Sunday Skill builders: Mechanical Advantage

When a partner is hanging in a crevasse, stuck below a crux, or too heavy to simply lower, you need to move a load you can't move by hand - that's mechanical advantage (MA). In this hands-on session we'll demystify hauling systems by building them with our own hands, starting from the two building blocks every system is made of (2:1 and 3:1) and working up to the compound systems used in real rescues. You'll learn not just how to rig them, but why they work, where all the friction goes, and how to pick the least complicated system that gets the job done. We'll build and pull on each system on the floor and the wall so the rigging sticks. This is ground school - master the systems indoors, then apply them on snow and rock. It's geared toward climbers and rescue-minded folks who are comfortable with anchors and friction hitches and want to add raising and hauling to their toolkit.

What you'll learn (topics flex to the group):

• What MA really means: theoretical vs. real-world advantage, and why a "3:1" with carabiners can pull more like a 2:1
• The two foundations - the 2:1 and the 3:1 (Z-drag) - and how every bigger system is just a combination of them
• Simple vs. compound vs. complex systems (and how to tell them apart)
• Progress capture: holding what you've gained with a prusik, autoblock, or ratcheting pulley
• Fixed vs. movable (traveling) pulleys - a pulley on the anchor only redirects; a pulley on the load creates advantage
• Building up step by step: 1:1, a redirected 1:1, 2:1, the 3:1 Z-drag, and a 6:1 compound
• Where efficiency goes: friction, rope stretch, pulleys vs. carabiners, and how a redirect multiplies the load on your anchor
• Gear that matters: pulley types, oval carabiners, and when a carabiner is "good enough"
• Choosing wisely: using the minimum MA the job needs, and why you usually need a 6:1 to raise a non-assisting adult
• Real applications: crevasse rescue, hauling a follower past a hard move, and big-wall bag hauling