This weekend I got myself into (for me) a hairy situation while rappelling. I got to a set of rap anchors that I needed to transfer to in order to get down to the next ledge, so I transferred myself to a quad anchor, took myself completely off rappel, and ran the rope through the rap rings at this anchor (retying my disaster knots of course).
These anchors sit at the top of a massive roof, so at this point the quad was completely loaded, and I was unable to effectively support my weight on the rock and clean at the same time. I set my rappel back up (guide ATC on a chain reactor, maybe 1 or 2 loops away from my harness), tied my prusik (below the ATC), and tested that the prusik would hold.
I'd never been in a situation where it's not possible to completely unweigh your anchor, so I made a rash decision to girth hitch a double length sling on my prusik, and tie a simple ladder into it.
My thought process was this:
- I need to move my weight from the quad onto the rope in order to clean the quad
- The prusik is a friction hitch that by design is meant to hold your entire body weight
- By girth hitching directly to the prusik, I'm loading it and forcing it to grab the rope
- I can then support my weight entirely on the rope and clean the anchor
It was only after I got back on the ground and my adrenaline was settling down that I realized I could have committed a grave error and unnecessarily loaded my one backup, which, if it had failed while I cleaned, would have led to my death.
I then came to the conclusion it would have been much smarter to simply tie the sling directly to the rope in a friction hitch, which may have failed but would not have affected my actual lifeline, the prusik.
Was I in any danger here? Or was I using the prusik as designed?