As I wrote in my “about” page, I used to be a bit of an adrenaline junkie in my youth. One of my pastimes was rock climbing and rappelling. I’ve top roped, lead climbs, slack jumped, Australian rappelled, body rappelled, prusik ascended standing lines…the works. I no longer have the time, friends available or carefree lifestyle to do much of that anymore. I have sold off most of my climbing gear, leaving only enough to rappel if necessary or do a top rope climb. However, I do still enjoy reading and writing about the technical aspects of ropecraft, so every once and a while I will submit a tidbit of ropecraft knowledge.
Tensionless Anchors: Rigging in this fashion uses rope friction around an object to secure the load. This is one of the strongest riggings. It uses almost 100% of the ropes srtength.
As a knot or any tight bend in the rope reduces it’s load bearing strength by a known percentage, the tensionless anchor avoids strength loss by wrapping the line around an anchor such as this tree. In theory, enough wraps would hold the rope in place without being permanently tied to the object…that of course would be stupid, so the rope is tied off to an object to prevent unwrapping.