Screencast Series: Lesson III
Mechanical Advantages: Part 2- Counting and Estimating System Efficiency

In this UPDATED Screencast, we begin to dabble into the non-linearity of mechanical advantages with Estimating System Efficiency. Although some feel as though this may not be as critical as other topics, hopefully this screencast will change your mind. Regardless of your discipline of vertical movement, one the constant across all domains is the requirement of understanding, estimating, and exploiting friction. Friction is your friend on rappels and lowers, but your enemy when discussing hauls.
We build upon the basic principles covered in the counting tensions screen cast and show how to optimize your MA’s with limited kit, evaluate bail-out kits on hasty hauls, and why using a device made to belay or rappel as your PCD may suck. We also review efficiencies between between various 5:1 systems (simple vs. complex vs. crevasse) and why you need to input efficiency from the start.
We have designed many of these screen casts for a basic internal team / individual sustainment for those who are NFPA 1006 certified, professionally guide, recreationally climb / canyoneer and/or perform mountain rescue. We have broadened the examples and systems outside of traditional MA’s including mountaineering, canyoneering, climbing, and operational mobility context specific applications.