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Re: MOB systems
delite, I don't understand your repeated reference to the boom as a danger. A boom is a boom, is a cargo boom, is a crane. That's how you reach out to lift things, and there's no reason it should endanger the crew or the MOB any more than a boom endangers everyone on deck at all times. Which it normally does, all of the time.
There are only three ways to approach a MOB in the water. You can try to back onto them, generally a bad idea since the prop is a pointy thing that likes to chew flesh, and you've got the prop and rudder and the stern is going to be bouncing up and down trying to kill the MOB unless you're in dead flat water.
If you've ever tried a stern boarding in the water, even in two foot seas, you won't want to be recovered that way.
So then you can approach the MOB from either upwind or downwind and try to recover them miships, which is how NOAA and others prefer to recover divers. Midships the hull is bouncing around less and the situation is more stable. Except, how do you approach the MOB? If you drift down on them, you may steamroll them with the hull. If you come up to them against the wind, as soon as you depower you'll fall off away from them.
Best bet? Come alongside them, either upwind or downwind as conditions merit, and get a line on them. Then USE THE BOOM so you can lift them clear of the water AND CLEAER OF THE HULL and swing them inboard.
If you can't control the boom, leave it trimed in and secure as best you can, you'll still have the advantage of having a multiple part block and tackle to give you LIFT against the MOB's weight.
We rigged a snatch block from a spare 6-part block and tackle, used a bit of light line to make sure it can't tangle while stored. MOB procedure is to clip it on the aft end of the boom and run the line out to the MOB however possible when it is time to recover them.
Using a multi-part block and tackle will make it possible to lift that big wet heavy MOB out of the water and clear of the hull before they get steamrolled by it. The boom? Is no more dangerous than it has been all day every day. Where else are you going to rig a pulley set that gives you lifting advantage and keeps the MOB clear of the hull?
Of course there are other ways to recover someone, and this is not to say a blanket roll in a sail isn't going to be better. That all depends on weather, spare hands, and everything else you need to judge on the spot.