At night, a power-driven vessel less than 12 meters in length may, instead of the normal navigation lights, show sidelights and All around white light.

At night, a power-driven vessel less than 12 meters in length may, instead of the normal navigation lights, show sidelights and All around white light.

• A. Forward masthead lights
• B. Sidelights and All around white light
• C. Sidelights only
• D. All-around green light

Answer: (B)

The essential idea is that very small power-driven vessels have a simplified lighting option at night. For vessels under 12 meters, you may substitute the normal masthead and stern lights with sidelights (the red and green lights) plus a white light that is visible all around. The red/green sidelights show which side is which, while the all-around white light signals that the vessel is underway and keeps it visible to other vessels from any direction. This arrangement satisfies the required signaling without the full set of lights used on larger vessels. The other options either would not clearly indicate that the vessel is underway, or rely on a masthead or other color that isn’t permitted as the substitute for a small vessel.

The essential idea is that very small power-driven vessels have a simplified lighting option at night. For vessels under 12 meters, you may substitute the normal masthead and stern lights with sidelights (the red and green lights) plus a white light that is visible all around. The red/green sidelights show which side is which, while the all-around white light signals that the vessel is underway and keeps it visible to other vessels from any direction. This arrangement satisfies the required signaling without the full set of lights used on larger vessels. The other options either would not clearly indicate that the vessel is underway, or rely on a masthead or other color that isn’t permitted as the substitute for a small vessel.