built-in vodka tank, or air if it were empty. So, by putting a hole in her you might loose the vodka or a bit of fuel, but you wouldn't sink. These tanks were divided up into 10 separate tanks so if you put a hole in one, you'd have some others full of unpolluted fuel or water to use.

    3) There were about two times as many tanks as we needed, so we would shift the water and fuel to the windward side, giving us about a 4 degree list at the dock, which helped on long beats.

    I do think that you can get a long long way towards building a boat that is darned hard to sink.

    Beau
     
  8. Landlubber
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    Landlubber Senior Member

    You can do anything in this world, it is only a money problem.....
     
  9. BeauVrolyk
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    BeauVrolyk Sailor

    Damn right - that plus time.

    B
     
  10. bad dog
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    bad dog bad dog

    BeauVrolyk said:
    "I was quite surprised by the tone of this post. There are a number of odd assumptions represented here."

    G'day Beau,

    I hope not to surprise you with the tone of THIS post...! I assume you meant the content rather than the tone, which I always intend to be respectful and rational.

    The capsize of Indian Chief:
    Your lovely old cruising boat was obviously capable in all conditions, and would be hard to compare to a steroid-cat like a Raider in any value-laden way. By that I mean, they were designed for different people to do different things in different ways. To compare them in an attempt to determine which one is "better" would be like when that looney who presents BBC's Top Gear (Jeremy Clarkson) running a Toyota Prius around a race track against a BMW M5, saying the Prius isn't as good as the Beemer. Of course the Prius wasn't designed to race, and the Beemer shouldn't be driven in city traffic, where the Prius shines.

    The near-capsize of that fool (said respectfully) in Moreton Bay:
    Those photos were taken on the same day as "my" Dragonfly 920 was being delivered from the Sanctuary Cove Boat Show to its new home at Manly, a bit further up the Qld coast. The new owner wanted to take the outside route (a la the photos), but my old skipper refused, saying "Mate, it's your boat, you can do what you like with it, but if you go outside I won't be on it." There's a video on Youtube somewhere (just can't find it now) of a mono being rolled near there, shot from a helicopter - loses the rig, but somehow the skipper stays in the cockpit. Another shows a Police SharkCat sent to rescue it losing power in the port outboard, losing steerage, broadsiding before a wave and rolling - this was all from about 15 or 20 years ago I think.

    Conclusion:
    There is no conclusion. Not till human history is ended!
     
  11. mydauphin
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    mydauphin Senior Member

    BeauVrolyk's Unsinkable post is 100% Correct and any boat that is more than a day boat should have multiple compartments, double hull or tanks in bottom. Also add hole stuffing survival stuff on board and handy. Otherwise it is just a matter of when. Add that to multiple bilge pumps, multiple batteries, engine driven pump. Etc.... CG should be low. I see some boats with so much stuff on the bridge you wonder how boats doesn't flip over.

    Then in propulsion department, spares for everything including rudders, starters, everything you might to get home in case of a failure.
     
  12. BeauVrolyk
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    BeauVrolyk Sailor

    Bad Dog,

    No offense take on tone or any other matter - happy to discuss this all.

    On the Cat vs my old boat: (which is actually a "racing" boat from 1936, no one would cruise in an IOD) I agree completely - there are different boats built for different folks and purposes. What I was responding to was the age old, and endless, debate about multihulls vs monohulls. I raced multihulls for years, and dearly love them for that. But, I'd never say they were "sea worth" in the classic sense of the term.

    I have a distinct memory of friends of mine trying to reef the cat Stars and Stripes, the one that raced against Fay for that stupid version of the America's Cup, when on an Ensenada Race. They couldn't bring the boat up into the wind or tack because her sterns were so short she'd flip over backwards in 30+ knots of breeze. They couldn't reef going down wind as there was too much strain and friction. So, they hung on and prayed for the wind to drop - it did. I that cat a fun boat - hell yes!! Is it "sea worth", no I don't think so.

    On rolling boats: I remain simply amazed at the conditions that people will sail their boats into, without appearing to have any sense. Here in San Francisco a (now famous) idiot in a small 23 foot boat with the hatches open and two crew not tied on attempted to sail between the south tower of the Golden Gate Bridge and the shore. They chose to do this, which is NOT a passage, while there were surfers riding the break there. I have no idea what they were thinking. Needless to say, they got pitched end over end and the boat did sink, the Ranger 23 is not a boat that likes being upside down. The surfers pulled the sailors from the drink and a diver tossed a line on the boat and allowed some guys to lift her up. No one killed, but what a mess.

    I agree: for each purpose there are better and worse boats. The trick is to insure you really understand the purpose and choose the right boat for it.
     
  13. rayaldridge
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    rayaldridge Senior Member

    For every multi with design flaws there are a thousand monos with design flaws as serious, and this is even less acceptable, because Westerners have been building monos long enough that there is even less excuse for such flaws.

    I think that boats (like steel boats) whose materials outweigh water and which rely on sealed buoyancy compartments, cannot claim to be quite as unsinkable as a boat whose materials weigh less than water. The Titanic was unsinkable in the same sense that Beau's boat was unsinkable. That said, I wouldn't take anything but a steel boat to Antarctica. A capsize there in a multi would not be survivable, in all likelihood.

    But for most sailing, I think a multi is safer and more comfortable than a mono.

    Case in point:

    http://www.telegraph.co.uk/news/wor...couples-yacht-sunk-by-whale-in-Caribbean.html
     
  14. BeauVrolyk
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    BeauVrolyk Sailor

    Well, I must admit I'm a little confused by all this....

    First, in actual fact people have been building and sailing multihulls much longer than monohulls. The folks in Polynesia have sailed multihulls for thousands of years and have a much longer history than the Europeans with their medieval tubs. Further, I really doubt that anyone on this forum, or perhaps anywhere, has any real idea how many boats have design flaws or what those are. To say that there are thousands more in monohulls seems to be just hot air. No facts, statistics, I think it's really just your opinion, which I happen to actually disagree with. Do our two unsupported opinions simply cancel each other - or should we try to be more specific? Or, was your comment really just metaphorical and not meant to be literally true?

    Second, while I completely agree with you, about Antarctica and steel hulls, I certainly don't agree with your comment about multihulls being safer. Your belief that a flooded or swamped multi might float because it is somehow built of something lighter than water is odd. Most multi hull boats are fiberglass and unless they are heavily cored that material actually doesn't float. In addition, most people put an engine, generator, batteries (made of lead), stove, outboard motor for the dingy, aluminum mast and boom, and a whole lot of heavy stuff into a multihull. I really think you should run a small spreadsheet adding up the weight of all that stuff, along with all the personal effects that people bring along (like a tool chest, spare parts, etc...). Then, take an estimate of the boyancy of the hull of whatever material you'd like to choose (wood, glass with foam core, whatever) and see if you really think it would float. I think you'd be quite surprised by the answer - but most folks don't actually do the work to weigh all their junk. We did aboard Saga and we brought over one and half tons of stuff. Do you really think the flotation provided by whatever the hull is made of would float a ton and a half - I doubt it.

    Finally, with respect to comfort, I think this is really a difficult thing to make absolute statements about. I personally don't like the motion of a multi in a sea, like the Pacific off of California. This is because the lee bow of one hull will be stuffed into one wave while the weather stern is in the previous one. Then as the wave passes under the boat there's a lurch as the crest of the wave passed between the hulls. I don't like the lurch. The monohull rolls much more, but the movement is smooth and steady. I do think that a multi standing upright in a calm place like San Diego is wonderful, but few of us sail where there are so few waves and so little wind. Having delivered multi's and mono's up and down the coast of california, I'll take a deep keel heavy mono any time for an easy ride. BTW: the ultra light monohulls are every bit as jerky and uncomfortable as the multihulls.

    B
     

  15. rayaldridge
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    rayaldridge Senior Member

    A) That's probably why I said, "...because Westerners have been building monos long enough that there is even less excuse for such flaws."

    B) Since for every cruising multihull that has existed, more than a thousand cruising monohulls has existed, I think it's a pretty good bet that statistically, I am correct. Of course, I'm referring to the Western world, once again.



    I thought you said said you were familiar with multihulls-- you claim to have raced them a lot. How could you not know that few if any commercially produced multis are now single-skinned glass? (Though some were built in the early years of the multihull movement.) No performance cruising multihulls or racers are produced in single-skin glass-- all are cored, because single-skin glass has a very unfavorable weight-to-stiffness ratio. Only light multis are fast. But even cored monohulls will sink, due to that massive lump of lead they have to keep afloat. Multis don't have that andicap, so they can be unsinkable with a lot less flotation.

    As to gear weight-- this is one area in which the monohull cruiser is superior to the multihull cruiser. You can dump a lot more stuff into the former without making it unsafe-- though you will make it slow(er). In fact, this is a problem with a lot of condomaran cats. By the time they're loaded up with all the goodies, they are no longer unsinkable. There's no way to make a boat foolproof. If you don't understand the limitations of your boat, you probably shouldn't go to sea.

    You must have very odd waves on your ocean. On mine, by the time they get big enough to do more than joggle the boat slightly, their period has grown much longer than any cat I'm ever likely to sail.

    I mean no disrespect, but I really can't understand how anyone who claims to have been offshore in both multis and monos can say they prefer the motion of a mono, though I know lots of folks who do say that. I can only conclude that they love monos so much that their perceptions have lined up with their beliefs. For one thing, the "smooth steady roll" of a mono is far more likely to make the crew seasick than the quicker but lesser amplitude motion of a multi. I've taken folks out in monos and they fed the fishes for days. Same folks in a cat don't get sick at all. What does that tell you?

    Many of the safety advantages of multihulls stem from their stability. A boat that takes better care of its crew is less likely to come to grief due to crew fatigue and bad decisions. The greatest risk offshore, in terms of total fatalities, is man overboard. Multis are far safer than monos in this regard, because of their wide flat stable decks, with mast well inboard.

    Their initial stability is so much greater than any ballasted monohull of similar size that it takes vastly more energy to capsize them, and a monohull that capsizes in violent conditions may come up without its rig and/or hatches. Waves that can capsize a monohull are far more common than waves that can capsize a multi of equivalent size. Even if a monohull comes up in one piece, crew injuries may be severe. In addition, a monohull that finds itself in a bad position relative to a breaking wave can trip over its keel, giving enough leverage to roll the boat over. A multihull with boards up has much less underwater structure over which the boat can rotate.

    One disaster even more common than sinking is dismasting. Because of their light weight and wide staying platform, multis are much easier to jury rig than monos, and their easily-driven hulls are far more efficient under jury rig.

    I could go on, but I hope now that you'll do me the courtesy of grasping that I've thought seriously about these matters.
     
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