When a power-driven vessel is towing and the tow exceeds 200 metres, how is the masthead light displayed?

When a power-driven vessel is towing and the tow exceeds 200 metres, the masthead light is displayed in a vertical line on either the foremast or the main mast. This specific configuration is important for ensuring that the vessel is easily recognizable to other ships and can help in determining the vessel's length and the nature of its operation.

Positioning the masthead light in a vertical line serves to indicate that the vessel is engaged in towing, which can affect navigation and safety on the water. The vertical arrangement allows other vessels to identify the towing vessel from a distance, especially in low visibility conditions.

It is essential to adhere to these regulations, as other options would not provide the same level of clarity or might not be compliant with the International Regulations for Preventing Collisions at Sea (COLREGs). For example, displaying the light in the stern or in a horizontal line might not effectively communicate the presence of a long tow, and displaying it in the bow would not follow the requirements set forth by the regulations for vessels engaged in towing.