Which color is the port side sidelight?

Which color is the port side sidelight?

• A. Red
• B. Green
• C. White
• D. Blue

Answer: (A)

The key idea here is how navigation lights identify the sides of a vessel. In standard COLREGs signaling, the port side (left) uses a red sidelight to mark that side, while the starboard side (right) uses a green sidelight. This color pairing lets other vessels quickly determine which side you’re on and how you’re moving relative to them. White lights are used for stern or other all-around signals, not as sidelight colors, and blue isn’t a sidelight color in the basic navigation light system. So the port side sidelight is red.

The key idea here is how navigation lights identify the sides of a vessel. In standard COLREGs signaling, the port side (left) uses a red sidelight to mark that side, while the starboard side (right) uses a green sidelight. This color pairing lets other vessels quickly determine which side you’re on and how you’re moving relative to them. White lights are used for stern or other all-around signals, not as sidelight colors, and blue isn’t a sidelight color in the basic navigation light system. So the port side sidelight is red.