Anchor Ball

A black spherical day shape hoisted on a vessel to signal that it is anchored during daylight hours.

An anchor ball is a crucial piece of maritime signalling equipment used to indicate that a vessel is anchored. It is a black, spherical object, typically made of durable material, and is hoisted in a prominent position, usually on the forward part of the vessel, where it can be easily seen by other mariners. The use of an anchor ball is mandated by the International Regulations for Preventing Collisions at Sea (COLREGs), specifically Rule 30, which outlines the requirements for vessels at anchor. The anchor ball must be displayed during daylight hours when the vessel is at anchor in a location where other vessels may be navigating, such as a harbour, anchorage, or near shipping lanes.

The purpose of the anchor ball is to provide a clear visual signal to other vessels that the ship is stationary and not under command, allowing them to take appropriate action to avoid a collision. This is especially important in busy or congested waterways where the risk of collision is higher. The anchor ball is only required during daylight hours, as at night, vessels at anchor are required to display specific anchor lights instead. The use of an anchor ball is a simple yet effective way of enhancing safety at sea, ensuring that all vessels are aware of each other’s status and can navigate accordingly.