What type of light must a power-driven vessel have that shines forward and to both sides?

A power-driven vessel is required to have a masthead light that shines forward and to both sides. This light is crucial for the visibility and identification of the vessel to others, especially in conditions of low visibility, such as at night or in fog. The masthead light typically has a white color and is positioned higher on the vessel, ensuring that it can be seen from a distance by other vessels approaching from various angles.

The masthead light in this context serves to indicate not only the presence of the power-driven vessel but also its direction of movement. It is designed specifically for power-driven vessels, distinguishing them from other types of vessels that may have different lighting requirements. This helps in maritime navigation, allowing other vessels to understand the position and heading of the power-driven vessel, which is essential for safe navigation and collision avoidance.

Other lighting options, such as sidelights or a sternlight, have specific functions and placements that do not meet the requirement of shining forward and to both sides simultaneously. The sidelights are used on the port and starboard sides of the vessel, and the sternlight is solely for indicating the vessel's rear. An all-around white light does not specifically indicate the same directional signaling that is required from the masthead light.