Dynamic rope
A dynamic rope is a specially constructed, somewhat elastic rope used primarily in rock climbing, ice climbing, and mountaineering. This 'stretch' is what makes it 'dynamic', in contrast to a static rope that has very low elongation under load. Greater stretch allows a dynamic rope to absorb the energy of a sudden load such as from a fall more slowly, reducing the peak force and therefore the chance of catastrophic failure. Kernmantle ropes are the most common type of dynamic rope, and nylon has replaced all natural materials such as hemp since 1945 for durability and strength.
Rope Types
Dynamic climbing ropes are classified into three categories: Single ropes, twin ropes, and half ropes (also referred to as 'double ropes').
Single Ropes are designed to be used alone, and are by far the most common, and used for top-roping, sport climbing, and trad climbing.
Twin and half ropes are used for lead climbing, and are designed to be used as a pair - they are not strong enough to be safely used on just a single strand, and they are tested to different standards as a single rope.
- Twin ropes are used by treating the pair of ropes as a single rope, clipping both ropes through the same carabiner at each piece of protection.
- Half ropes are also used as a pair, but only one rope is clipped through each piece of protection- the climber alternates which rope is clipped through each piece. On wandering routes where protection is placed far apart on either side, half ropes can significantly reduce rope drag.
