Mechanical Advantage Systems Rope Rescue
3 1 system the 3 1 is the classic mechanical advantage system used by rescuers.
Mechanical advantage systems rope rescue. 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. Four to one systems are less popular than 3 1 systems probably because they require an additional pulley and don t offer significantly more mechanical advantage. Notice however that the end of the rope on 2 1 systems is attached to the anchor whereas the end of the rope on 3 1 systems is attached to the load. The downside of systems with a 5 1 or higher mechanical advantage is you have to pull a lot of rope to move the load a short distance.
Components of a mechanical advantage system. However once you learn how to stack a 2 1 on a 2 1 to create a compound 4 1 you ll know how to stack a 2 1 on a 3 1 to create a 6 1 also a less popular system but worth knowing if you are a rigging geek and how to. In a 3 1 mechanical advantage system mas a 300 lb load would feel like 100 lbs and 3 feet of rope will move the load up 1 foot. For example a 2 1 or 3 1 system these are pronounced as a 2 to 1 and 3 to 1.
Raising systems are essential in any rescue or rigging scenario in which loads are lifted using rope. Whether the end of the rope connects to the anchor or to the load is a subtle difference between mechanical advantage systems that have an even number e g 2 1 4 1 6 1 etc and systems that. A system s mechanical advantage is expressed as a ratio using a colon. Understanding how mechanical advantage is calculated will help you create the perfect pulley configuration for any rescue mission you re up against.