|| Starpath online classroom || Electronic Navigation Glossary || Glossary Index || Home ||

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 
relative bearing

Bearing relative to heading of a vessel ( labeled "R" ), expressed as the angular difference between the heading, 000º R and measured clockwise through 360°. The starboard beam is 090 R, aft is 180 R, port beam is 270 R, and so forth. In head-up Radar mode, all bearings are measured in relative units.

In head-up mode on radar, all bearings are measured in relative units.

Phrases such as "on the port beam" means a direction of 270R ± 22.5º or so, where the 2 points (22.5º) is a rough uncertainty. "Broad on the port beam" would mean more like exactly 270R.

Similar phrases are "on the starboard bow" meaning 045R ± 2 pts or "broad on the port bow" 315R, and also the quarter, meaning 135R and 225R.

Note that apparent wind angles are also measured relative to the bow, but only 0 to 180 and then labeled port and starboard.

See also aspect.

See also Tricky Terms in Navigation.


[close window]