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03-05-2018, 07:03
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#16
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Registered User
Join Date: Feb 2013
Location: Bumping around the Caribbean
Boat: Valiant 40
Posts: 4,625
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Dave_S
Assuming safety is in range.
If you did fall into water that cold, are you better to swim fast and create warmth and be in the water for less time or swim at a steady pace and create less heat.
The answer seems straight forward but I wonder if you create more heat and, because of the greater temperature variation your body has relative to the water, you will loose heat more rapidly and may be worse off by swimming faster ?
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Cold water will sap heat from moving arms and legs dramatically faster than if you are stationary and working to minimize skin exposure. The recommended strategy is to curl yourself up as much as possible. Of course, this only makes sense if you're expecting help, such as after setting of a PLB.
If I fell in a mile from shore, at night, with no PLB, I would start swimming for shore no matter what. It's pretty much your only hope and it's slim at best.
A reasonably fit and strong swimmer can swim a mile in 45 minutes, give or take, and that's without clothes or PFD, in a pool in benign conditions. The survival time before hypothermia/unconsciousness in 45 degree water is probably 30 to 60 minutes, based on conditions, personal physiology, etc. so reaching shore is likely in the category of "possible but generally not probable".
I'm extremely careful when solo and I leave the cockpit even in entirely calm conditions. A few years ago I had left a harbor on a beautiful calm evening and went forward to stow fenders and bow lines. The boat hit an uncharted hump, under power, and I very nearly went right over the lifelines. Fortunately I did not, and the boat was aground, so I could have climbed back on had I gone over the side. It could have easily gone the other way. Water temperature was below 40 and I did not have a PFD on. In retrospect I should have shifted the boat into neutral before going forward, and that is now my procedure if I leave the cockpit in similar circumstances.
I should have known better because few years before that I was on a center console in winter at dawn crossing the Chesapeake, on plane doing about 20 knots. The boat hit what I believe was a tree, lifted up on it and slid sideways, diagonally before sliding off. Almost threw me out of the boat. I had the kill switch tether on and a PFD.
Just recounting both experiences to illustrate that the unexpected can happen in essentially benign conditions.
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03-05-2018, 07:12
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#17
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Registered User
Join Date: Aug 2011
Location: Lower Chesapeake Bay Area
Boat: Bristol 27
Posts: 10,533
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by a64pilot
Or maybe try to ball up and not move?
I’d assume creating heat will have you in hypothermia faster as you lose what energy you had?
Moving through the water continues to move cold water over you removing heat? Maybe reducing surface area and just floating, may make you last longer?
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Ball up and not move?? Last longer floating in 40 plus degree water?
Why? What are you waiting for?
He mentioned the river is only 2 miles wide so you would have to go for it.
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03-05-2018, 07:20
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#18
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Registered User
Join Date: Aug 2011
Location: Lower Chesapeake Bay Area
Boat: Bristol 27
Posts: 10,533
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
" Just recounting experiences to illustrate that the unexpected can happen in essentially benign conditions"
Just before I left to join the military I decided it would be fun to stand on the bow of my 16' scow almost on plane
It was really fun. It was flat calm. I was 19 years old and alone. Not wearing a PFD. It was in March on the Southern Chesapeake Bay, East side, mouth of Pungoteague Creek. I was maybe 1-2 miles from land. Water temp was probably in the 40's
I happened to glance back and noticed that the outboard was starting to turn so I jumped/dove for the center of the boat as the outboard slammed all the way to a max turn almost flipping the boat and sending it turning in circles
I have often thought about this day over the years
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03-05-2018, 07:29
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#19
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Registered User
Join Date: Aug 2010
Posts: 3,105
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Dave_S
Assuming safety is in range.
If you did fall into water that cold, are you better to swim fast and create warmth and be in the water for less time or swim at a steady pace and create less heat.
The answer seems straight forward but I wonder if you create more heat and, because of the greater temperature variation your body has relative to the water, you will loose heat more rapidly and may be worse off by swimming faster ?
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This is an interesting topic. I was listening to an MOB situation over VHF last summer. The incident occurred in a heavy traffic area and I was at least 2-3 hours away, so there was no point in me attempting to respond.
A man fell overboard in an area with a strong current. His wife didn't know how to operate the boat but was familiar with VHF protocol. She called a mayday. He drifted very quickly from the boat. He attempted to swim for an island about 1 mile away.
He drowned within 15 minutes in water temps around mid 60's F.
It's not just the hypothermia, it's exhaustion.
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03-05-2018, 07:41
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#20
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Moderator Emeritus
Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 31,351
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by thomm225
Ball up and not move?? Last longer floating in 40 plus degree water?
Why? What are you waiting for?
He mentioned the river is only 2 miles wide so you would have to go for it.
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It was a general question based on what increases your survival time.
I don’t believe it had anything to do with this incident.
There is also the gasp reflex when hitting cold water, for some it’s over then.
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03-05-2018, 08:00
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#21
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Registered User
Join Date: Aug 2011
Location: Lower Chesapeake Bay Area
Boat: Bristol 27
Posts: 10,533
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Shrew
This is an interesting topic. I was listening to an MOB situation over VHF last summer. The incident occurred in a heavy traffic area and I was at least 2-3 hours away, so there was no point in me attempting to respond.
A man fell overboard in an area with a strong current. His wife didn't know how to operate the boat but was familiar with VHF protocol. She called a mayday. He drifted very quickly from the boat. He attempted to swim for an island about 1 mile away.
He drowned within 15 minutes in water temps around mid 60's F.
It's not just the hypothermia, it's exhaustion.
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Lots of folks of a certain age tend to stop working out and just think they can do with their bodies what they used to do.
If you are near or over 60, you may want to see how long you can actually swim, or run
You may be surprised at how hard it is if you don't workout regularly
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03-05-2018, 08:20
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#22
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Registered User
Join Date: Mar 2016
Posts: 118
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
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03-05-2018, 08:36
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#23
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Moderator
Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,865
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by LakeSuperior
. . . My sense is the heat transfer to the cold water by far overwhelms the bodies ability to make heat so the difference in internal heating from moderate to extreme exertion is negligible. Some benefit is reported for reducing convection by remaining motionless and keeping the warming water trapped near the skin. Time is of the essence when immersed in cold water.
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Your sense is correct.
Without a drysuit, survival time is measured in minutes in 40F (5C) water.
According to this:
Cold Water Survival
Debilitation occurs in 15 to 30 minutes in 5C water.
There is no way that physical activity can generate enough heat to keep up with the massive heat transfer via immersion.
I now have a drysuit for sailing in rough weather and cold water. I think that MOB into 5C water is basically unsurvivable without a drysuit.
__________________
"You sea! I resign myself to you also . . . . I guess what you mean,
I behold from the beach your crooked inviting fingers,
I believe you refuse to go back without feeling of me;
We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
Walt Whitman
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03-05-2018, 09:04
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#24
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Senior Cruiser
Join Date: Oct 2014
Location: Cruising the northern Bahamas until June
Boat: Leopard 40 2009
Posts: 600
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
The absolute best article I've seen on hypothermia is by Mario Vittone, a former USCG rescue swimmer. He separates some of the myths and truths, also expressed in this thread:
https://www.soundingsonline.com/voices/hypothermia
I highly recommend Mario's other postings as they are fact-based and obviously come from a lifetime of pulling people out of very bad situations: https://www.soundingsonline.com/voic...-rescue-at-sea
__________________
John Trusty
Better to trust the man who is frequently in error than the one who is never in doubt." -- Eric Sevareid
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03-05-2018, 09:46
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#25
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Moderator
Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,865
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by thomm225
Ball up and not move?? Last longer floating in 40 plus degree water?
Why? What are you waiting for?
He mentioned the river is only 2 miles wide so you would have to go for it.
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How long does it take you swim a mile in your clothes? Or even half a mile?
A very athletic swimmer in a warm swimming pool can do a mile in about half an hour. I doubt many of us could do it in less than hour even without clothes on. I reckon half a mile in clothes in 5C water is basically impossible, but I think I would probably try it anyway, just so that I would die trying, rather than floating around waiting for an extremely unlikely rescue.
__________________
"You sea! I resign myself to you also . . . . I guess what you mean,
I behold from the beach your crooked inviting fingers,
I believe you refuse to go back without feeling of me;
We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
Walt Whitman
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03-05-2018, 09:50
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#26
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Registered User
Join Date: Aug 2011
Location: Lower Chesapeake Bay Area
Boat: Bristol 27
Posts: 10,533
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Dockhead
How long does it take you swim a mile in your clothes? Or even half a mile?
A very athletic swimmer in a warm swimming pool can do a mile in about half an hour. I doubt many of us could do it in less than hour even without clothes on. I reckon half a mile in clothes in 5C water is basically impossible, but I think I would probably try it anyway, just so that I would die trying, rather than floating around waiting for an extremely unlikely rescue.
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That was my point.
I'd give it a shot and see if I could make it ..........if I couldn't get back to the boat.
If help did arrive, I'm sure they would check on any swimmer
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03-05-2018, 10:06
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#27
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Moderator
Join Date: Jan 2010
Location: Minnesota
Boat: Tartan 3800
Posts: 4,848
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Dockhead
Without a drysuit, survival time is measured in minutes in 40F (5C) water.
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Other forms of immersion protection work, too, notably wetsuits.
I have been scuba diving in 40F/5C water, at depth, with a 7mm wetsuit, for dives an hour long. Since wetsuits compress with depth, a thinner suit would provide the same performance at the surface. Wetsuits also provide floatation, and are inexpensive enough to be affordable.
I wear a 3/2mm (body/arms+legs) wetsuit on some river trips over cold water. It is probably not enough to allow me to stay in 40F/5C water indefinitely but is enough for me to get to safety. I believe I could swim a mile in a 3/2 suit and wetboots with no other gear, in cold water.
The drawback is that people don't have them unless they are divers or are serious about cold water skiing or windsurfing or something. They have to fit to be effective.
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03-05-2018, 10:23
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#28
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Registered User
Join Date: Jan 2008
Boat: Teak Yawl, 37'
Posts: 2,985
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Quote:
Originally Posted by Jammer
Other forms of immersion protection work, too, notably wetsuits.
I have been scuba diving in 40F/5C water, at depth, with a 7mm wetsuit, for dives an hour long. Since wetsuits compress with depth, a thinner suit would provide the same performance at the surface. Wetsuits also provide floatation, and are inexpensive enough to be affordable.
I wear a 3/2mm (body/arms+legs) wetsuit on some river trips over cold water. It is probably not enough to allow me to stay in 40F/5C water indefinitely but is enough for me to get to safety. I believe I could swim a mile in a 3/2 suit and wetboots with no other gear, in cold water.
The drawback is that people don't have them unless they are divers or are serious about cold water skiing or windsurfing or something. They have to fit to be effective.
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I don't think you could do it in 40 deg water without fins. Your head/neck in the water would freeze you out in the 1 to 1.5 hours it would take you to swim the mile. This assumes you are not a current lap swimmer. Additionally, the 3/2 wet suit would work to further tire your arms and legs. A 3/2 wetsuit with the increased convection (cooling) due to water circulation from swimming motions would do you in before a mile. It is just not enough insulation. BTW, I own a 1/3 wetsuit, a 7 mil wet suit, and a Viking dry suit.
Have spent a lot of dive time in the ice through the years with the 7 mil and Viking. I have experienced dives in ice pressure ridges in Lake Superior that go over 100 feet deep.
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15-05-2018, 10:30
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#29
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Registered User
Join Date: Mar 2016
Posts: 118
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
Any news here ? Have him been found ?
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15-05-2018, 10:52
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#30
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Senior Cruiser
Join Date: Jan 2010
Location: PORTUGAL
Posts: 30,616
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Re: Yachtsman missing after unattended boat washes up on shore -- Mississippi
If I may suggest.. a large plastic bin liner tucked somewhere in the LJ.. if you go over pull it out and get inside.. Curl up and close it tight round your neck.. should cut down on the speed of heat loss.
Then all you have to worry about is your head, neck and ears..
__________________
You can't beat a people up (for 75yrs+) and have them say..
"I Love You.. ". Murray Roman.
Yet the 'useful idiots' still dance to the beat of the drums.
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