Safety and the MOB

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Moderator Emeritus
Jul 30, 2009
Vessel Name
Skinny Dippin'
Vessel Make
Navigator 4200 Classic
So I'm reading Gene and Katie's book: Coastal Cruising Under Power and just past the Chapter 12 covering safety. It mentioned that it's a good idea to practice your MOB procedure. That got me thinking about how that would relate to us in Skinny Dippin'. She's your run-of-the-mill 35' Taiwanese sundeck trawler (Senator brand) that the only way to get from in the water to onboard is via a 20" teak swim platform and up a steep ladder to the aft sundeck. Being that we have full intention to do a fair amount of cruising in our future as only a couple, what do you reckon would happen if we had a MOB emergency?

As I am 6.0' 195 pounds, if my 5.0' 100 pound wife may not be a huge issue to simply pull her onboard. But what if she's (or anyone) injured? What if I am the one that goes over? I don't see how she would have any chance of getting and unconscious, wet, 200 lb. dead weight into a place where first aid could be rendered.

Would a davit be in order? Could a simple block-and-tackle rig cantilevered off a sundeck support do the job? Looking for some ideas and opinions. Thanks!

-- Edited by GonzoF1 on Sunday 25th of October 2009 06:24:38 PM
As it sits right now, I think your only option would be to strap them to the swim platform!!!!
*** I would say the only way to get someone aboard that is incapaticated would be by a davit or a pot hauler. A pot hauler Davit would be the best in my opinion*as you can also use it to haul prawn/crab traps on board. ( Just The Fisher In me)

**** If a motor is used on the pot davit it would need to be able to pull the weight of a person your size on board. Don't forget the weight of wet clothing.**A block and tackle could*be set for a quick rig on the pot davit if the line hauler isn't strong enough.
**** A rope boarding ladder or a dive ladder off the swim platform could also be used If the sea is calm. A swim plat form rising and falling in 2 or 3 ft waves can be lethal.
** Check out the recomendations in Chapmans.*
**** Even with a davit rigged, check your*P.F.D. to be sure there is a strong place to hook onto the M.O.B.

-- Edited by skipperdude on Monday 26th of October 2009 09:55:04 AM
Check out the Lifesling system and get the 5:1 block and tackle that comes with it. Should be no problem to get either of you back aboard.
You have a mast and boom to retreive a M.O.B.
From looking at the picture of there boat would a Stanchon or rail mount be strong enough to retreive? I Think a boom or a davit would still be in order or as Gonso stated something rigged off the top. You have to get the M.O.B. high enough to get onboard.

I believe trying to use an existing stanchion or railing as an attach point for a Lifesling or other retrieval system would subject them to sideloads that would certainly bend them over if not pull them out of the deck altogether.

Better, I think to come up with some purpose-built attach point that will let you haul someone up the side of the boat. As Skipperdude said, you don't want to be messing around with an unconscious or semi-conscious person at the swimstep with the boat pitching and rolling, which is probably what caused the person to go over in the first place.

There are a variety of davits available that would work for your purpose. Some friends of ours installed one on their sailboat for lowering and retrieving the outboard motor they use on their towed dinghy.

I see your boat has a radar arch. Perhaps, if it is strong enough, that could provide an attach point for a retrieval system down the side of the boat.
Do you carry a dinghy? On your boat getting the dinghy into the water and the lifeless body into the dinghy may be the answer. Then you would at least be out of the cold water while help is summoned.
Otherwise, a tackle rigged from the highest strong point you can find, to a lifesling style lifering will get the body up the side of the boat to the deck. I don't think there are any stanchions on your boat strong enough for that job, so you will need to rig to the radar arch. A snapshackle onto a padeye on the side of the radar arch, up as high as your petite wife can reach, then hauling the mutipart tackle from the side deck where she can grab you as you rise from the water.
Practice it once to see if it is at all feasible. The result of your trial may be that you wear your PFD and harness a lot more, because now you have confirmed that going over the side will surely be fatal.
Yes. Actually, the dinghy is on Weaver Davits on the swim platform. Which, in and of itself, complicates the process even more.

I don't consider the radar arch to really be a feasible option. It's not only fairly narrow - possibly three or four feet inboard, but the hard sundeck cover it rigged to it where any MOB recovery rig will need to attach.

I know those boat cranes have a name, but I can never remember it. Help me out here folks :)... But I was wondering if there is a surface mounted one that can bolt to my sundeck roof and can support 200-ish pounds? We are planning on moving the storage of the dinghy up there anyway and may want to invest in one. However, I'd like to avoid something too big, heavy,,, and expensive. I was thinking of fabricating one on my own with thick-wall pipe and a trailer winch.

Any links to pre-fab ones would be great.
When my wife and I took a USCG Auxilliary boating safety course back in the mid-'80s after we bought our first boat, one of the classes was on the subject of hypothermia and MOB recovery. The person who taught that particular class was one of the leading physicians at the University of Washington Medical Center. Two things I most remember from that class is that a person in the water who is unable to help themselves get out (either from hypothermia or injury) is almost impossible for another person to get out of the water onto a swimstep, into a dinghy, etc. The weight, the angle at which the rescuer has to reach out at, to say nothing of the pitching and rolling of the boat, make it a virtually impossible task. The instructor had the class members try it on the floor of the classroom--- no water, no cold, no motion--- and no-one could do it.

The other thing I remember is that any viable plan to get a disabled person out of the water MUST include some sort of lifting harness or device that can be put onto the person while they are in the water (either by the MOB him/herself or someone else) and there needs to be a means to haul the MOB aboard that can be operated manually by one person. A direct pull won't do it, so some sort of mechanical advantage is needed. Give the weight involved and the typical strength of most people, a double-purchase block system is a minimum requirement, and a triple purchase is probably better.

-- Edited by Marin on Wednesday 28th of October 2009 10:53:39 AM
My $0.02:

My tender is stored above the aft cabin, and the hoist that lifts it off and into the water could certainly haul up a person.* There's a hand winch on it, and the cable will extend to the water.

The Lifesling is a good device, but I really can't imagine getting it around an unconcious*person in the water - especially with a rocking boat.*

I like the auto-inflatable PFDs with integral harness.* Not too bulky to wear around, if you go over there's at least a chance you'll float face-up, and now you have an attach point already on the victim to which to connect your hoist.** You can also use a jackline if you're moving around the boat.*

I'm enough of a fatalist (literally in this case) to figure on very little chance of survival upon going overboard in PNW water any time of year.* The initial immersion has a good chance of doing you in even before the hypothermia strikes.* The cold water will render you pretty much unable to assist in your rescue by the time the boat gets back around.

Coast Guard guy I spoke with up here told me the main thing the PFD does is to speed up the recovery of the body.
Chris Foster wrote:

Coast Guard guy I spoke with up here told me the main thing the PFD does is to speed up the recovery of the body.


Now THERE'S a cheery thought for the day.* :(
If another person is the MOB, the chances are high that I could get them out.* The first thing would be to throw out the life ring with 100 ft of rope behind the boat and circle the person so the ring is brought to them. *Like we do water skiing/tubing, pull them to the boat and then help them out of the water, either the swim step and/or the mast boom used for the dink.

However, if I was the MOB I would have to rely on mostly on myself.* When we leave the dock I sort of have everything set up/out just in case.* If it was just my wife and I, I doubt she would even notice until the boat ran a ground as she reads/naps most of the time.* *

For a Live Aboard in the PNW we face MOB every day right at the dock. In the warm summer months a person stands a good chance, but in the dead of winter with heavier winter cloths the chances are reduced.* Every year people die next to their boat tied to the dock.* In the 11years my wife fell in twice and I fell in once.* My wife was very luck both times as the first time our neighbor heard her and the second time I went looking for her.* With the adrenaline pumping I pulled her out of the water wet cloths and all.

The one time I fell in I was mentally prepared but still the shock of the cold water took my breath away, the winter cloths made it difficult to swim and the cold sap my energy.* Again if it was not for the adrenaline, I would have never have made it and that was about 8 ft from the dock.* Have you ever tired to get out of the water by your self on a low floating dock?* **

The dock captains had the Everett Marina install emergency ladders and life rings every 100 ft along the docks last winter. I also have a life ring and boat hook hanging on our dock steps.* ***The best is to prevent a MOB and/or to plan/rely on yourself as help may not be around.
So what do/have you done to prevent a MOB?

-- Edited by Phil Fill on Thursday 29th of October 2009 12:07:47 PM
Phil Fill wrote:

So what do/have you done to prevent a MOB?
To prevent an MOB we have the boat's relatively high hand rails, relatively wide walkaround deck, and numerous grab rails.* And neither one of us goes out on deck without telling the other person.

To recover an MOB should we ever have to, we have a LifeSling ready to deploy on the aft rail.* We retrofited our boom and mast with double-purchase blocks on the topping lift and boom fall to make it easier to launch and retrieve the sailing dinghy that's carried on our aft cabin, and this of course would make it much easier to haul a person aboard with the Life Sling.

We also wear manual/auto inflate life jackets, both of which have harness rings on them.* These, we were told during a USCG boarding, only meet the USCG requirements for PFDs if they are worn at all times when on deck.


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