MOB / COB Procedures for the Short-Handed
Had a good discussion today about MOB / COB procedures for husband and wife crews during a RYA First Aid course. The instructor had participated in recovery tests, and he wasn't positive about the results.
(He wasn't even positive about sugar scoop sterns, noting that they can act like hammers on people in the water. He noted that in some tests the crews moved the person overboard up to the shrouds for the lift-out even if they had a sugar scoop stern.)
First of all, the challenge of a wife recovering an overboard husband is not a simple task. In addition to doing a short stop, figure eight, or similar maneuvers to return to the COB (and dropping sails, etc.), the bigger challenge may be the recovery of the person into the boat before hypothermia makes the person in the water all but comatose.
I've spent about 25 minutes in the water here (around 6 degrees C) in a full wetsuit, and I was amazed by the cold. I was ready to be out after that-- and being in full sailing kit would have been a lot worse. The instructor said that he had "hit the water" in a test fully clothed, and after 20 minutes he was unable to help in his own recovery in any way.
(Side note: in the UK, nearly all the boats I've been on have had the life lines secured at the aft of the boat with many strands of thin line-- not mechanically connected to the pushpit. The line is there so that it can be quickly cut to lower one or both life lines in a COB situation. In the all the videos below, both lifelines are still up.)
So, one way for a recovery is the elevator method:
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This looks fine, but others report that it takes a fully alert and agile crew member to handle it. This means that even in warm water, a less than agile crew member may not be able to pull this off.
A second way is using a vertical life with a life sling:
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Our instructor today was down on this method for two reasons. First, in his testing, it took four yachtmasters around 35 minutes to rig all the blocks on he end of the boom to make this work. (Imagine a spouse doing this alone this while also managing the boat alone in rougher conditions.) Secondly, if a person has been in cold water for some length of time (15 minutes or longer), the vertical lift method can cause a rush of blood downward that can trigger a heart attack. This occurred more than once when helicopters used to do rapid vertical lifts of victims-- some were doa.
Another method involves two strops and a more horizontal lift:
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This looks more comfortable, and safer, but the set up looks complicated and the person in the water may need to be pretty active and focused. As the video notes, more blocks were needed to enable a woman to winch the person aboard.
With all of these conditions, it's not clear that there's an obvious solution. Even launching the liferaft immediately, while the person in the water can still pull himself aboard may not solve the recovery back into the main boat.
Anyway, still thinking about this. Has anyone tried any of the purpose-built recovery sails? Here's an example:
Aladdins Cave Chandlery Ltd Product of the Month February 2007 - Ocean Safety KIM Pick Up Sail
On the plus side, the set up looks more simple. On the down side, a simple halyard winch may or may not be enough for the lift. Also, I wonder if it it would be easy or hard to move the person into it in rougher conditions with only one person on the boat...
The instructor today noted that they had tested this type of recovery by putting a main sail into the water, but it took so long to pull the sail out of the track, etc, that it didn't seem feasible. Water caught in the sail can also affect the person being rescued if they roll face down during the procedure.
So, the mesh of the recovery sail and the faster set up might help, but I wonder if others have tested this.
Jim - great write up and very interesting question. After having seen many videos of Lifesling recoveries - it does not appear to be quick and easy by any means...especially if the person onboard is small. And I'd not heard of the blood rush issue with vertical lifts. Interesting.
The pick up sail is interesting and seems to be a good design. I assume it rolls the MOB as they're coming up - but still...very cool.
After multiple trips into San Francisco Bays chilly waters ... (capsizing a Laser ... dangling from the bow pulpit of the Cal 28 as we docked) .. I can attest that we are searching for a easier method of reboarding ...
presently adding a rope ladder .. to both port and starboard sides .. permanently affixed ..
looking at various mechanical assists ..
thank you for posting .. I will be watching this thread with much interest as we normally sail as a couple .. so far only in relatively calm .. but as the year progresses .. and experience with it .. will want to test our skill .. safely
One major reason to use the recovery sail is to prevent sudden death of the MOB. If an MOB is hypothermic and brought upright suddenly, they may suffer sudden cardiac arrest as the warm blood flows out of their body core.
Yeah - that's in the video Jim embedded. Did you watch it?
A few more notes:
The original primary winches on our boat (from 1973) were not self-tailing, so we upgraded to self-tailing when we replaced them this winter with easier single-person use in mind:
That said, the use of the end of the boom as a lifting point (as shown in the second and third videos above) doesn't make much sense on our boat. The topping lift on our boat is a light line and a light shackle, and I wouldn't trust it to handle the weight of a full size person in sogging clothes. The full main would have to be up, which probably wouldn't be a good idea during the recovery process itself.
The recovery sail appears to use the main halyard (or a headsail halyard) which makes more sense (and we have a self-tailing winch at the base of the mast). However, I wonder if that means clipping the halyard to the recovery sail is all that is needed for leverage, or if an additional six to one tackle system is needed.
On our last boat, we had the life sling with the 3:1 tackle system that was supposed to be raised on the halyard, but others have reported more leverage was needed than this (six to one, eight to one) to make the life comfortable for a single spouse.
Why didn't they just drag the guy up the transom steps?
There are a number of advantages, if the "hammer problem" is manageable.
* No rigging time. Take the line to the winch and crank. There is always a life line gate there. It may be necessary for a crewman with a harness to descend the stair to help, but they don't have to fully lift the person. Padding the steps (one side) with a **** pit cushion helps.
* Can be done with some way on. This is MAJOR. there is no risk of a wave smacking the victim into the boat or of drifting over them. Thus, it is easy to get and keep the victim in the recover area.
* Easier short handed, in my opinion.
* Faster, meaning that in cold water the victim is more likely to be able to help.
* There should be a boarding ladder. Why else have a sugar scoop?
No, it won't work on every boat, but recovery methods can be boat-specific. It seems it should be studied and taught. It's not theory on my part; we've tested this approach a dozen times, both when I have gone over to clear a line or just for drill. The weather was not always nice.
Yes, I've gotten on-and-off dive boats where the ladders move up and down 2-4 feet with swells. Then the over-the-side methods are best, if the MOB is injured or slow.
I LOVE this recovery sail. I'd cheerfully buy or make one over the Lifesling any day. All it needs is an optional reduction block and tackle for the less-upper-bodily-endowed.
The winch would be enough for some people, but for others, a B 'n T would be better.
Consider how much better it would be for an injured MOB vs. being hoisted up by a sling.
For shorthanded sailing, I would highly recommend MOB beacons so you don't leave behind the person who fell in the water.
Some of them will leave a GPS waypoint automatically, which will allow you make a sandwich, have a drink, and take a quick nap before you turn the boat around for all that pesky MOB business.
I took the 103 ASA course this winter and the captain taught the heave to method of getting back to the COB.
This method seemed to work well and was well suited for short handed crew. The hauling back on part however was not discussed.
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