Gob Rope and Gog Systems
The gob rope as a system: rigging, the towing point it restrains, inspection and management, and what the investigations found about its limits.
A gob rope, also written gog rope, leads the towline down and aft to a point on the tug’s centreline so that the line cannot lead far off the beam. By restraining the lead angle it limits the transverse moment the towline can apply, which is the moment that girts a tug.
The joint British Tugowners Association, UK Maritime Pilots Association and Workboat Association advice of November 2025 is explicit that a gog rope must be treated as a gog system rather than as a rope, using a dedicated line managed like a towing rope. It is not a guarantee. MAIB report 17/2024 found that the gob rope on the tug Biter did not prevent the tug being towed sideways and that the assisted vessel’s excess speed almost certainly caused the rope to render, and that the HMPE gob line melted and fused where it was wrapped around the samson post. On the tug Domingue, lost off Tulear on 20 September 2016, there was no gog rope at all.
The full article will cover rigging geometry, towing point management, material choice between steel wire and synthetic rope, render behaviour under load, inspection and retirement, and the 2025 industry advice in full.