Been busy practicing how to teach the "Drop-C" and "Z-Drag" methods for crevasse rescue demonstrated on grass with a barrier wall as the crevasse. There is an abundance of methods for retrieving a climber from a crevasse, but the "Drop-C" is superior. This can be done with the same rope or with a second rope. Demonstrating how to shift ones, and the victim's, weight from their belay loop to the first snow anchor is something I want to demonstrate correctly. I intend to display a method which shows how to do the "Drop-C" using just pulleys and prusik cords. Commonly used devices like the Rope Man and the Microtraxion can cause de-sheathing of the rope at 4Kn, whereas a prusik will just slide and than grab again once the forces have subsided. Here are some images of a "Drop-C" using the methods I admit work, but are less safe than the pulley plus prusik (PPP). So when you see these mechanical devices in the diagrams, just know that I'm advocating for an old fashioned PPP! It's safer for everyone on the glacier/mountain! Also, where they show pulling through carabiners, this must be avoided or mechanical advantage is hugely lost. Pulleys, pulleys, pulleys! Each team member during glacial travel must have at least two pulleys and they must be placed as close to the pull strand as possible in a pulley system.
I know this has nothing to do with arboriculture, but that's what I did today.