Basic Collision Regulations Light Recognition All vessels over 7m long carry side lights and stern (overtaking) lights.Motor vessels carry a white masthead (steaming) light shining forward 225°.Motor vessels over 50 m long carry a second masthead (steaming) light aft and above the first masthead light.A motor vessel less than 7m long may carry a single all round white light.A sailing vessel less than 7m long should show side and stern lights if possible, or carry a torch to illuminate the sails when necessary

Stern Light Rule 21(c) Stern Light: The stern light is a white light placed as near as is practicable at the stern. The light shines in an arc of 135 degrees.

Sidelights Rule 21(b) Sidelights: Sidelights are red (port side) and green (starboard side) lights than shine in an arc of 112.5 degrees from straight ahead to a point 22.5 degrees abaft the beam.

Masthead Light Rule 21(a) Masthead Light: The ‘masthead light’ is a white light placed over the fore and aft centerline of the vessel showing with an arc of 225 degrees.