4.1 Anchoring gear / Ground Tackle
Ground tackle, also known as anchoring gear, is a vital system onboard any merchant vessel. It allows the ship to safely come to a halt in open water or at anchorages.
In this chapter we’ll learn about a ship's anchoring system, legal considerations, and the different anchoring scenarios a merchant vessel might encounter.
Anchoring gear or ground tackle is situated on the forward manoeuvring station (FMS) of a vessel.
The Anchoring System
At the heart of the anchoring system lies the anchor itself, a heavy metal object designed to dig into the seabed and hold the vessel in place. Anchors come in various designs, but the most common type used on merchant ships is the high-holding power (HHP) anchor. These anchors are known for their "fully balanced" design, ensuring they land and embed themselves effectively regardless of orientation.
The anchor is connected to a long length of steel chain, typically ranging from hundreds to over a thousand meters depending on the size of the ship. This chain is housed within the chain locker, a dedicated compartment located in the forepeak (forwardmost part) of the vessel.
To manage the deployment and retrieval of the anchor chain, the vessel uses a windlass. This is a powerful winch equipped with a mooring drum and a gearbox to handle the immense weight and tension involved.
Guiding the Anchor Chain
As the anchor chain travels between the windlass and the anchor, it must be meticulously guided. This is the role of hawsepipes, large diameter steel tubes leading from the chain locker to the hawse holes located at the forecastle (forward upper deck) of the ship. Guide rollers positioned around the hawse holes further assist in the smooth movement of the chain.
Additional Equipment and Considerations
Several other components play a crucial role in anchoring operations. Bollards, which are strong posts located on the deck, serve as secure mooring points for lines and cables. Chain stoppers are powerful brakes that prevent the anchor chain from running out uncontrollably.
Why Anchor?
Merchant vessels utilize anchoring systems for various reasons. During loading or unloading cargo operations, anchoring allows the ship to safely maintain its position at a harbor or designated anchorage.
When navigating narrow channels or areas with restricted visibility, anchoring might be necessary to wait for safer passage conditions. Additionally, anchoring can be used for maintenance or repairs at sea.
Legal Requirements
International maritime regulations mandate that merchant vessels carry anchoring equipment that meets specific strength and design criteria. These regulations are established by the International Maritime Organization (IMO) to ensure the safety of vessels and prevent collisions at anchorages.