How strong a halyard for MOB retrieval?

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FinesseChris

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Plan is to attach a 6:1 handy billy to a masthead halyard, then lift unlucky POB.

For this, am replacing an existing light line to the masthead with a new halyard. What gauge do I need? 6mm? 8mm? Needs to be moderately comfortable to handle, as well as strong, I suppose.

Would welcome thoughts,

Cheers,

C
 
Even 6mm braid on braid has a working load of >1000kg. Your MOB may weight 150kg (if very large) + wet clothes of another 50kg - so any halyard would seem to be enough. Or a different way to look at it - for your halyard to snap through a load applied on the handy billy you would need to pull the equivalent of 166kg - which if you had that strength I doubt you would need the handy billy!
 
The halyard does not need to be comfortable to handle. You attach the tackle, hauling line on halyard block, hoist the halyard to a fixed height, attach bottom of tackle to MOB strop, lift person in on tackle.
I have an 8:1 rated for 5 tonnes. At 8:1 it is a piece of cake. Use ball bearing blocks and have the working end tail run through a ratchet block. This makes hoisting easy for the person doing the recovery.
My procedure.
1. Tackle is stored in a yellow pyrotechnic storage tub.
2. It is pre extended to the height needed and I use tape to cinch up the falls just below the block.
3. The POB lifting end goes in the tub first.
4. Manoeuvre along side POB and use their life saver, or secure a lifting strop to the POB, to secure to midship cleat. Nite all my life jackets have Lifesavers fitted to lifting strop.
5. Open box and connect halyard to hoisting block.
6. Hoist lifting tackle and when POB block Is almost out secure it to the guard rail or POB lifesaver, lifting strop. Correct side so it is not under guard rail.
7. Make off halyard.
8. Flip off POB line on cleat, or attach tackle to POB lifting point.
9 haul on board.

Why the ratchet. You will need to guide the POB with one hand, while lifting. Sitting on the deck, or kneeling, one handed operating is very easy using knees buttocks to stop line while you slide hoisting hand further up heaving part.

Obviously each boat, skipper needs to work out the best way.

Good luck.

Edit: stupid grammar mistakes and word correction required sorted.
 
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I’ve going a slightly different route on my boat. I have a main halyard that is long enough to reach the water, via the end of boom. The idea being the boom can be used as a crane/davit to lift mob over guard rail. The topping lift supports the boom and obviously a cabin top winch can be used to haul on the halyard. I just need to fit a cheek block to end of boom.
 
ylop said:
Even 6mm braid on braid has a working load of >1000kg. Your MOB may weight 150kg (if very large) + wet clothes of another 50kg - so any halyard would seem to be enough. Or a different way to look at it - for your halyard to snap through a load applied on the handy billy you would need to pull the equivalent of 166kg - which if you had that strength I doubt you would need the handy billy!
Click to expand...

I don't doubt your figures or conclusions, but would just point out -

1) that it is not the static load, but the dynamic load that would most likely be the maximum and the trigger for any failure - if for example the MOB is dropped a bit (or e.g slips/falls while clambering out), and is then arrested by the halyard.

2) the strength of the line will presumably deteriorate over time.
 
MontyMariner said:
Using a similar idea, I have snap shackles at both ends of the mainsheet blocks so that I can invert the mainsheet, swing the boom out to lift a mob.
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Good idea, but does your mainsheet have enough purchase to actually lift a MOB?

As I think is mentioned earlier, consensus seems to be 6:1 minimum, 8:1 preferable. Mainsheet on a smaller boat is unlikely to be so. (Also depends on whether you can additionally take the end of the line to a winch without undue complication.)

I also seem to vaguely recall some tests a few years back (can't remember now whether this was perhaps YM/PBO or a bunch of East Coast Forumites who met up to do practice/test MOB techniques) coming to the conclusion that it didn't work so well using the boom, and attaching a suitable purchase tackle from a masthead halyard was more effective. I think the issue with the boom was getting enough height to lift the MOB, and the hazard/complication of the boom swinging about.
 
With the boom and mainsheet getting the casualty over the guard wires may be tricky. Say the bottom of your boom sits 1m above the top of your guard wires? Through that 1m "gap" you need to fit the mainsheet blocks etc, the lifting becket/sling you are using, the casualty themselves... perhaps doable if well manned. If not well manned, then if MOB is most likely when sailing you probably need to get the main down and under some sort of control or using the boom will be a nightmare both for safety of those on deck and control of the boat.
 
My default halyard to raise the MOB lifting tackle is the spinnaker halyard because it’s on a swivel block at the mast head.

One person can retrieve the MOB and move them around the side deck, even lowering through fore hatch, or main hatch on my centre cockpit.

It takes less than two minutes to rig up.

The hard part of the MOB recovery is securing the MOB once along side. Many boats have high freeboard and reaching down to connect to the lifejacket’s lifting strop, is very difficult. This is why I use Lifesavers on all my life jackets. They float free when the lifejacket inflates and can be easily hooked up with boat hook and secured to the boat, ready to be used to lift the casualty in.

They are an easy solution to an awkward problem, and I always recommend them in this type of discussion.

MOB Lifesavers | MOB Retrieval for lifejackets

I have no association with the company except as a customer.
 
I have my rigid dingy stored on deck while on a passage and use my spinnaker halyard and spinnaker pile to hoist the dingy over the handrails onto the into the deck supports.

The halyard is 12 mm so would be strong enough to lift a MOB.

I use the mast winch to lift the dingy so should be good enough to lift a MOB

I also have a targa at the stern to lift dingy using my cockpit winch to lift a MOB out of the water and on to deck
 
The halyard is not the problem, not should be getting the boat back stopped alongside the MOB. The problem is getting the MOB secured to ANYTHING., and then getting him/her back.

The classic answer is the spinnaker halyard to a mast (or led back coachroof winch), but the main halyard will work too as long as you can achieve 150 Kg+ upwards pull at the bottom end. Genoa halyard basically useless on 98% of boats, and anyway the lead is bad. On smaller boats you usually have less freeboard so less of a problem.

IMHO ignore all the "you must lift he MOB horizontally" with fancy bits of kit. What you must do is get him/her back on board - somehow and preferably quickly. This thread is the first I have heard of the "lifesaver", but it looks a very good idea..

I have spent a whole day on two different boats practicing MOB with a hulking great Navy diver as the in the water caualty. On one occasion he terrified me by lying inert face down for about 3 minutes. The problem became STOPPING crew members from jumping in untethered.

On the getting back, reach-tack reach was totally reliable, but slow. Crash stop worked beautifully on a fin and skeg cruiser, but repeatedly totally failed for everyone including a ridiculously highly qualified Extra Master and Yachtmaster Examiner. on a much more flighty racer.

A few years later prior to an ocean race I ran a MOB exercise for several crews. A lecture one evening at the club, when everyone thought it couldn't be that hard. Next day with two super fit teenagers as victims, we started by practicing moored to a pontoon. Most crews got it to down to under two/three minutes, with no sails up. With the victim playing unconscious, it took longer, and somoene else always had to go into the water to secure them. This on high freeboard boats.

Then we did it under sail, with me shadowing in a RIB. Even after practice, and knowing one of the teenagers was going to "fall off" (usually with a piercing scream and a big splash) it usually took 5-10 minutes. from splash to aboard again. When on the way back to the club, spinnaker up, one slipped quietly overboard minus dramatics, it took about 20 minutes to get him back.
Thay had a good guess about the location of the MOB from me in the RIB .....
 
I like the idea of using the boom as a crane, however controlling the boom would need some careful thought. MOB in any seaway will cause some pretty horrid rolling, meaning the boom will have to be stopped from swinging somehow.
 
What you must do is actually try top retrieve an MOB onto your boat. You may well be dismayed at how hard it is even after you plan a lifting system. As said any halyard should be fine. You will need a tackle as typically using the halyard onto a winch (no tackle) involves a lot of friction. as said tackle must be stowed stretched out to full extend.
That "lifesaver" idea seems good for a LJ with harness. It should not be too difficult to connect a loop of nylon /polypropylene rope to harness and tucked into place where bladder is. hopefully it will float out and can be captured by boat hook. At our club mainly for dinghy rescue we have provided each rescue boat with a Buoyancy vest. To be worn by any rescuer who needs to get into the water. Buoyancy vest meaning you can swim and work effectively but with buoyancy.
Search MOB on this forum for practical ideas on MOB recovery. ol'will
 
Over the years I have run two MOB recovery practice sessions with a group of boats on moorings with a good tide running and volunteers in the water. I recommend it. You can try all your ideas and see how hard it is.

A billy on the end of a spinnaker halyard with the billy line back to a main winch worked fairly well. Of course this doesn’t replicate doing it in a seaway whilst also boat handling, particularly by a less strong and experienced crew.

There was a write up on here about the day and the only sensible conclusion was not to go overboard. Apply your thoughts to harnesses and jackstays and not getting hit by the boom. A conscious and helping casualty is hard enough - an unconscious one would be almost impossible unless you had a good size crew to assist.
 
MontyMariner said:
Using a similar idea, I have snap shackles at both ends of the mainsheet blocks so that I can invert the mainsheet, swing the boom out to lift a mob.
Click to expand...
How would you stop the boom crashing about in a seaway if disconnect mainsheet? With weight of dropped sail ours would be a danger unless got prefitted gybe preventer ropes as well ready to go.
 
The ideas of using the mainsheet tackle seem to ignore the fact it probably has a sail attached to it. You have to drop it or furl it before you can deploy the mainsheet.
Two handed, as many are, you will probably have lost sight of the MOB by the time you have done that.
The same reservations apply to the use of halyards.
I use my main halyard to hoist the mainsail.
I use my Genoa halyard to hoist the Genoa.
Neither are available.
Because I am a slave to redundancy, I have a trysail halyard and a storm jib halyard either of which I could use and two speed mast winches.
My biggest fear is losing sight of the MOB.
I like the idea of dropping a tethered buoyant line with a life ring at the other end and circling the MOB.
Rests well with an immediate heave to which kills all the noise at the same time.
 
FinesseChris said:
What gauge do I need? 6mm? 8mm? Needs to be moderately comfortable to handle, as well as strong, I suppose.
Click to expand...
6mm might well be strong enough but I would suggest you need 8mm to be comfortable to handle even if you use a handy billy and or winches. Just try and see how much 6mm digs into your hands even in the warm and dry, factor in wet and cold and the thinner line is about unholdable let along pullable on.
 
Sad accident just two days ago, a man fell overboard and despite being tethered the other three persons were unable to lift him out of the water. Not many details on the article, it says there was some swell which made things difficult, even a fishing boat was unable to lift him as they feared to hit him. Eventually the SAR arrived, one of them went in the water to cut the tether, once they got the casualy onboard they could not ressuscitate him

Un homme de 70 ans meurt noyé au large de Belle-Île
 
FinesseChris said:
Plan is to attach a 6:1 handy billy to a masthead halyard, then lift unlucky POB.

For this, am replacing an existing light line to the masthead with a new halyard. What gauge do I need? 6mm? 8mm? Needs to be moderately comfortable to handle, as well as strong, I suppose.

Would welcome thoughts,

Cheers,

C
Click to expand...
Just for info - It is usual to allow 250Kg for a MOB
 
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