Rope Rescue Mechanical Advantage Systems

A raising system using a combination of pulleys to leverage the force applied in lifting is referred to as a mechanical advantage m a system.

Rope rescue mechanical advantage systems.

Understanding how mechanical advantage is calculated will help you create the perfect pulley configuration for any rescue mission you re up against. The first number represents the force on the load and the second number is the force that the rescuers are pulling on the rope. 3 1 system the 3 1 is the classic mechanical advantage system used by rescuers. It requires less rope than a non piggybacked 2 1 system is reasonably easy to rig is easy to add a progress capture device provides an appropriate amount of mechanical advantage to raise one or two people and with a few tweaks it can be converted into a simple 5 1 system.

Raising systems are essential in any rescue or rigging scenario in which loads are lifted using rope. Even if you only need to raise a load 20 feet using a 5 1 you will have to pull a whopping 100 feet of rope and probably reset the system many times. A system s mechanical advantage is expressed as a ratio using a colon. For example a 2 1 or 3 1 system these are pronounced as a 2 to 1 and 3 to 1.