Two Tensioned Rope System over Dedicated Main Dedicated Belay
This is a topic that has received a considerable amount of attention. The idea is that two main lines are used in place of a Main and Belay line. In order for the system to be Dual Capability both lines need to be G rated for rescue.
This post will look at a couple of key points from a Large Animal Rescue perspective.
The advantages of DC TTRS:
- No Shock Load: With a Large Animal Rescue the Shock Load can become catastrophic quickly if a Main Line failure occurs with a traditional Belay.
- Safety Ratio: The Safety Ratio is not as critical since there is no drop in the system from a line failure. It is impossible to even get a 10:1 safety ratio with a Large Animal Rescue, so this system provides a solution to that problem.
- AHD: The Standard is to run both lines through the Artificial High Directional. This eliminates falls at the edge from a line failure. The use of an adjustable second line is also very popular and allows the second line to be adjusted as needed for safety. This adjustable line is beneficial to a Large Animal Rescue since there is often a need to drag the Animal under the AHD after the initial rescue for a direct lift. Being able to adjust a second line to ground level makes a flat drag under the ADH possible.
- Number of Personnel on a Haul Line: Large Animal Rescue can require additional personnel on a Haul Line. TTRS allows more personnel to be used in a shorter distance since they are divided between the two lines.
By Ken Gilden
The following video provides information on human rescue using TTRS but the information is transferable to Large Animal Rescue:
The following article provides a detailed discussion on this topic.