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Old 11-08-2022, 22:51   #1
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MOB safe options

Hi Cruisers,
I'm a new member with a 5 yr plan
my other half has put to me the fear of being in the water for a long period if she ever fell overboard while im asleep.
I've assured her that there are safe guards like tethers, eperbs, PABs, flares, but in my admitted limited experience got me to thinking, if the life jacket had a remote device which turned the helm say left so the boat went in a circle to return to the same place what would be the effect and would it be possible, and what would be needed to make it possible. and yes i know rule number 1 is don't fall off in the first place.
thanks for your thoughts
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Old 11-08-2022, 23:48   #2
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Re: MOB safe options

There are MOB alarms that will sound off if the device moves out of a pre-set range I.e. fall over. I'm not crazy on the idea of turning the boat, particularly if sailing. Maybe turn into the wind ?

I'm a big fan of laser pointers on life jackets, the MOB is more likely to know where the boat is to point the laser at the boat than the boat is likely to know where the MOB is. I am in the minority with that idea, every time I bring it up I get shot down on here. So it's just me and the Australian Navy that like lasers for MOB 🙂🤣🤣🤣🤣😂🙂
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Old 12-08-2022, 00:59   #3
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Re: MOB safe options

As Dave_S said, what you want is an AIS MOB.
This is activated when your PFD inflates and sets off an alarm on your VHF (and also other boats in range).
It also shows the now-awake person where you are.

Once itís installed you donít notice the extra weight.

This system does rely on:
You wearing your PFD.
Setting up the system with your MMSI.
The other person/people on the boat knowing how to to come back and get you.
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Old 12-08-2022, 04:03   #4
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Re: MOB safe options

It's not just one task. Consider the issue as part of a complete scenario. It starts with one person on deck and one below asleep. I continues through preventing a fall into the water, to spreading the alarm, to finding the person, to getting to them, to getting them out of the water while hypothermic. Design in layers of "plan B" at each stage.

I like the laser idea - so much better than a twinkle light on a PFD.
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Old 12-08-2022, 04:52   #5
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Re: MOB safe options

Sailing Project Atticus (Youtube sailors) has an episode where they explain their MOB system. It works kind of like an anchor alarm. Crew members have a sender on their PFD. The boat has a sensor. When the sender and sensor are x-feet apart (you set the appropriate distance) an alarm is triggered.

Honestly, though IMO this alarm system is more for psychological effect (in this case -- your wife's peace of mind) than real world practical application.

Over the years, I've thought about this scenario alot. My wife and I have practiced MOB drills. A MOB rescue is difficult at best even with several crew members assisting, relatively calm seas, and good daylight visibility.

Change the situation to only one crew on the boat (your wife), 5'+ waves, poor visibility, and "difficult" becomes nearly impossible.

Try this experiment: Go out in rolly seas. Have your wife pretend to be asleep down below. Toss a 150lb bag secured to a pfd overboard. Yell down to your wife that you've fallen overboard. Then sit back and watch to see how successful she is at "rescuing" the bag all by herself.

The MOB alarm theoretically will alert her to the fact you've fallen overboard. It will theoretically mark your location so that she can return to that spot -- after she has pulled on her PFD, climbed into the cockpit, tried to make visual contact with you, started the engine, dropped the sails (solo), turned the boat around, and returned to your location. Now comes the fun part: With your 10-ton (??) boat with maybe 5' of freeboard bobbing up and down in the waves, and the 150lb (i.e. "you") victim bobbing up and down in the waves, your wife has to haul that load up over the lifelines onto the deck. Depending on your condition, she possibly/probably will have to do that all by herself with no assistance (or limited assistance) from you.

Would it be possible for her to pull that off successfully. Of course.

Would it be likely for her to pull that off successfully. I have my doubts.

So (and this is just one man's opinion on an opinion forum) my best advice would be (as you have already pointed out): don't fall overboard in the first place.

Bob
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Old 12-08-2022, 13:01   #6
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Re: MOB safe options

Brenmuhl said: "...if the life jacket had a remote device which turned the helm say left so the boat went in a circle..."

Boats are NOT cars! What you are proposing will not work because a number of realities militate against it:

If you apply a fixed deflection of the rudder the boat will NOT return to the point where you applied the deflection. Set and Drift prevent it. That is true of a power boat and even more true of a sailboat. A sailboat coming about or wearing will NEVER follow a circular track over the ground!

If someone goes overboard you will have a very, very hard time even seeing that person's head in the water if there is so much as a ripple, let alone any amount of wave.

If is VERY unlikely that a single person left aboard can even get the MOB up and over the rail back into the boat without mechanical help.

In our waters life expectancy is 40 minutes for a person of "normal" fitness that's gone overboard. Muscular coordination and control becomes problematic after ten minutes, meaning that the MOB can make very little contribution to his own rescue.

The best thing you can do for your wife is ensure that she will never go overboard. That can be achieved by her staying ashore or by your locking her up in the cabin :-)!

A device that every boat should have is a "Jacob's ladder" - a ladder made with rope flanges but with iron pipe steps that you can hang over the side. It can be rolled up and stows easily. It must reach down far enuff that the lowest rung is five feet or five-foot-six below the surface of the water so a MOB can get his feet on it. Rungs can be about a foot apart, but, as I said, after ten minutes in our kind of water, it is doubtful that a MOB would have enuff strength left to climb it unaided.

The rungs HAVE to be iron pipe so the ladder will hang straight down. Wood doesn't cut it! It would float making the ladder useless.

An old, old technique for getting a MOB up and over the rail, is to drop the main, slip it from it's tracks on the mast and let it fall over the side with the halyard still attached. You then maneuver the MOB, who might well be unconscious, into the bunt of the sail, heave away at the halyard - you probably would have to use a winch - and the MOB will parbuckle up the side of the boat and over the rail or the lifelines.

Would work with in-mast roller furling would it :-) The other thing you have to have to use this technique is a PROPER running topping lift. So don't have in-mast furling if you are gonna go cruising just the two of you!

Cheers

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Old 12-08-2022, 14:14   #7
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Re: MOB safe options

In my view: you fall off then there's a very high chance of death, especially so if you're the only one on deck and/or sailing in cold water or in darkness at the time. Add in factors like running under Auto Pilot, under sail, wind/sea state, distance from shore, success chance reduces and becomes much worse.

And if the MOB procedure hasn't been practiced (and on many boats there's not even a plan), then expecting success if the real situation arises is most unlikely to end well.

A boat sailing at 5 knots is 1 nautical mile away in 10 minutes. That's a long long way. Bobb_Lex's suggestion of trying to retrieve a weight is good, but here's another test. On a pleasant sailing day, say 10 knots of wind, tie a weight to a fender so that it will float but not be blown away, and throw that overboard, sail on for just 5 minutes, turn around and then try and find the fender. The fender representing your crew mate's head. You can could add a light to the fender and try exercise this at night.

I actually like the OP's idea of turning the boat. In reality the main problem is disabling the auto pilot or wind vane; stop the boat! Every moment that the boat sails/motors away is increasing the risk factors. So stopping that boat at the earliest moment is vital for a positive outcome.

Trentipeids makes the point that boats aren't like cars. Sure but what all boats, at least under sail share is that, unless in storm conditions, the yacht can at least be put in irons and so not sail further away.

Oh and by positive outcome that might just be body recovery. For the family, and one's estate, having a body is very significant. And of course where there is a death, or where the body is not retrieved, than there will be a Police investigation, and there are examples of this scenario that eventuated with a manslaughter or even murder charge.
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Old 12-08-2022, 16:29   #8
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Re: MOB safe options

If you can maneuver your boat to a beacon in the distance you can get back to a person in the water. I watched an Australian Navy SAR where they used lasers. They were 10-20nm away (several lasers in different positions) at night with a lot of city background light from my position. I could clearly see blue and green lasers at that distance when they were pointed in the sky, the red and yellow still visible but to a significantly lesser extent. I imagine without the background light the blue and green would be visible well beyond double that distance, particularly the blue.

Assuming the MOB is alert, and I know a lot of doomsayers will say most aren't but I'd dispute that in warm water. If they have the laser pointer pointed anywhere in the 60į cone above them you will be able to get to them.

Then, the hard part, you have to have a way of getting them on board. A cat is much easier than a mono. Some planning with the equipment you have and I'm sure you will figure it out. It might not be pretty and probably some injuries but highly likely in one piece. I think the tender lift or the topping lift are worth considering depending on the layout but spend some time looking at all the possibilities on your boat thinking of both smooth and rough weather you will probably need a different plan for different conditions.
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Old 12-08-2022, 19:17   #9
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Re: MOB safe options

Quote:
Originally Posted by brenmuhl View Post
Hi Cruisers,
I'm a new member with a 5 yr plan
my other half has put to me the fear of being in the water for a long period if she ever fell overboard while im asleep.

She's right. MOB survival rates are less than 50%, and most of the success stories involve race boats with large, athletic crews.
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Old 12-08-2022, 19:55   #10
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Re: MOB safe options

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She's right. MOB survival rates are less than 50%, and most of the success stories involve race boats with large, athletic crews.
I wonder how many of these are single handers and how many were poorly prepared. I imagine excluding those two possibilities would bring those numbers way up to an acceptable number.
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Old 12-08-2022, 20:39   #11
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Re: MOB safe options

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Originally Posted by ChrisJHC View Post
As Dave_S said, what you want is an AIS MOB.
This is activated when your PFD inflates and sets off an alarm on your VHF (and also other boats in range).
It also shows the now-awake person where you are.

Once itís installed you donít notice the extra weight.

This system does rely on:
You wearing your PFD.
Setting up the system with your MMSI.
The other person/people on the boat knowing how to to come back and get you.
One more thing about an AIS beacon. It also relies on your boat having AIS receive capability. If not, the MOB will only be visible to another vessel with that capability that is within the rather limited VHF range of the personal AIS beacon.

Consider also a Personal Locator Beacon. That transmits to the SAR satellite.
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Old 13-08-2022, 02:58   #12
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Re: MOB safe options

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Originally Posted by slipaway View Post

Consider also a Personal Locator Beacon. That transmits to the SAR satellite.

When out kayaking I have a PLB on my PFD, with the lanyard attached to the shoulder strap. Kayaking I'm not really doing long passages, a few nautical miles at most, and I wear a dry suit if the water i cold (Baltic or northern Scandinavian lakes...). Add two lights, one on each shoulder, and the SAR team should be able to retrieve me before hypothermia. My paddling PFD has a "strong loop" than can be used to life me up.


As I get more into cruising (single-handed) with a sailboat my plan[TM] for any offshore trips is to have a 30m floating line with a float trailing behind. Now, I'm not a circus strongman, so I intend to either have knots every 30cm or so, or two lines tied into a simple "ladder" (also: a carabiner in the end of the rope, so that I can clip in). I figure that even I could "climb" that towards the transom, and the the line is naturally tied off near the swim ladder so that I can then climb aboard. The trick I learned when doing swift water rescue training is to float on my back and pull any lines over one shoulder: much more comfortable than face down.



Planning to perform a practical test with someone useful left aboard, and a safety line that can be used to winch me in if I fail.
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Old 13-08-2022, 03:14   #13
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Re: MOB safe options

Quote:
Originally Posted by ParL View Post

As I get more into cruising (single-handed) with a sailboat my plan[TM] for any offshore trips is to have a 30m floating line with a float trailing behind...

Planning to perform a practical test with someone useful left aboard, and a safety line that can be used to winch me in if I fail.
I think that you will be discouraged by the results of this practical test.

Bob
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Old 13-08-2022, 03:25   #14
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Re: MOB safe options

If you're overboard as a single hander, too late. Best wear a pfd with D rings and clip in with every move, and even more so when it's calm. We develop a false sense of security when it's calm and a trip or stumble due to inattention and you're overboard.
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Old 13-08-2022, 05:31   #15
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Re: MOB safe options

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Originally Posted by Dave_S View Post
I wonder how many of these are single handers and how many were poorly prepared. I imagine excluding those two possibilities would bring those numbers way up to an acceptable number.

Who knows. Some, for sure. ::shrug:: We lost one here five years ago who was motoring on a calm night on Lake Pepin. There was damage to a lifeline stanchion and the boat was found in gear with the engine running. His body was never found. The presumption is that the boat hit a log or some other underwater debris while he was relieving himself at the rail.



It is clear from the OP that they are a couple relatively new to sailing and that he is more enthusiastic than she is. I think it's an interesting question how many of the wives of sailors fitting that description could turn the boat around in the sort of weather that leads to MOBs and stop it alongside the MOB. Especially if on a run with the boom prevented out.
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