02/04/2026
โต A Relative Bearing Compass Card (also known as a Relative Bearing Rose, Pointing Card, or Relative Compass Rose) is a fixed navigational reference diagram permanently displayed or engraved on the bridge of most large commercial vessels, including container ships, bulk carriers, and tankers.
โถ๏ธ It is used to indicate the direction of any external object, such as another vessel, navigation light, buoy, radar contact, or hazard, relative to the shipโs current heading (i.e., the direction in which the bow is pointing). This enables immediate, clockwise ship-centric navigation and supports fast decision-making, particularly in collision avoidance situations.
โต A vessel is divided into port (left) and starboard (right), with the shipโs bow always aligned at 0ยฐ (dead ahead) at the top of the card. All bearings are measured clockwise from the bow.
โถ๏ธ The Relative Bearing Compass Card is traditionally marked using the 32-point compass system (where 1 point equals 11.25ยฐ, and a full circle equals 360ยฐ). They're essential for quick and clear verbal communication and situational awareness especially in high-noise or high-pressure environments.
It allows the crew member or Officer of the Watch to report the position of objects instantly without the need to reference or calculate true or magnetic north.
โต 1. Dead Ahead โ 0 Points (000ยฐ Relative)
An object is dead ahead when it lies exactly on the vesselโs fore-and-aft centreline, directly in line with the bow and both sidelights (red and green) are visible at night. On the relative bearing compass card, this is 0 points (000ยฐ relative).
โถ๏ธ What It Means in Practice:
The target, whether another vessel, navigation light, or hazard is positioned directly in front of your vesselโs path of movement. There is no lateral separation, meaning both you and the target are effectively aligned on the same track.
On large vessels such as container ships, the forward view may be partially obstructed by deck cargo, making early detection more difficult and increasing reliance on radar and bridge watchkeeping.
โถ๏ธ Operational Significance:
This is the highest-risk relative bearing because it often indicates a potential head-on situation. Without early action, the risk of collision increases rapidly.
Under the COLREGs, Rule 14 applies when:
* Two power-driven vessels are approaching each other head-on or nearly head-on, and
* There is a risk of collision
Both vessels are required to:
* Alter course to starboard (right)
* Pass port-to-port
* Take early and substantial action
On Restricted Visibility (e.g., Fog):
When visibility is limited, vessels are required to sound one prolonged blast every two minutes
(as per COLREGs Rule 35)
Source: Bona Unanka
