Lights & Shapes

Lights & Shapes: Operational status, maneuverability, and activity markers displayed by ships & vessels

At anchor

Day: One black ball
Night: White light only

NUC - Not Under Command

Day: Two black balls
Night: Two red lights

Aground

By day: three balls in a vertical line
By night: Anchor lights plus two all round red lights.

Trawling

By day: Two triangles pointing at each other
By night: Green over white lights

RAM - Restricted Ability To Manoeuvre

By day: ball/diamond/ball.
By night: All round red/white/red in vertical line plus other lights as appropriate.

Sail (Power)

By day: Black triangle
By night: Port, Starboard Nav light (white light)

Sailing

The tricolour light may be illuminated ONLY when sailing. It must not be combined with any other lights.

Power Driven (>50m)

More than 50m in length shows a Masthead light forward, a second light abaft, and hight than the first, sidelights, and stern light