Rope Rescue Mechanical Advantage

Theoretical and actual MA across rig types with pulley losses.

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Formula and source

Theoretical MA per rig type × pulley_efficiency^n_pulleys. Haul force = load / actual_MA. Common rigs 1:1, 2:1, 3:1, 4:1 (Z-rig), 5:1 piggyback, T-method.

NFPA 1006 / NFPA 1670 by name; CMC Rope Rescue Manual + Rigging for Rescue training materials by name.

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