Knot in Lifesling bridle?

[k7cej]

The training syllabus from The Sailing Foundation (the inventors of the Lifesling) as well as their videos show the hoisting tackle being hooking into the loop of line connecting the D-rings. The reason is simple; after pulling the MOB as close up as possible by hand, the D-rings will still be about 1' above the water and out of reach from the deck of most boats. They recommend that the loop be of a size to just reach the rail.

After further thought, I have decided to make a continuous loop out of 1/4" spectra single-braid using a locked brummel and bury. I will then splice the retrieval line around this loop. This way, if one forgets to uncleat the towing line before starting the hoist (as 4 of 5 of our practice class did), one has a couple of feet of hoist before the fouling threatens to bust something.

It's one thing to know in theory how to do something, and entirely something else to actually do it correctly. To all of you out there with unused Lifeslings, I heartily recommend that you actually practice at least hoisting a wet body onto the deck. You may be surprised at how hard it is to get it right the first time.

[Dan Lehman]

Originally Posted by k7cej

The training syllabus from The Sailing Foundation (the inventors of the Lifesling) as well as their videos show the hoisting tackle being hooking into the loop of line connecting the D-rings. The reason is simple; after pulling the MOB as close up as possible by hand, the D-rings will still be about 1' above the water and out of reach from the deck of most boats. They recommend that the loop be of a size to just reach the rail.

And I apologize for only musing that ring-loading should be anticipated -- for
you said that exactly this loading is expected! (And above confirmed that.) And
it is this loading that has rendered the original Bowline into what surprised you.
But that was a Bowline with its tail most unfortunately stitched -- both in terms
of immediate performance and esp. with regard to this advice to size the eye
per rail-height from water level! (The tail should've been stitched to itself,
and thereby the size of the eye could be adjusted per boat (presumably one
won't be hollering "Wait a moment, don't go under yet, I'm adjusting the eye ... !").)

With a well-seized (both where and how strongly done) tail,
the Bowline will work -- it will become a Lapp Bend on ring-loading .
Though, hmmm, it might do some slipping on the hoisting; maybe that was
what motivated the peculiar stitching point -- to arrest this slippage of the
former S.Part, but at the expense of loading the stitching.

I'd prefer Ashley's #1029, which is an Overhand-based eye knot, the
tail brought through the Overhand's "spine" to turn around its "belly" and back
out the spine; this knot has good behavior in any loading. And the tail is
naturally well positioned for seizing (as is the Bowline's if taken to the right
part!). Or make the #1029 base a Dbl.Overhand (Strangle form), for greater
security. Were it laid line, one could just tuck the end a few times vs.
seizing.

Brion, you want a splice? -- for maximum strength? (This is over-rated; security, yeah.)
Have you tested eye splices by ring-loading them?! (I'm wincing at the thought.)

Frankly, I find the suggestion that one should somehow secure the tackle
to the eye baffling -- that eye that is bearing the MOB mass should be closed,
no?! As for hauling up someone unconscious, I'm wondering how that goes,
how the unconscious one manages to be into the device in the first place,
and all.
Or how far this rescue device can be thrown -- is it weighted?
curiouser & curiouser!

After further thought, I have decided to make a continuous loop out of 1/4" spectra single-braid using a locked brummel and bury. I will then splice the retrieval line around this loop.

Remember that this joint might be what needs to move through the D rings,
or which comes into contact with your spliced-to-sling eye (which sounds rather
unkind to the materials). Going out of your way with HMPE for a "stronger"
thinner(?) line might eat away at the strength of the attachment to it (small
diameter rope against rope)!?

To all of you out there with unused Lifeslings, I heartily recommend that you actually practice at least hoisting a wet body onto the deck. You may be surprised at how hard it is to get it right the first time.

I'm more inclined to recommend that the device's serious shortcomings --if they
come with the bowline stitched as was yours, and a regular vs. left-handed Bowline--
be brought to the attention of the USCG and maybe CPSCommision. Consider the
intended use, and : "two came mostly undone during the hoist." !!!

I heard long ago of some supposed Bowline failure for a climber rescue when his
tie-in was used qua sling, ring-loaded ; that struck me as something too far-fetched
for SAR folks to do, but maybe not. Here we see the same knot taken in the same
bone-headed way, with an end stitching that is appalling; and the USCG "approved it"
(money under the table, good ol' boy buddies at the bar doing business, or just some
pretty lax analysis ... ?).

--dl*
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[k7cej]

I am gratified by the scholarly discussion my original post has generated--thanks to all who have contributed. Although I appreciate the various knots that have been advised, I am unlikely to be able to consult Ashley in the middle of a rescue (even though the bible always resides on board).

I have elected to replace the large loop formed by the knot in question with a loop of Spectra/Dyneema of the proper length to reach the rail on my boat when attached to the Lifesling and MOB in the water alongside. I made a loop of 1/4" spectra single-braid with a locked brummel splice, passing the loop through the D-rings on the Lifesling and through a small diameter eye-splice in the polypropylene retrieval line, also made with a locked brummel. I think this is an elegant solution, albeit one customized for the freeboard of my boat.

I did consider the rope on rope chafe on the retrieval line, but remember that this line has a relatively low force on it in use, and even practicing the quickstop and retireval will not get that many uses. The spectra loop is well suited to hoisting the MOB with accompanying higher loads (big man, wet = 300 lbs). And I have absolute confidence in the splices, which are being used in their expected orientations, as opposed to ring-loading a large eye-splice.

Regarding liability, I have written to Chuck Hawley at West Marine, the manufacturer, as well as the president of The Sailing Foundation (who was most helpful in getting us the training materials); he is heading in from a cruise and I expect him to look at this some more in the next few weeks.

[k7cej]

I have been in contact with Chuck Hawley and others at WM as well as The Sailing Foundation, and they agreed that the construction needs improvement. I am convinced they are serious and will continue to work them them. I will let the Spartalk forum know what their final decision is.

FWIW, I have decided that the original knot is a bowline tied as though rotated so one leg of the loop were the standing part. Wierd, huh?

Here is a photo of how I reworked my LIfesling retrieval line:

Here's more detail:

Functional, I think.

[Dan Lehman]

Originally Posted by k7cej

... I am unlikely to be able to consult Ashley in the middle of a rescue (even though the bible always resides on board).
I have elected to replace the large loop formed by the knot in question with a loop of Spectra/Dyneema ...

Oh, really: are you able to do THIS in the middle of a rescue?!

I have been in contact with Chuck Hawley and others at WM as well as The Sailing Foundation, and they agreed that the construction needs improvement. I am convinced they are serious and will continue to work them them. I will let the Spartalk forum know what their final decision is.

Seems it would be best to let them know BEFORE they make a decision,
since you might get better knot advice than is currently available,
as ...

FWIW, I have decided that the original knot is a bowline tied as though rotated so one leg of the loop were the standing part. Wierd, huh?

!???
Yes, wierd that after the knot has been explained above to be the bowline
that you "decided" something contrary. Please re-read what I posted; you should
be able to reconstruct the BOWLINE with tail seized of the original (and, in fact,
you should be able to confirm this via the makers and other Lifeslings, which
have the knot). You are wrong about the knot that you presented here, given
your remarks about which ends go where (S.Part eye leg, Tail eye leg, & S.Part).
Again: the knot was a bowline, with the tail turned back and seized to the S.Part;
the knot was deformed upon ring-loading which apparently is an expected
loading for the structure.
There are KNOTS to remedy this; I suggested one above.

Another comes to mind immediately: the Offset Ring Bend eye knot.
You can see it here: http://docs.google.com/Doc?id=dfxv4svj_0f8xtcfdt&hl=en

Thus, when ring-loaded, you have a pure Ring Bend. QED.
And both this eye knot and the #1029 one orient the tail so that it can
be easily seized to an eye leg, if that's desired; unlike in the present
case where it's seized via an awkward turn to the S.Part, there should
be less load on the seizing in these cases (and the knots are more
stable).

But there might be better knots of a similar tact; e.g., one can make
a suitable bowlinesque knot to do the trick, if untying the knot is a
desired characteristic for the knot (it might not be).

--dl*
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