It is the anchor chain.
The swing circle is calculated by determining the distance from the center of the vessel's anchor to the outermost point of the vessel's bow or stern when at anchor. This distance is typically measured by adding the length of the vessel to the length of the anchor rode (the chain or line connecting the anchor to the vessel). The swing circle represents the area in which the vessel may drift while at anchor, helping navigators to avoid collisions with other vessels or obstacles. It’s essential to account for tidal changes and wind effects when assessing the swing circle.
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A bow stopper is a fitting to secure the anchor chain or rode to the vessel's bow when the anchor is raised. A chain stopper is used to hold the anchor chain in place and relieve strain on the windlass when the anchor is deployed or retrieved.
The turning radius of a vessel is a mathematical computation used to determine the turning circle of the vessel during anchoring in order to check if the anchor is dragging. It can be computed by adding the length of the anchor chain to the overall length of the vessel and subtracting the length between bridge and aft.
The cable attached to an anchor is typically referred to as the "anchor line" or "anchor rode." This line can be made of various materials, such as rope or chain, and is used to connect the anchor to the vessel, allowing for secure anchoring in the water. The choice of material and type can depend on factors like the weight of the vessel and the seabed conditions.
An anchor ball is a sphere attached to the vessel of an anchor buoy, used as a signal to state that the vessel is anchored.
An anchor is fastened to a chain and or hawser. It is used to fasten a ship or boat to the sea bed, and so prevent the vessel from drifting. The anchor is only dropped once the way is almost off the vessel - it is not normally used to bring the vessel to a stop.
An anchor light is a lantern shown at night by a vessel at anchor.
The rope (or "line" as we call it in the nautical world) is called the anchor line. However the the chain, shackle,gear & line that are attached between the actual anchor and the vessel is referred to as the "rode".
an anchor that is on a chain and is winched up onto the boat
In a storm a sea anchor can help a vessel from drifting off course. It will keep the bow in the wind and slow the speed of the vessel.
A heavy stone used as an anchor is typically known as a "anchor stone" which is designed to provide weight and stability to keep a boat or other object in place. These stones are often attached to a rope or chain to lower it into the water and secure the vessel.