Apprenticeship: Craft Fundamentals

Capacity is never assumed: the three questions and statics

Before trusting any rigging system, a rigger verifies three separate capacities: the equipment, the components, and the system's operating characteristics. The governing framework is statics: a system in equilibrium has a summation of forces equal to zero, a moment of force is a force's tendency to produce rotation, tensile force pulls a material apart while compressive force pushes it together, and the load on a shackle's pin is shear force. These definitions are the vocabulary every later calculation rests on, so learn them exactly as named.