Mechanical Advantage - Jiggers

An Introduction to "Jiggers"

A Jigger System is a mechanical advantage system that uses pulleys to increase the force applied to an object. It is typically used in rescue and rigging operations where multiple people are needed to apply force to an object, such as a stretcher or piece of equipment.

Generally, these beauties are considered pre-rigged pulley systems used mainly for hauling, but can be very important in lowering heavy loads as well. The advantage of these systems is in their rapid deployment, and straightforward operation without advanced levels of training or expertise. They are low maintenance and high yield work horses and have been around for many a year.

Problems & Solutions

Jigger Uses

The usefulness of pulley systems extends well beyond simply the lifting of the rescue package:

Quickly adjusts litter attendant position
High angle litter scoops
Solo pick-off
Easily pass knots
Correct disoriented equipment under load
Effortlessly transfer loads
Promptly establish dynamic fixed brakes
Pretensioned back-ties
Anchors - Redirect or Otherwise
Establish travel restriction
Dynamic lowers
Dynamic directionals
Hauling systems
High angle attendant tether
Load-releasing hitch
Personal mechanical advantage (PMA)
Solo pick-off
Tensioned guying

Jigger Considerations

An optimum advantage of comprehending pulley systems is the fact it frees the rigger to assemble the system specific to the need. The following are key considerations before building a pulley system:

Hauling area — What space is available for the hauling team?
Throw length — What is the throw length? Is it sufficient?
Haulers present (input) — How many haulers are available for the task to be undertaken?
Load to be lifted (output) — The actual mass to be lifted: Climbing, rescue or extreme rescue load. Highline tensioning?
Rope needs — How much rope is available for the pulley system you intend to construct?
Equipment needs — How much equipment is available for the task you intend to undertake?
Hauling area incline — Can you pull downhill? Wouldn’t you rather?
Adaptability — Can you easily change the mechanical advantage?
Resetting — Resetting can use valuable time & energy. Does the pulley system minimize this?
Lowering ability — Can the pulley system lower easily under control? Also, will it respond quickly? River rescue? Live bait?