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Old 08-04-2018, 11:02   #136
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

This is a great thread. I have learned a lot.

I thought this might be a good time to introduce a recent [and brief] article written by a retired USCG rescue swimmer. It isn't about rescue techniques.

I suspect most contributors to this thread can relate to what he has to say. I know I do...

Here is an excerpt from The Wrong Argument: Why Experience Doesn't Matter... as relates to the opening premise of this thread:

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Professionals do not understand the risks better just because they have been exposed to them more — they have just managed to dance around them where novices may not have. Or, as Laurence Gonzales puts it, “The word ‘experienced’ often refers to someone who’s gotten away with doing the wrong thing more frequently than you have.” That’s it. It is exactly that experience — the experience of nothing bad happening — that allows the experienced to nonchalantly decide which rules to follow and which ones don’t apply to them or shouldn’t.
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Old 08-04-2018, 11:57   #137
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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I think lifeline netting is in my future, however much I hate how it interferes with mooring lines and other things.
Last summer we took the netting off after 5 years, used mainly to keep the pug on board the boat. However, it also stopped quite a few other items from going over the sides in that time . We fitted white but by the 4 year point it had rotted to the point you could break it with your arms. I think next time we will choose black to see if it will resist UV any better.

The black may also be more aesthetically pleasing. For some reason few yachts rafted alongside us when we had white netting up, guess some folk really don't like the thought of being near noisy children.

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Old 16-07-2018, 06:50   #138
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

So an update to this.


We have actually done the live man overboard recovery exercise discussed above.


I HIGHLY recommend doing this. It is eye-opening and extremely educational.



We did it in the icy waters of one of the fjords of Eastern Iceland, quite near the Arctic Circle.


As expected, it is quite a bit harder to get the casualty on board than you might think, and the practice is extremely useful.


We did it five times -- everyone on board got into the water -- and we learned something new and useful every single time we did it.


Some things we learned:


1. The life jacket makers warn you not to use the harnesses for lifting. Why are they there, if not for lifting? WTF? Well, I'm here to tell you, they are not. We broke the crotch strap buckle in the life jacket we were using for practice. I haven't figured out yet what to do about this, but it is a definite issue.


2. Even in a practice, not a surprise exercise, in calm weather with no danger, it is surprising how easy it is to screw up simple things like rigging preventers and even unwrapping ropes. All this stuff really needs practice, and we're going to do this again.


3. Theory did work at least that throwing a rope through a low friction eye strop cow hitched to the end of the boom and led through a cleat to a powered winch does the job of lifting by the preventered-out boom. The powered winch is strong enough to do it without any purchase, the rigging of which would cost precious time.


4. People float nicely in their drysuits, even without a life jacket, and it's comfortable even in icy water. No one got any water inside the suit and no one felt cold. This is a killer app for high latitude sailing.


5. I've practiced before with the life sling, but it was good to be reminded that this is quite awkward and probably dangerous compared to a proper harness. You really need to rig an additional sling to go behind the knees for this to be reasonably safe in rough weather.


6. It was fun!!





We also practiced recovering unconscious victims using a designated rescue swimmer. In the artificial, calm conditions of the exercise, it worked very well. In rough seas it will be challenging, but I think our chances of success are already significantly better after practicing it.
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Old 16-07-2018, 08:10   #139
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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We have actually done the live man overboard recovery exercise discussed above.

I HIGHLY recommend doing this. It is eye-opening and extremely educational.
Your recommendation is very welcome. I feel guilty of having been too lazy. I recommend these exercises to us and others.

Quote:
5. I've practiced before with the life sling, but it was good to be reminded that this is quite awkward and probably dangerous compared to a proper harness. You really need to rig an additional sling to go behind the knees for this to be reasonably safe in rough weather.
We recently got a practical idea and connected our towed rubber dinghy to the 50m rear anchor rode. Now we can release the dinghy quickly, use it a bit like a life sling (= sail around the swimmer and bring the dinghy next to him). We can also put one of the crew in the dinghy, or let the swimmer climb up to the dinghy himself. I wonder if this will work in real life. Not necessarily easy in a storm. As you can guess, also this procedure has not been practiced properly yet.
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Old 16-07-2018, 09:04   #140
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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. . . We recently got a practical idea and connected our towed rubber dinghy to the 50m rear anchor rode. Now we can release the dinghy quickly, use it a bit like a life sling (= sail around the swimmer and bring the dinghy next to him). We can also put one of the crew in the dinghy, or let the swimmer climb up to the dinghy himself. I wonder if this will work in real life. Not necessarily easy in a storm. As you can guess, also this procedure has not been practiced properly yet.

I have recovered a MOB into the dinghy. It works very well PROVIDED the weather is calm enough for the dinghy to be at all usable. The threshold of this depends on the dinghy, but I think few dinghies will be usable for anything over F5.


Nevertheless, if the dinghy is handy in the davits or even handier, being towed -- this might be the quickest and best way to do it. Good suggestion!


Another calm weather recovery method is the swim platform. I as MOB was recovered this way, some years ago. But for this to be safe requires REALLY calm weather. The transom of course is a death trap for a person in the water when there is any kind of wave action. So the dinghy will be better over a wider range of conditions.


We practiced recovering midships because that is the only place you can do it over a certain sea state.
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Old 16-07-2018, 09:23   #141
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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We practiced recovering midships because that is the only place you can do it over a certain sea state.
Yes, that's important. I'm planning to check how the dinghy works at midships. If people are not in good physical condition, we may need the prevented boom too.
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Old 16-07-2018, 16:06   #142
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

Dockhead,

Thanks for all the great rescue info, more people should try it. Our MOB practice day will be this Thursday, the first day out of port on our way up to Canada. I don't find the transom to be as much of a "death trap" at least on our style transom with a low sugar scoop, but we will try also using a halyard for midship recovery. Since our topping lift was strong enough to lift the 900lb generator into place below decks without a problem, it should be up to the task of lifting even the heaviest among us, it's also the way we hoist the sails onboard.

After you broke the crotch strap, what was your solution? I have climbing gear onboard in Italy, but not here in Maine. Did you use something similar to lower a crew member down to the MOB and attach a line to his harness? I also purchased a 7mm Aqualung wetsuit today, just in case I need to get in the water up around Newfoundland, and went ahead and bought one of those one piece polartec undergarments for my Ocean Rodeo Ignite drysuit. How do you like the drysuit?
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Old 16-07-2018, 16:40   #143
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

I basically tell crew that if they go over the side in any sort of significant weather that the chances of successful recovery are less than 50/50. I’m not sure what they actually are but them understanding that it’s a significantly fatal situation is more than an ounce of prevention in terms of impacting their behavior.

I’ve done a fair amount of ocean racing on big boats and the consensus is that stopping the boat, turning it around, getting back to the last known or projected location and actually finding the person takes orders of magnitude more time than a casual estimate indicates. In the case of an 80’ race boat it was 3 hours. And that’s with an AIS beacon in daylight.

I like the new inflatable Dan Buoy. On the stern rail held on with a Velcro double sided strip with a tag on the end. To deploy just pull the tag like an outboard starter cord and it drops into the water. No fussing with the old rigid pole and float and weight. Try deploying one of those sometime and watch the precious seconds tick by.

If someone is lost in any appreciable swell, consider that they will be visible less than half the time, only at the crest of a swell. And you have to be looking there when they are visible. At night? Good luck.

TL;DR...stay in the boat because your chances of recovery, regardless of equipment or practiced procedures are not confidence inspiring.
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Old 17-07-2018, 04:38   #144
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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Originally Posted by Kenomac View Post
Dockhead,

Thanks for all the great rescue info, more people should try it. Our MOB practice day will be this Thursday, the first day out of port on our way up to Canada. I don't find the transom to be as much of a "death trap" at least on our style transom with a low sugar scoop, but we will try also using a halyard for midship recovery. Since our topping lift was strong enough to lift the 900lb generator into place below decks without a problem, it should be up to the task of lifting even the heaviest among us, it's also the way we hoist the sails onboard.

After you broke the crotch strap, what was your solution? I have climbing gear onboard in Italy, but not here in Maine. Did you use something similar to lower a crew member down to the MOB and attach a line to his harness? I also purchased a 7mm Aqualung wetsuit today, just in case I need to get in the water up around Newfoundland, and went ahead and bought one of those one piece polartec undergarments for my Ocean Rodeo Ignite drysuit. How do you like the drysuit?



Have fun -- we had a great time doing our recovery practice.



I love the dry suit, and the killer app is the buoyancy regulation. I'm not sure I even need a life jacket with this. I was bone dry after half an hour in the drink. And I was able to swim a bit even.


For the rescue swimmers -- we didn't lower them -- they jumped in with a line attached, and then got hauled out afterwards (actually one of them was so athletic that she was able to pull herself onboard over the rail, herself!). Just going into the water seemed like the right way to do it. I'd be interested to hear if anyone has any knowledge or expertise about the best way to do this. If we lowered the person, then yes, a climbing harness would seem to be the best way to do it.


As to the crotch strap problem -- we haven't figured out a solution yet. I am very disappointed in this. Does anyone have a suggestion? We could attach supplementary rope slings I guess. They should be made properly in the first place






As to the transom -- be careful about this. The "transom hammer effect" has nothing to do with the form of the transom. It has to do with the motion of the sea under the transom. Dashew and others write about it, and you can see for yourself if you observe your own transom when the boat is stopped when there is any wave action. Basically, the sea goes up and down, the transom doesn't, so a person in the water can get hammered (and actually killed) when the transom comes down. In short, stay away from the transom in any wave action! Recover MOB's amidships except in very calm weather.
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Old 17-07-2018, 12:21   #145
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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As to the crotch strap problem -- we haven't figured out a solution yet. I am very disappointed in this. Does anyone have a suggestion? We could attach supplementary rope slings I guess. They should be made properly in the first place
Some vests seem to be strong enough. (https://www.spinlock.co.uk/en/catego...ps/deckvest-5d)

Also dry suits could include a harness that is strong enough for lifting. Or maybe a separate harness would be a good enough solution in this case (since it takes quite a lot of time to put the dry suit on anyway).
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Old 17-07-2018, 13:30   #146
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

Quote:
Originally Posted by Dockhead View Post
So an update to this.


We have actually done the live man overboard recovery exercise discussed above.


I HIGHLY recommend doing this. It is eye-opening and extremely educational.



We did it in the icy waters of one of the fjords of Eastern Iceland, quite near the Arctic Circle.


As expected, it is quite a bit harder to get the casualty on board than you might think, and the practice is extremely useful.


We did it five times -- everyone on board got into the water -- and we learned something new and useful every single time we did it.


Some things we learned:


1. The life jacket makers warn you not to use the harnesses for lifting. Why are they there, if not for lifting? WTF? Well, I'm here to tell you, they are not. We broke the crotch strap buckle in the life jacket we were using for practice. I haven't figured out yet what to do about this, but it is a definite issue.


2. Even in a practice, not a surprise exercise, in calm weather with no danger, it is surprising how easy it is to screw up simple things like rigging preventers and even unwrapping ropes. All this stuff really needs practice, and we're going to do this again.


3. Theory did work at least that throwing a rope through a low friction eye strop cow hitched to the end of the boom and led through a cleat to a powered winch does the job of lifting by the preventered-out boom. The powered winch is strong enough to do it without any purchase, the rigging of which would cost precious time.


4. People float nicely in their drysuits, even without a life jacket, and it's comfortable even in icy water. No one got any water inside the suit and no one felt cold. This is a killer app for high latitude sailing.


5. I've practiced before with the life sling, but it was good to be reminded that this is quite awkward and probably dangerous compared to a proper harness. You really need to rig an additional sling to go behind the knees for this to be reasonably safe in rough weather.


6. It was fun!!





We also practiced recovering unconscious victims using a designated rescue swimmer. In the artificial, calm conditions of the exercise, it worked very well. In rough seas it will be challenging, but I think our chances of success are already significantly better after practicing it.
You are to be congratulated on not only thinking through this, but actually DOING it.

Couple comments from my experience. (both Yachting, and i'm ex: navy)

Lifting with Lifejackets: You need to use the ones with a lifting strop on them, not lift from the harness point. Those lifting points are on the back of the neck normally. (Such as the Spinlock Deckvests). HOWEVER, as I'm sure your SAR friend pointed out, whilst a good spot to lift from, it isn't at all great for the casualty medically.

Swimmer in the Water. For a fully crewed boat who has practised this, it is fine and a very good idea. For interest, a designated rescue swimmer is standard practice in the Navy when conducting some operations where there is an increased risk of someone going over the side. (On small or larger vessels or Yachts). This is something that works very well, with several caveats.

1. The rescue swimmer needs to be properly trained, equipped, and be a highly competent & fit swimmer.

2. It is generally NOT the person-in-command, for any number of obvious reasons. Would they be willing ? I'm sure, should they ? heck no. Despite what someone insinuated on this thread, Skipper doing it is 'not-a-g-ood-plan (tm)'

3. Gear and procedures to ensure the swimmer can't become a second casualty. (Or at least, significantly reduce that risk)

4. Staying on the boat, and getting someone out of the water, are totally different topics. Of course everyone wants to STAY ON the boat.

MOB procedures are totally different for a fully crewed boat, and one sailing short-handed. A short-handed crew, such as ours, has to accept different risk profile, and carry out tasks accordingly.

Realistically, a swimmer is quite likely the ONLY way to get an uncooperative casualty out of the water, or even to get one out in the medically best position of Horizontal.


Again, Well done to Dockhead and crew for actually testing this for real, in Arctic waters. I'm familiar with Icelandic waters and they are... chilly !

Regards

Mark.
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Old 17-07-2018, 13:51   #147
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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Some vests seem to be strong enough. (https://www.spinlock.co.uk/en/catego...ps/deckvest-5d)
.
I don't think so. Those quote iso 12402 in their specs, and that iso (the last time I looked at it) has weak specs for the crotch straps - requires really only enough to hold down the inflation bladder.

and looking at the details, the crotch straps have plastic buckles, with likely no more than 95lb strength (there are two of them, but one can carry majority of load in the real world with slightly imperfect fitting)
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Old 17-07-2018, 14:03   #148
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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I don't think so. Those quote iso 12402 in their specs, and that iso (the last time I looked at it) has weak specs for the crotch straps - requires really only enough to hold down the inflation bladder.

and looking at the details, the crotch straps have plastic buckles, with likely no more than 95lb strength (there are two of them, but one can carry majority of load in the real world with slightly imperfect fitting)
I'm not really familiar with these vests, nor am I an expert in this area in general. I just noted that in the instructions pdf they say: "13 Lifting Loop - Easily located for lifting from the water during rescue and as a buddy loop whilst in the sea." Just wondering how we should read that.
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Old 17-07-2018, 15:35   #149
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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I'm not really familiar with these vests, nor am I an expert in this area in general. I just noted that in the instructions pdf they say: "13 Lifting Loop - Easily located for lifting from the water during rescue and as a buddy loop whilst in the sea." Just wondering how we should read that.
Yea, I know - there was a small fuss about that after the S/V Lion incident (UK skipper died when he went overboard with a spinlock vest with these crotches straps and they opened when his crew tried to lift him).

Spinlock says the buckles 'should' hold 50kgs (each), which they say is enough (with 2 of them) to lift someone (so long as the boat is stopped and there is no towing water force). But #1 those buckles in actual practice often open somewhere between 20 and 40kgs, and #2 it is quite possible that one buckle will take most of the load (while spinlock assumes they equally share the load), and #3 even in the most optimistic case of (spinlock's assumption of 100kg breaking strength with two of them) that is not at all enough safety factor for any life-saving equipment in any other application.

ISO has had a working group looking at this since like 2008 but they have basically punted on it - which means spinlock can essentially claim whatever they want (until someone sues them on it). The basic problem is that to meet any reasonable sort of life-saving safety factor the crotch straps would have to be much more substantial than they are now (much closer to a climbing harness), and that would add cost and wearing hassle and the mfg's don't want to do it because they (say they) believe it would reduce wear rates.

I have never tested one of these . . . but I would guess would be rather better than the plastic ones https://lowealpine.com/us/25mm-loadl...trap-x-1m-x1-1 and close to a 'drop in' replacement and reasonably light and not bulky. Still surely not up to fall protection standards.
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Old 18-07-2018, 00:00   #150
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Re: MOB Gear -- Are Dan Buoys and Life Rings Still Relevant?

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I have never tested one of these . . . but I would guess would be rather better than the plastic ones https://lowealpine.com/us/25mm-loadl...trap-x-1m-x1-1 and close to a 'drop in' replacement and reasonably light and not bulky. Still surely not up to fall protection standards.
I think at least one of the vest manufacturers should make one model that is strong enough for picking crew from the sea. That vest could be a bit bulkier and heavier than others, but I think that would be doable, and the additional weight and uncomfortableness would not be too much. I'd start looking what the common practices are in harnesses and safety belts in mountain climbing, racing cars and aerobatic aircraft.
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