During an UNREP, what are blocks primarily used for?

Blocks are primarily used in an underway replenishment (UNREP) operation as fair leads for fiber lines. In this context, blocks help guide the fiber lines smoothly during the hoisting and lowering of supplies between vessels. They assist in changing the direction of the line, minimizing friction and wear while ensuring that the lines are properly threaded and aligned. This is particularly important during UNREP, where precise handling and efficient transfer of cargo are essential for safety and success.

While other functions such as weight distribution, securing cargo, and adjusting tension play important roles in the overall operation, the primary purpose of blocks in this scenario is to serve as fair leads, facilitating the effective and safe maneuvering of lines used during the replenishment.