Bearing

A bearing is the horizontal direction from the observer to a distant object, measured clockwise from a reference direction—true north, magnetic north, or compass north—and expressed as a three-figure notation from 000° to 359°. Bowditch (American Practical Navigator) defines bearings precisely by their reference, distinguishing true, magnetic, and compass bearings, each requiring specific corrections to convert between them. On the navigational plot, simultaneous bearings of two or more charted objects intersect to form a position fix. The OOW takes visual bearings using the pelorus or azimuth mirror and radar bearings from the radar display to monitor the vessel's position and to determine the risk of collision with another vessel. Under COLREGs Rule 7, bearing is the primary tool for assessing whether a close-quarters situation is developing: a vessel on a steady bearing and decreasing range presents a collision risk. Regular bearings logged at set intervals also constitute admissible evidence in post-incident investigation, making accurate and timely observation an essential watchkeeping discipline.