Above the vast sea, ships need to use Lights to ensure the safety of navigation. Ship Navigation Signal Lights are to facilitate the discovery of the ship by other ships and to indicate the ship’s navigation dynamics. Therefore, the ship signal light is very important to the safety of the ship’s navigation.
Classification of Navigation Lights
● A Masthead Light at the front; (White)
● The second Masthead Light at the rear is behind and higher than the front Masthead Light (the vertical height difference is at least 4.5 meters; ships less than 50 meters in length are not required to display this Masthead Light); (White)
● Two Sidelights; (Starboard Light Red and Port Light Green)
● A Stern light. (White)
Display Mode of Navigation Signal Lights
● Masthead Light: A light placed above the mast of the ship or above the centerline of the fore and aft, displaying uninterrupted light in a horizontal arc of 225 degrees, and the device should make the light from the front of the ship to the front of each side. Display within 22.5 degrees behind.
● Sidelights: The red light on the port side and the green light on the starboard side, which are placed on the left and right sides of the highest deck of the ship, display uninterrupted lights in a horizontal arc of 112.5 degrees from the bow to the stern. The device should make the lights be displayed separately from the front of the ship to within 22.5 degrees behind the abdomen of each side.
● Stern Light: a white light located in the middle of the stern. Uninterrupted lights are displayed in a 135-degree horizontal arc, and the device is to display lights from directly behind the ship to within 67.5 degrees of each side. The height of the masthead light should be as level as possible with the sidelight, but not higher than the sidelight.
Use of lights in other situations
● When anchoring: only the anchor light (a white All-round light) is displayed.
● Ships out of control: In addition to sidelights and taillights (turned off when not moving against the water), two vertical all-round red lights are to be displayed at the most visible place.
● Ships limited to draught: In addition to sidelights, stern lights, and masthead lights, three vertical all-round lights must be displayed at the most visible place.
● Stranded ship: Two vertical red lights are illuminated.
In addition to these common situations, there are sailing ships, ships engaged in towing, ships with limited maneuverability, and ships engaged in fishing… all have corresponding signal light display methods.