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05-08-2016, 17:47
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#196
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Registered User
Join Date: Aug 2013
Location: Back in the boat in Patagonia
Boat: Westerly Sealord
Posts: 8,378
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by Training Wheels
Catamaran not so good in ice. Can jam up between the hulls.
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Fit wheels, sail on top of ice..... try that on a mono...
I think this thread has gone that far off topic that the OP has long since left the bullding.
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05-08-2016, 18:18
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#197
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Registered User
Join Date: Oct 2007
Location: Geelong,Australia
Boat: Lagoon 440 Pathfinder
Posts: 845
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Re: Catamarans in 50kt winds
When i got hit with 55 knots we only had one reef in the main and full headsail out.
Sounds like we are lucky we did not flip over being on a cat.
Sent from my iPad using Cruisers Sailing Forum
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05-08-2016, 18:23
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#198
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Registered User
Join Date: Sep 2006
Posts: 9,398
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Re: Catamarans in 50kt winds
Lucky, maybe. From CF I've learned that we must be capsizing several hundred times a day. It gets so you really don't even notice it.
__________________
"You CANNOT be serious!"
John McEnroe
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05-08-2016, 18:48
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#199
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Registered User
Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43 and OPBs
Posts: 12,891
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by tomfl
Not sure your understanding of the speed limitation physics is the same as mine. A displacement hull creates a bow wave and the faster the boat goes the bigger the wave. At some point the wave gets so large that the displacement hull is basically going up hill on the wave and this is the max speed.
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It's not the size of the wave that matters. It's the wave length.
To grossly over simplify:
The faster the boat speed, the greater the wavelengthof the bow wave created. As long as the wavelength is less than the LWL, the boat is effectively supported by two waves. Once the boat speed causes the wavelength to exceed the LWL, the bow is on the crest and the stern in the trough of a wave - meaning that it is constantly trying to climb the wave.
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05-08-2016, 19:00
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#200
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Registered User
Join Date: Nov 2011
Posts: 33
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by KJThomas
An inverted cat is very uncommon for cruising cats. And usually the crew survives. The death toll is minimal compared with keel boats. Keel boats sinking without trace happens all the time. Several each year in the South Pacific............
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I don't think you have correct facts there.
I'd be interested if you can name even 3 of these over the past 5 years ? The last I'm aware of was Nina which was a geriatric wooden boat in need of a lot of work to make it safe that only left NZ because it was going to have to pay import tax.
When we talked in detail to a naval architect about our requirements there was no question of what hullform we should use for our own requirements.
It appears that there are a lot of subverted facts attached to opinions.
Opinions are free and often worthless unless shaped by relevant experience or in depth learning.
As for "the crews usually survive", that's unfortunately and tragically incorrect. The opposite is the grim reality of rough weather inversion. As more boats overturn in rough weather the trend seems to be close to the total loss of everyone aboard. Can you give one example of a Cat overturning in a storm where the majority of people aboard survived rather than the opposite? There are plenty of examples of horrific tragedy when you look. Yet you'll find a lot of misleading biased statements to the contrary from various designers and marketers.
That it's a myth that cats are safe platforms when inverted in heavy weather needs to be hammered home into designers and operators skulls. Alarmingly it's nearly always really experienced offshore skippers that get killed.
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05-08-2016, 19:36
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#201
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Registered User
Join Date: Jun 2007
Location: SW Florida
Boat: FP Belize, 43' - Dot Dun
Posts: 3,823
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by Souther Wombat
....
As for "the crews usually survive", that's unfortunately and tragically incorrect. The opposite is the grim reality of rough weather inversion. As more boats overturn in rough weather the trend seems to be close to the total loss of everyone aboard. Can you give one example of a Cat overturning in a storm where the majority of people aboard survived rather than the opposite? There are plenty of examples of horrific tragedy when you look. Yet you'll find a lot of misleading biased statements to the contrary from various designers and marketers.
That it's a myth that cats are safe platforms when inverted in heavy weather needs to be hammered home into designers and operators skulls. Alarmingly it's nearly always really experienced offshore skippers that get killed.
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Change in course proves fatal | Soundings Online
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05-08-2016, 19:55
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#202
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Registered User
Join Date: Nov 2007
Boat: Seawind 1000xl
Posts: 7,430
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by Souther Wombat
I don't think you have correct facts there.
I'd be interested if you can name even 3 of these over the past 5 years ? The last I'm aware of was Nina which was a geriatric wooden boat in need of a lot of work to make it safe that only left NZ because it was going to have to pay import tax.
When we talked in detail to a naval architect about our requirements there was no question of what hullform we should use for our own requirements.
It appears that there are a lot of subverted facts attached to opinions.
Opinions are free and often worthless unless shaped by relevant experience or in depth learning.
As for "the crews usually survive", that's unfortunately and tragically incorrect. The opposite is the grim reality of rough weather inversion. As more boats overturn in rough weather the trend seems to be close to the total loss of everyone aboard. Can you give one example of a Cat overturning in a storm where the majority of people aboard survived rather than the opposite? There are plenty of examples of horrific tragedy when you look. Yet you'll find a lot of misleading biased statements to the contrary from various designers and marketers.
That it's a myth that cats are safe platforms when inverted in heavy weather needs to be hammered home into designers and operators skulls. Alarmingly it's nearly always really experienced offshore skippers that get killed.
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Chris White Atlantic 57, all crew survived.
Chris White 42, all crew survived.
Take some time and do a Google search, there are many more.
Sent from my iPad using Cruisers Sailing Forum
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05-08-2016, 20:01
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#203
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Registered User
Join Date: Jun 2015
Location: New Zealand
Boat: Custom sailing catamaran
Posts: 187
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by Souther Wombat
I don't think you have correct facts there.
I'd be interested if you can name even 3 of these over the past 5 years ? The last I'm aware of was Nina which was a geriatric wooden boat in need of a lot of work to make it safe that only left NZ because it was going to have to pay import tax.
When we talked in detail to a naval architect about our requirements there was no question of what hullform we should use for our own requirements.
It appears that there are a lot of subverted facts attached to opinions.
Opinions are free and often worthless unless shaped by relevant experience or in depth learning.
As for "the crews usually survive", that's unfortunately and tragically incorrect. The opposite is the grim reality of rough weather inversion. As more boats overturn in rough weather the trend seems to be close to the total loss of everyone aboard. Can you give one example of a Cat overturning in a storm where the majority of people aboard survived rather than the opposite? There are plenty of examples of horrific tragedy when you look. Yet you'll find a lot of misleading biased statements to the contrary from various designers and marketers.
That it's a myth that cats are safe platforms when inverted in heavy weather needs to be hammered home into designers and operators skulls. Alarmingly it's nearly always really experienced offshore skippers that get killed.
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Because of my job I receive all the marine accident and incident reports worldwide. I don't see any sign of horrific amounts of fatalities in cruising multihulls. Rather the reverse.
Not the same for racing yachts, multi and mono. But still not high compared with the numbers sailing.
Statistically you are much more likely to die in a car accident. Or while gardening.
I just broke my ankle gardening.
This is fact. Not opinions. Which there appears to be rather too much of in this thread.
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05-08-2016, 20:05
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#204
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Registered User
Join Date: Jun 2015
Location: New Zealand
Boat: Custom sailing catamaran
Posts: 187
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Re: Catamarans in 50kt winds
Pity the Nina was not a geriatric multi.
The crew may have still been afloat.
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05-08-2016, 20:28
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#205
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Registered User
Join Date: Nov 2011
Posts: 33
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by valhalla360
..........
The gust that goes from 5kts to 50kts in a couple of seconds (yeah, freak gust combined with coming out from behind a headland) that could flip a cat will induce a roll moment to the mono, so even though it spills the wind, the mono will still be rotating after the wind starts spilling and could meet the definition of knock down. Even if it doesn't meet the definition of knock down, a quick roll to 60degrees could clear everyone violently out of the cockpit with the boat popping back up and sailing off on it's own. Not really a better outcome unless you own the boat and it was stolen by someone you don't like.
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There's a lot of conjecture like this but no real world observation (examples).
Also cruising ballasted offshore monohulls are designed not to sink (nor lose their masts) from a knockdown if they are ISO compliant as posted before they can't.
And the roll from a gust in anything remotely close to a sensible cruising boat is quite slow and you would have no trouble in terms of staying aboard unless it were a particulalry unseaworthy design.
I've sailed a lot in high lattitudes in all manner of sizes of ballasted monohulls, being hit by sudden squalls of 50 to 80 knots is just a matter of saving your sails, there's no danger whatsoever of inversion the way there is in a cat from sudden severe winds like that.
The heavy cruising cat we knew of that blew over in Greece anchored was inverted by a gust estimated at around 80 knots. Land funnels and concentrates wind.
They had done 54000 miles in that cat prior to the disaster over 15 years and as they said there was no level of seamanship that could have prevented that capsize. None of the monohulls in the anchorage did anything more than drag anchor. Tragically a man drowned after falling in while fending off another boat that had dragged down on them trying to save his gellcoat.
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05-08-2016, 20:38
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#206
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Registered User
Join Date: Nov 2011
Posts: 33
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by KJThomas
Because of my job I receive all the marine accident and incident reports worldwide. I don't see any sign of horrific amounts of fatalities in cruising multihulls. Rather the reverse.
Not the same for racing yachts, multi and mono. But still not high compared with the numbers sailing.
Statistically you are much more likely to die in a car accident. Or while gardening.
I just broke my ankle gardening.
This is fact. Not opinions. Which there appears to be rather too much of in this thread.
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No not high at all, and I have no problem with Cats and I'll probably buy another. But it's about mangaing risk and understanding vulnerabilities and getting a boat that suits the conditions you expect to encounter.
The horrific deaths are low statistically but high for inversion in storm force conditions. Separate out the statistics and look at the facts of heavy weather inversion for cats especially those that are well offshore.
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05-08-2016, 20:39
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#207
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Moderator
Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,467
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by smj
Chris White Atlantic 57, all crew survived.
Chris White 42, all crew survived.
Take some time and do a Google search, there are many more.
Sent from my iPad using Cruisers Sailing Forum
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Dunno about the 42, but when the 57 flipped, it was not sustained heavy wx, rather it was squally moderate wx. It was that situation that lead to the flip, for t hey had survived several squalls previously, and the final one was just a bunch stronger, and hence they were overcanvassed. The sea state was fairly moderate, not like storm conditions at all.
Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
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05-08-2016, 20:45
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#208
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Registered User
Join Date: Nov 2011
Posts: 33
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by smj
Chris White Atlantic 57, all crew survived.
Chris White 42, all crew survived.
Take some time and do a Google search, there are many more.
Sent from my iPad using Cruisers Sailing Forum
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Anna (the 57) was certainly not in a storm, the sea was quite benign and the cat blew over from a combination of a sudden squall line and too much sail area.
What was the 43 I cannot find any reference to that ? as for many more I'd like to see some links as I really doubt it unless they were day sailors very close to rescue and observed by others.
I want offshore boats on a passage alone that are inverted in storm conditions when the sea has inverted the boat. My premise is that it's nearly an untenable platform and incredibly dangerous and leads to the death of a significant number of the people aboard.
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05-08-2016, 21:00
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#209
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Registered User
Join Date: Sep 2006
Posts: 9,398
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Re: Catamarans in 50kt winds
You may find it difficult to get what you want, because in a sustained storm cruising boats will be under bare poles, and capsizes due to wave action alone are very rare.
But if it leads to the deaths of a significant number of people, (say at least 10 per year?) I'm sure you could provide links to all these stories of tragedy?
Apparently the Rose Noelle was rolled by a big wave, but that's a tri. The crew survived though.
__________________
"You CANNOT be serious!"
John McEnroe
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05-08-2016, 21:15
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#210
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Marine Service Provider
Join Date: Dec 2006
Location: Brisbane Australia
Boat: Multihulls - cats and Tris
Posts: 4,873
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Re: Catamarans in 50kt winds
Quote:
Originally Posted by Souther Wombat
My premise is that it's nearly an untenable platform and incredibly dangerous and leads to the death of a significant number of the people aboard.
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Any facts to support that assertion?
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