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-   -   Survival in North Sea around 5 mins? (https://www.pprune.org/private-flying/531274-survival-north-sea-around-5-mins.html)

PompeyPaul 5th Jan 2014 17:17

Survival in North Sea around 5 mins?
 
I was always led to believe a ditch into the north sea would be rapidly fatal. Was reading this article about a lady who fell off of a ferry and survived in the water, at night, for 30 mins.

BBC News - Ferry fall survivor Jeni Anderson reunited with crew

Genghis the Engineer 5th Jan 2014 17:23

In September.

G

wiggy 5th Jan 2014 17:58

Wot Genghis said...

AFAIR it "we" (military Fast Jet) used to have to wear immersion suits once the sea temp was at or below 10 celsius...which from memory used to happen around September for the North Sea.

With the very important caveat that every case is different I'll offer you these tables:

Survival Time in Cold Water

Genghis the Engineer 5th Jan 2014 18:50

Sea surface temperatures

Shows in September temperatures around 14 - 17 deg.C this last year. I'm not aware of anything that causes it to change much year on year.

http://www.bsh.de/aktdat/mk/nordsee/ns201337.gif

Relatively speaking, quite warm and comfortable. Wiggy's table would give you a couple of hours before exhaustion set in in a reasonably fit adult.

G

englishal 5th Jan 2014 19:00

They always quote "worst case" times in survival time in cold water.

If you are a little bit tubby, fit, moving a lot, etc., then you will probably survive longer. Some people go swimming in the arctic and survive for seemingly amazing times, so it is possible.

Genghis the Engineer 5th Jan 2014 19:09

True, also women generally can survive longer - thanks to the layer of insulating subcutaneous fat that under all other circumstances, they're likely to complain about.

I suspect that in most cases the real survival time is dictated by the ability to keep one's head above water - particularly given that few people are really that strong or well trained as swimmers.

G

Maoraigh1 5th Jan 2014 19:16

If wearing a lifejacket, and woolen clothing under waterproofs, a layer of water will be trapped, and warm-up. Movement would lose that.
The water will not be at its coldest for a few months yet, if I recall the North Sea Pilot (Admiralty publication)
Survival time, clothed, varies greatly.
Thirty + years ago, after a trawler went down off Iceland in winter, the mate was the sole survivor . After hours in the water, he swam ashore, climbed a cliff, and managed to reach an inhabited house.

piperboy84 5th Jan 2014 19:24

My dad is 80, up until 7 years ago the crazy old bastard used to drive down to the beach at Carnoustie and swim in the North Sea in all but the coldest of days. One day he ran into the water and the shock of the cold made him violently flinch which caused his falsers to be launched into the surf never to be seen again, he was not a happy camper.

abgd 6th Jan 2014 00:32

My great uncle was involved in some trials where they tied a rope to him and threw him out of a lifeboat off the Edinburgh coast and timed how long it took before he went under. I'm not sure what time of year it was.

If people tried swimming, they tended to get cramps and sink pretty quickly. If they stayed still and conditions were calm then some of them did last much longer. I can't remember how long, but I think it was in the region of hours for some people. Genghis is right in that people sank before they became life-threateningly hypothermic.

Google scholar has lots of links to theoretical studies, and I imagine something similar must have been written up though I can't immediately find it. I suspect my uncle's experiment wouldn't make it past the ethics committees these days.

Flyingmac 6th Jan 2014 07:51

For much of the year North Sea temperatures exceed those on land. Particularly in late Autumn- Winter.

The problem is that water will leech heat from the body around 20X faster than air will. Hence the advisability of a drysuit.

cockney steve 6th Jan 2014 17:32


in some trials where they tied a rope to him and threw him out of a lifeboat
Typical tight-fisted Jocks....go shark-fishing and too tight to buy bait:}

riverrock83 7th Jan 2014 01:55

When working for a large ferry company on the Irish sea, we were taught to remain still, tucked into as tight a ball as possible with knees as close to chest as life jacket would allow and to group together in concentric circles in the water, with the most vulnerable in the middle (I would have been responsible for potentially hundreds of passengers, although if groups were in the water it really would have been a bad day!).

I can't remember the figures quoted, but my memory was around 1 hour which could be extended to many hours if people grouped together (etc) and didn't panic.

No idea what these figures are based on, but they tally with what I was told:
Survival Time in Cold Water

Heston 7th Jan 2014 09:02

The data for survival time in cold water is based on Nazi experiments on concentration camp inmates. Where else could such data come from?


Nazi human experimentation - Wikipedia, the free encyclopedia

Genghis the Engineer 7th Jan 2014 09:19

Nowadays we'd hopefully use computer modelling.

I have a copy of a British commando training manual from the start of WW2. There's a table there showing how long people will take to die from various types of attack. It isn't stated how that was worked out, but one suspects not entirely through anecdotal evidence either.

G

hoodie 7th Jan 2014 09:26

The trouble with computer modelling, regardless of the field of study, is that the model requires validation with real world data. :(

Sillert,V.I. 7th Jan 2014 10:22

Had to do some maintenance in my swimming pool recently; the water temp is about 7C and I simply couldn't believe how quickly my body went numb on entering the water.

Did it in the end by standing in a hot shower wearing a tracksuit, putting lightweight waterproofs on over that & then getting in the pool.

I can easily believe you wouldn't be able to function in any meaningful way once immersed in the North Sea.

I always carry a liferaft when crossing the channel in a single but tbh I'm not optimistic about my chances of successful deployment and entry should the worst happen.

riverrock83 7th Jan 2014 10:31

There are a number of courses run throughout the country on deployment and entering life rafts (and righting them if they turn over!).
I completed a course before working for a shipping company, but the practicalities are the same.
The rafts we were using were larger (10 person AFAI remember) and we all managed to get in, although it was a real struggle for some people.

Training was in a swimming pool but final scenario was in darkness with wave machine, flashing "lightning" and noise of thunder which really concentrated the mind!

dubbleyew eight 7th Jan 2014 10:43

I go swimming in the ocean here in perth wearing togs and a tee shirt.
it has truly amazed me just how warm the tee shirt keeps me in the water.

Sillert,V.I. 7th Jan 2014 10:51


Originally Posted by riverrock83 (Post 8251159)
Training was in a swimming pool

The difference between a swimming pool at normal swimming pool temperatures and one at 7C has to be experienced to be believed.

It took me by surprise.

NorthernChappie 7th Jan 2014 12:00


My dad is 80, up until 7 years ago the crazy old bastard used to drive down to the beach at Carnoustie and swim in the North Sea in all but the coldest of days. One day he ran into the water and the shock of the cold made him violently flinch which caused his falsers to be launched into the surf never to be seen again, he was not a happy camper.
Its a Carnoustie thing. My version of yours took up cycling after he was officially classed as blind. Gave it up after a crash and hospital stay. Remaining mother is now doing it by driving - dementia, dicky hip, walking stick et al.

Anyway on topic, only way I get in the North Sea is dry suit diving gear.


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