Other seagoing terms that provide succinct definitions for spatial orientation in a marine environment, or a location on a vessel, that are usefull to understand are as follows:Ībaft (preposition): at or toward the stern of a vessel, or further back from a location, e.g. Some people are able to develop a sailor's eye much better than others but time at sea helps. For example, an object to the East would have an absolute bearing of 90°.

Likewise it can be express as the clock face, with an object appearing directly on the starboard beam being at 3 o'clock.Ībsolute Bearing The absolute bearing refers to the angle between the magnetic north, magnetic bearing, or true north, true bearing, and an object. It can also be given in points, an interval of 111° as in ' two points off the starboard bow. Typically, the relative bearing is given as a horizontal angle measured clockwise from 000° (dead ahead) through 359°.įor example, an object relative bearing of 0° would be dead ahead an object relative bearing 180° would be behind. The relative bearing of an object is the clockwise angle from the heading of the vessel to a straight line drawn from the observation station on the vessel to the object. Relative Bearing The direction of an object from a vessel relative to the vessel's heading. But where more precision is needed there are two other options:

The above sector definitions, augmented by 'port' and 'starboard' as appropriate, e.g fpo provides adequate detail for most recreational sailing. Sector definitions for object areas relative to the vessel's heading If this should continue, the vessels will collide. This is no better exemplified than with a constant bearing, decreasing range (CBDR) bearing, the term used to indicate some object, usually another vessel viewed from the one's own vessel, is getting closer but maintaining the same relative bearing. Moreover, the ability to further use this as a reference to judge the relative motion, that is, to be able to judge the changing distance and bearing between the moving vessel and a stationary object or another vessel is an important ability for all mariners to develop. To be able to communicate the relative position and movement of a vessel or object is vital for safety of navigation. Having a single clear sectorial naming convention for the surrounding sea areas with reference to the various relative points of the vessel delivers this. When navigating a vessel it is important that direction from which objects appear can be efficiently and effectively communicated.

Relative bearing and true bearing