is this bowline variant a thing?

[Bob Mehew]

I have just caught up with this thread.  The link provided by Keiran.A requires one to download the whole book (for free).  The relevant diagram is on page 35 from the book titled Cave Rescue Techniques 2017 by G Antonini et al, translated by F Cuneo and A Sbisa. 

I use the Ashley Book of Knots to provide a reference and with over 20 entries for bowlines, it is going to take some time to check this variant against them.  It was obvious from scanning the pages of the book as I looked for the image, that the translation whilst good is not using standard terms such as end / bight / standing part as used in ABOK.  So care is needed in reading.  The first point is this book shows its bowline on a bight as a mid rope knot where as the usual bowline on the bight is tied at the end of a rope.  I have not (yet) read further into the book to see what situations they wish to use this knot for.  But the first thought is what are the advantages of this knot over say an Alpine Butterfly knot?

The book states under the title "Information" for this knot that:
      Extremely strong and easy to recognize.
      It shows a good residual load.
      Good for attaching service ropes without using carabiners.
I am struggling to understand these statements.  Could some one read more of the book to get into the style of English as well as see if they cite specific examples?  I am afraid I am rather busy with other matters (theoretical rope testing and radon) so I am not immediately available to read the book.

I also attach a slightly less fuzy copy of the image which shows its manner of tying and I think clarifies the bit about the stopper if one looks at what has been 'crabed in'.

 

[Ian Ball]

It is amusing how the connection without carabiners shows it can be connected to a carabiner.

I've downloaded the book but I won't be reading it quick enough I'm sure.

If I abseiled down a pitch and there was a shared anchor rebelay, I would often use a BotB.  I'm not sure that the end of the rope is needed?

 

[andrewmcleod]

But the first thought is what are the advantages of this knot over say an Alpine Butterfly knot?

Potentially slightly easier to untie than the Alpine Butterfly if the butterfly has been loaded heavily on the loop. Maybe.

 

[andrewmcleod]

I think the only reason to use for a single-bolt rebelay (or a traverse bolt) is if you want to save the carabiner on a smooth resin bolt (then you can connect directly). To be fair, it might be quite nice to do a Yorkshire pothole and only bring half the krabs... (although you probably need slightly more rope).

Another use might be if you had multiple things hanging one rope e.g. the top and tail end of a stretcher, or a stretcher and a barrow boy, or whatever, although why in that situation you would you find yourself short of a single screwgate carabiner I don't know...
Instead of having a Y-hang at the end of the rope, and clipping each thing in with a sling or whatever, you just have a mid-rope knot and then the tail of the rope goes directly to the stretcher strops/tail end horizontal hauling system/whatever, which saves you 6ft of extra rope and a carabiner.  A mid-rope in that situation needs to have the tail come out the bottom of the knot, restricting you to this knot, the Alpine butterfly, the directional Fig 8 and other similar knots (not standard Y-hangs knots). The directional Fig-8 might be a bugger to untie (it does seem to lock down very tightly like a Fig 8), and the alpine butterfly would be in its less-ideal orientation when the loop is loaded. But it would have the advantage that everyone knows what it is...

 

[Keiran.A]

Not that most of our anchors are possible to easily thread a bight through...

i'd think that most anchors i've come across where i'd be willing to tie directly into would take a bight of 10mm.k x

 

[Bob Mehew]

Forgive me for being thick but I don't see how one can tie this Italian variation of a  'bowline on a bight' directly into an anchor?  Has some one done it?  I think you must have to use a crab to clip it into an anchor.

 

[mikem]

I did post about that half way down previous page - basically thread bight through anchor & tie bowline, then rather than clipping bight in you tie a stopper knot with it (Kieran, you can get rope through, but circumference of bight means you really have to force it).

 

[Bob Mehew]

Ah yes.  Thank you.  :-[