My new perspective on multi safety, opinions?

Discussion in 'Multihulls' started by peterchech, Oct 16, 2012.

  1. oldsailor7
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    oldsailor7 Senior Member

    Bruce.
    A six HP outboard in reverse is no match for a big mainsail with the boom hard up against the shrouds in a good gust. :eek:
     
  2. bruceb
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    bruceb Senior Member

    thinking small

    These boats would work a lot better with a 25- and be safer if we left those wind catching masts and sails off completely:rolleyes: B (I have a 5, it won't go to weather in reverse either)
     
  3. masalai
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    masalai masalai

    To my way of thinking, there is another risk and greater risk of mishap... - It needs another pair of eyes to ensure avoidance, as I feel the greatest risk is being hit by a MUCH larger "commercial" vessel where the bridge is otherwise occupied making a coffee or illicitly chatting with a partner on the radio in the absence of the "responsible officer" who is also mistakenly reliant on 'electronic devices', - - - A slight bump may or may NOT be felt on the large vessel? and another cruising or racing yacht "disappears mysteriously"...
     
  4. Stumble
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    Stumble Senior Member

    These are actually pretty common on the big solo racers. There are a umber of different systems, some of which are tied to load cells with predetermined load release points, others that use heel, or speed, or any other variable the skipper sets.

    Take a look at http://www.oceandatasystem.com/?mode=developpement-ods-peripheriques for some examples.
     
  5. michael pierzga
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    michael pierzga Senior Member

    Inabilty to dump power is a classic multi hull problem. A rather nice 40 cruising cat just arrived at the shipyard without its mast. The skipper told me that on a fair sailing day under auto pilot, they got under a cloud...the wind went from 10 knots to 25 , apparent wind built rapidly and that they just couldnt respond fast enough. Mast over the side. The skipper is an experience sailor.
     
  6. peterchech
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    peterchech Senior Member

    That's kind of what I mean

    My keelboat rounds up when overpowered. Sure it might auto tack and get knocked down in worst case scenario, but those sails are depowered within seconds by the round up and the heel response. Worst case scenario s a crash jibe dw, which at worst might rip a sail or sheer a gooseneck.

    I'm concerned with a boat like a Gemini, which has relatively little bridge deck clearance. If overpowered, it won't round up, and might get the entire bridge deck underwater if it runs into the next wav, possibly pitch poling but certainly stressing the rig to its limits. Smallish Trimarans and higher performance cats would prob pitch pole in these circumstances.

    I have read a few accounts online indicating that some small tris, such as the buc, will actually round up when overpressed. I don't see how that's possible, since the drag from the lee AMA would be significant, but has anyone here experienced this? Will, say, a corsair 24 have this tendency to round up?
     
  7. michael pierzga
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    michael pierzga Senior Member

    Im not a multi guy, so I dont know their behavior. I do know that multis accelerate and build apperant wind very fast. The is different from mono hulls who simply put the rail down and rumble until the helmsman gets her back on her feet
     
  8. cavalier mk2
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    cavalier mk2 Senior Member

    Tis true, multihulls dispel the extra energy by acceleration. A speed limited hull form is actually a liability here. In the case of the 40 ft cruising cat it sounds like he needed stronger rigging. Designing a boat to lose its rig instead of capsize is pretty drastic. Multihulls used to be designed with a smaller rig for their size than monos, due to the lack of ballast they didn't need it for decent performance. For cruising it is still a good idea, over large rigs need to be handled with a increase of caution. The oldest safety approach for all boats is to have a sharp knife by the sheets in case of a jam. For Peterchech I would encourage you to get more experience with multihulls, a good one will reassure you within a season.
     
  9. bruceb
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    bruceb Senior Member

    round ups

    Peter, there is a u-tube video of Buc 24 Capricorn "The green death trap";) going fast under chute, sticking the bows way in, and then recovering. I have only stuck a bow once, and my boat also seemed to recover on its own. Of course, a cleated or jammed spinnaker could or would pull it over- there is always a limit. With normal working sails up, even with my tall main, it seems recoverable in anything under 30kts. Above that or in waves, seamanship had better take over. My boat (with bare pole) has stayed in a mooring field in thunderstorm gusts over 50kts, and seemed to be the least affected of any of the boats of all sizes around it. B
     
  10. Freenacin
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    Freenacin Junior Member

  11. Freenacin
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    Freenacin Junior Member

    That would depend on your point of sail.
     
  12. peterchech
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    peterchech Senior Member

    Queens day storm was regarding large cats in survival conditions, I am more concerned with under 30' multis trying to go fast in heavy winds.

    And even if it floats, an upside down f-24 for example, leaves little protection from the elements. At least up here in New York, that water is coooooold...

    As for jammed spinnaker sheets, ihad just this happen on a c&c 32 a few days before hurricane sandy blew through here. Spaghetti got knotted at the turning block, and the loads were too great to un knot it. I was able to blow the halyard and go shrimping, but it could have been bad...
     
  13. michael pierzga
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    michael pierzga Senior Member

    One technique we use on big boats when flying spinnakers is a breaker shackle at the tack. A breaker is a standard sparcraft with a lanyard rove thru its trigger. When out of control or in a man overboard dump , you pull on the trigger lanyard from the cockpit and poof...the sail is depowered.

    The red line is tack downhaul
     

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  14. bruceb
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    bruceb Senior Member

    perspective

    Please guys, don't you think it is about time we put this thread to bed?
    Michael, I think anything that helps prevent a capsize is a good addition, and I think a trip shackle is a good idea, but on small tris like mine, I (along with the crew) am often 9' away from the cockpit (on the end of a long tiller) in heavy conditions. The tack is also at the end of a seven foot movable bowsprit. Practical engineering of multiple release points becomes an issue, and deciding to release the tack instead of a sheet also becomes an problem- I don't want to end up with a chute streaming from the masthead either. These things happen really fast on a small light boat. I might still add the trip shackle, but more as a back up.
    Peter, I have been through several storms where small keel boats were knocked down (including mine), rolled, and some filled/sunk. In most cases I have witnessed, at least some or all of the crew ended up in the water. A floating multi gives you at least as good a chance of rescue as any other kind of boat, and possibly better as it doesn't tend to drift away as quickly if it is capsized. Equipment/boat damage is another issue- multis are tough to salvage in many cases. However, they are usually afloat and a lot easier to find:rolleyes:
    I am only aware of a few C-24s capsizing (and there are a lot of them) , and no stock B-24s (but most were built along time ago and might not have been recorded). A new C-24 Sprint did capsize in Florida in the last couple of years, but it carries a big rig about like mine and was in a local storm. Yes, they will go over, as will mine. You pay your money, you practice good seamanship, and you take your chances in ANY boat. Or stay at home. B
     

  15. CT 249
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    CT 249 Senior Member

    That is completely wrong. Many highly experienced crews still do a lot of offshore racing, and in fact in many ways the experience level of offshore yachts is HIGHER than it was 25 years ago.

    I collect old S-H programmes and when I look at the experience listed for crews of the '60s to '80s I am surprised at how LITTLE experience in this respect we had, compared to today.

    This can be shown by personal experience (in my first Hobart, 32 years ago, I was the only person on my boat or the boat I was earlier listed to sail who had done a race over 500 miles and we would not qualify under modern rules) or checking factual records such as the Sydney-Hobart programmes. Just go to the website and see how many previous S-H races the typical crew has done these days. Several people I know have done over 25 - when I was a kid only three people alive had done that many.

    Deliveries are not all done by pros - many of my friends do them, for free.

    Please don't sit at a keyboard and slag off other sailors.
     
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