Determining a position
A bearing can be taken relative to a charted or mapped object at a specific time. This bearing can be used to determine the position of the vessel or landmark when used in conjunction additional bearing(s) or other information (e.g. depth, declination, etc.).
However, a pre-calculated bearing to a charted object can be also be used as a precautionary measure. For instance, if anchored in a harbor with a shore to the north, it can be decided that the vessel must stay to the south of an object to its east. If it does not, an anchor watch must inform someone to take action. Or, if moving through a channel with obstructions to the west and which is not well-marked with buoys, it can be decided that the vessel might have to stay to east of a particular charted object. Similarly, a land navigator might walk a bearing several degrees to the east of his actual course to avoid difficult ground, or to intercept an intersecting position (such as a road or trail) leading to his/her destination.[8] Upon reaching the road, the navigator simply turns west to ensure he will reach the destination.
Piloting
A bearing can be taken on another vessel to aid piloting. If the two vessels are travelling toward each other and the relative bearing remains the same over time, there is likelihood of collision and action needs to be taken by one or both vessels to prevent this.
Warfare
A bearing can be taken to a fixed or moving object in order to target it with gunfire or missiles.
Search and rescue
A bearing can be taken to a person or vessel in distress in order to go to their aid or, when that is not possible, to report the person or vessel to authorities or someone who can go to their aid.
GEOMETRY
15 years ago
