What is the light characteristic of the Black River "X"?

The light characteristic of the Black River "X" is described as Fl G 4s, which indicates that the light will flash green at regular intervals. The "Fl" stands for flashing light, while the "G" designates the color green. The "4s" signifies that the light will flash once every four seconds, creating a rhythmic pattern that helps navigators identify this specific light marker.

Understanding the light characteristics is essential for safe navigation, as different colors and flash patterns indicate various locations or dangers in waterways. Green lights typically indicate the starboard side of a navigational route. This characteristic helps mariners in positioning their vessels appropriately in relation to this marker.

In this context, other options may represent different light characteristics that do not match what is specified for Black River "X." Knowing the specific characteristics of aids to navigation is crucial for maintaining safety on the water, and recognizing how they differ allows navigators to respond appropriately to their surroundings.