Hauling systems: “the Rule of 12”
More AI image fakery, intended to deceive the public, steal from artists, and probably take over the world at some point. Pardon the slightly lame image, that's the best prompt I could come up with. =^)
I recently watched a whitewater rescue video which emphasized "the Rule of 12": never use more than 12 times the strength of one person in a hauling system.
This was a new concept for me. I thought it was interesting, and I want to share with you.
If you exceed the “Rule of 12”, you're getting dangerously close to the breaking point of some components in the system, such as pulleys, prusik hitches, D rings on boats, maybe carabiners, etc.
How does this apply for actual mechanical advantage systems?
1:1 system: don't have more than 12 people pulling at once
2:1 system: don't have more than 6 people pulling at once
3:1 system: don't have more than 4 people pulling at once
6:1 system: don't have more than 2 people pulling at once
9:1 system, don't have more than 1 person pulling
(Yes, some of these examples are not too applicable for most climbing scenarios, like 12 people pulling on a rope at one time, but you get the general idea.)
In the real world, friction decreases the mechanical advantage of any system. In this case, when you want to avoid breaking gear and you may have a lot of pulling power available, that's probably a good thing.
If you're curious, here’s the video.