Girth hitch on a bight - an application specific knot - PICs
First the obligatory caution, disclaimer, and warning:
NEVER AT ANY TIME WAS THIS THE SOLE SUPPORT OF MY WEIGHT. IT WAS EITHER SUPPLEMENTAL TO THE SETTING OR THE TRAVERSE LINE.
IT IS THE RESPONSIBILITY OF THE USER TO INSURE HIS SAFETY. I AM IN NO WAY SUGGESTING OR IMPLYING THIS HITCH/SET-UP AS DESCRIBED HERE AS SAFE FOR ANY APPLICATION AND ESPECIALLY NOT FOR LIFE SUPPORT. THE SETUP DESCRIBED HERE IS EXPERIMENTAL AND ESSENTIALLY UNTESTED. USE AT YOUR OWN DISCRETION.
I know, I know, I don't like it either.
So why would anyone need to tie a girth hitch on a bight. Well, quite honestly, it would probably be a rare need indeed, but I do have one application that it seems to be well suited to.
When Hunabku and I were working on single line traverses (SLT), we quickly discovered there's a loading/release problem. The actual problem is that you are hanging from a rope setting and need to transfer your weight to the traverse line. Let's say you are on a DRT setting and have yourself attached to the traverse line pulley and all you need to do is disconnect from the DRT and 'let fly'. There's the problem: the more you release the DRT, the further down the traverse line you go. Your weight is shared by the DRT setting and the traverse line - there's just no way to quick release and uninstall your DRT setting.
My solution was to use a separate lanyard with a quick release hitch, the Lapp knot to be exact. I used 8mm prusik cord although I'd be just as comfortable with 7mm since it is always doubled and is not used for life support. You would set up the lanyard with the quick release, load it, and then you are free to uninstall the DRT setting. When you're ready to go, you simply pull the release line and off you fly. This solution requires a connection to the harness and a loop knot to implement the quick release Lapp knot. I was using an anchor for the harness attachment and a directional F8 for the release loop and one leg of the lanyard - hmmm, I need a pic of that. It worked well and is certainly a good solution. But then while playing with a biner and some cordage, I came up with this - the girth hitch on a bight:
And from the other side:
Although this is untested in an actual setting, preliminary tests indicate it's going to work fine and it has a certain eloquence of a single knot providing a secure (non-life support) attachment with a loop for the quick release in a pretty 'tight' package.
Here's a close-up of the hitch and a Lapp knot:
and a pic with the loop:
The long leg of the cordage would be place around a suitable anchor and brought back to the loop formed by the girth hitch on a bight and secured to the loop with the Lapp knot. In actual practice, I have had this set up supporting a large portion of my weight but, NEVER AT ANY TIME WAS IT THE SOLE SUPPORT OF MY WEIGHT. IT WAS EITHER SUPPLEMENTAL TO THE SETTING OR THE TRAVERSE LINE.
As always, IT IS THE RESPONSIBILITY OF THE USER TO INSURE HIS SAFETY. I AM IN NO WAY SUGGESTING OR IMPLYING THIS HITCH/SET-UP AS DESCRIBED HERE AS SAFE FOR ANY APPLICATION AND ESPECIALLY NOT FOR LIFE SUPPORT.
Just a word or two about the Lapp knot. I have seen several, if not numerous, quick release hitches over the years, but as far as I'm concerned the Lapp knot is head and shoulders above the rest. When it releases, no part of the cordage slides through a bight or loop, the knot just simply falls apart. In the application I used it, when I pulled the tail the knot releases and I have a full hand(s) grip on the tail and a 2:1 plus friction to hold myself in that position. To complete the release, I simply release the tail and it goes flying around the anchor and can come flying back toward you, so needless to say be ready for that and have eye protection in place. I've never had the end hit me but the potential is there. Hence DO NOT TIE A KNOT IN THE END OF THE TAIL!!! Getting hit by the whipping tail of a cord is one thing, getting hit with a knot in the end of the tail would be even less desireable.