MOB Recovery solution

WindermereColvic

WindermereColvic

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MOB drill is all well and good if your casualty is conscious and can be manhandled back on board, but my concern is that the unfortunate crewman may be unconscious or exhausted and it would be beyond the remaining crew to pull them back onto the boat. My question is this, could I use a system made up from the blocks in the pic bellow, attached at one end to the toping lift/spinnaker halyard and the other to the unfortunates l/j harness to haul them on board? I don’t know if a 2:1 purchase would be enough, i think it might be a bit tricky to lift the 50kg that might be necessary to lift a waterlogged 100kg adult, so I suppose more would be better, and some of the end fittings look rather flimsy for lifting a human, although they are rated for mainsheet use so they must be able to take a fair bit of strain. Any thoughts or ideas re my system or better ways to recover MOBs. I bet their are some varied solutions out their so i look forward to hearing yours. Thanks, Matt
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What you have here is a four to one purchase. I use this ratio on my boat. attached to the boom. I have used it to recover a ten stone crewmember.......you'll be surprised how much the adrenalin rush helps in this situation.....however, He was conscious and able to climb aboard once I got him up and I'm not sure my wife could manage me without more purchase.
 
Did you read our MOB practice thread Here ?

This arrangement worked well but was much improved if you could get the line back on to a winch. The problem we found was that the ring on a LJ is hard to get to when the LJ is inflated. Some LJs have a separate lifting strap that pokes out of the top which is much easier to get to.

You can buy these billy arrangements already made up. Certainaly the jamming cleat was essential to give the personal hauling in a breather without dropping the casualty back in the water. I recommend a practice in calm conditions whilst at anchor or on a buoy. Actually doing it in a seaway in the heat of the moment would be testing to put it mildly.
 
The pulleys as pictured are indeed 4 to 1 purchase and are typical of mainsheet blocks. Mine are the same.
If they are used for the mainsheet it should be easy to disconnect the bottom and swing it out to hoist a MOB.

If the pulley with the cam cleat is on the bottom then your pull should be upward. This is somewhat more efficient than having it at the top pulling downward. The up pull on the friction aids in the lift. Howwever this would mean the bottom pulley and cleat being at the MOB harness so a short strop to bring the bottom pulley up higher when he is in the water would be good. That means however that as he gets higher you have to pull upwards from a higher position.
It all means that you should try it out under safe conditions. I guess your water is still a bit too cold. good luck olewill
 
I have a 4:1 tackle of the sort envisaged permanently made up and ready to attach to a spare halyard if required.
I have never lifted a casualty with this, but regularly lift my RIB which weighs about 250lb (with large engine and fuel) without needing a winch. It would be easy enough to take the line to a winch / windlass if the lifter couldn't manage without.
I've always put the cam cleat at the top. This means by bending my knees I can use my body weight rather than any muscles. Also, I can't see how I would get the bottom block high enough to get a casualty over the lifelines if the cam cleat was on the bottom.
 
Not sure, but I think the blocks in the picture are Barton rated at 300Kg SWL. Which would be sufficient for lifting an adult even allowing for snatching when the boat rolls as they leave the water - the stretch in the purchase will help here.

That is exactly the system I used for many years when sailing with kids. I kept it rgged all the time with a helicopter strop tied to the toerail with slippery hitches and lengths worked out so it would just lie on the surface when hitches were pulled without too much slack. Remember, overhauling those purchases in a 'panic' and with one block dangling overboard would be difficult.
 
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If they are used for the mainsheet it should be easy to disconnect the bottom and swing it out to hoist a MOB.


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Easier to keep it as a separate set. We used the main sheet which I have attached by a snapshackle at the bottom but that wouldn't be practical unless the sail was properly stowed.
 
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Also, I can't see how I would get the bottom block high enough to get a casualty over the lifelines if the cam cleat was on the bottom.

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If one end of your lifelines are attached by cord then simply cut the cord and drop the lifelines. They can always be reattached afterwards.
 
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Also, I can't see how I would get the bottom block high enough to get a casualty over the lifelines if the cam cleat was on the bottom.

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We did but it would be better the other way up for that purpose. The angle on to the winch is better with it at the bottom. Try it out - that's the answer.

If one end of your lifelines are attached by cord then simply cut the cord and drop the lifelines. They can always be reattached afterwards.

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To avoid all the blood going to the casualty's feet (in simple terms) you should raise him by combination of chest harness and a strop/rope under the feet/knees, body not too far from horizontal. Once the hoist is taking the main weight, it should be possible to do this.
 
<<<< To avoid all the blood going to the casualty's feet (in simple terms) you should raise him by combination of chest harness and a strop/rope under the feet/knees, body not too far from horizontal. Once the hoist is taking the main weight, it should be possible to do this. >>>

This is the technique used when hypothermia is likely to be a problem and should not normally be needed for a MOB recovery. The patient would be pretty much unconscious due to lowering of body temperature (not injury) before this method would be necessary.

Our mainsheet has a 6:1 purchase. We found it impossible to raise each other when pulling upwards and it proved equally impossible to arrange the free end to a winch without riding turns. However, when we turned the mainsheet over and pulled downwards, with the upper end attached to the boom, either of us could haul the other up. I keep a short strop, wrapped in padding, in a cockpit locker for recovery purposes. It fits well under a casualty's armpits.
 
Having been at the MOB recovery session that Moodysabre referred to above, we set up a dedicated 4 to 1 purchase system to be attached to the boom, with a block hooked onto a cleat to lead the line (from the boom end) to a winch. It can be set up in about 20 secs.

However, I think we all recognised that if there are only 2 of you aboard and one goes over the side, except in the most benign circumstances, getting him/her back on board would be impossible - it was hard enough at anchor!
 
With 6:1 purchase and a cam cleat at the top we didn't feel we needed to use a winch, although we tried it for interest. We found that the winch tended to pull the boom towards the centre line of the boat, making positioning it over the casualty very difficult.
 
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However, I think we all recognised that if there are only 2 of you aboard and one goes over the side, except in the most benign circumstances, getting him/her back on board would be impossible - it was hard enough at anchor!


[/ QUOTE ] I trust you've got a bathing ladder, easily lowered from within the sea? A safety device often forgotten, but very effective for conscious people in the water - the majority.
 
It doesn't take long for the hydrostatic pressure from the water surrounding the body to have a detrimental effect if they are lifted vertically from the water. As mention earlier in simple terms now that the heart as to work harder they may be a chance of a heart attack. If they are hypothermic there is a good chance someone would have to go in to help them as by that time they may be unconscious or not able to use there hands.
An excellent book by Michael Tipton http://www.humankinetics.com/products/showproduct.cfm?isbn=9780736002158 goes into some detail to explain how to survive.
I came across him because he was one of the experts on the Ouzo enquiry.
 
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I trust you've got a bathing ladder, easily lowered from within the sea? A safety device often forgotten, but very effective for conscious people in the water - the majority.

[/ QUOTE ] I agree that bathing ladders should be capable of being lowered by a man in the water. But most fixed bathing ladders are mounted on the transom, and with a sea running, the use of these carries its own risks - I think I've read of at least one drowning following a blow to the head from the stern of the boat.

My new sailing season resolution is to test Freestyle's person recovery procedure with a real person, albeit one dressed in a wetsuit. Ideally, every member of the crew should be able to use this to connect a spinnaker halyard to the casualty's harness.

Manoverboardtackle.jpg
 
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Hi, Whipper Snapper. You talk of a Helicopter strop,did you buy it or make it yourself. I am after one myself.

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Take a look at this thread.


(That took some finding - the search facility is useless. It kept hitting a completely different thread because the Google cache was different from the page it actually pointed to)
 
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But most fixed bathing ladders are mounted on the transom, and with a sea running, the use of these carries its own risks

[/ QUOTE ] Get rid of sails and go beam on to the sea, or heave to if your boat doesn't fore-reach too much. Both actions get rid of pitching.

Even if pitching, a moderately agile person easily copes with a F4 head on seaway - as long as the ladder steps reach at least a metre below the surface. I learnt about this the hard way when a hard sea breeze picked up after we had swum ashore, with the boat anchored in a Majorcan Cala.

The ladder itself stops you from going under the counter.
 
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