A throwline instrument is a lightweight rope-based tool used in surveying, construction, arboriculture, and utility work to guide or pull a line over heights or obstacles. It typically consists of a thin, strong cord (throwline), a weighted bag or projectile (throw bag), and sometimes a reel for storage. It is designed to help position ropes or cables in hard-to-reach areas.
Operation:
The throwline instrument operates by attaching the throw bag to the end of the throwline and manually or mechanically throwing it over a high point such as a tree branch, pole, or structure. Once the bag passes over the target, the line is pulled through, allowing ropes or cables to be drawn into position. It is commonly used for setting up climbing lines, electrical cables, or survey lines safely and efficiently.
