Lights on Other Vessels
Click on the diagram on the left; it gives you some typical lights that are displayed by different vessels at night.
It is important to realise that most 'special lights' are shown in addition to the normal running lights of a power driven vessel when a vessel is under mechanical power. For example, the vessel constrained by her draft shows three all round red lights in addition to the normal masthead light(s), sidelights and sternlight.
Note also that a vessel aground (where she has run into the seabed and is fast there) shows two red lights in addition to her anchor lights.
A sailing vessel that is moving shows the same sidelights and sternlight as a powerboat, but does not show a masthead light. A vessel with sails up, but also being propelled by machinery must show the power-driven vessel 'running lights'
A fishing vessel is defined as one engaged in fishing with nets, lines, trawls, or other gear that restricts her ability to manoeuvre. The diagram shows a trawler.
A tug towing a barge is not normally considered to be restricted in her ability to manoeuvre. A tug towing another vessel does not show normal masthead lights, but must show two masthead lights instead one vertically above the other. (normal masthead lights are horizontally displaced, but not in the case of a tug). If the length of the tow is more than 200 meters, it must display three masthead lights vertically disposed. In addition, it displays sidelights and a sternlight. It also must display an all round towing light at the stern, above the sternlight.
A vessel being towed does not display masthead lights, but sidelights and a sternlight.
A towing vessel seen from far away can be confusing to a first time mariner, and care must be exercised.