Close aboard for ships refers to what distance?

• A. 600 Yards
• B. 300 Yards
• C. 1,000 Yards
• D. 50 Yards

Answer: (A)

Close aboard is a ship-handling term that marks a proximity where another vessel is close enough to be seen clearly and to receive direct signals or commands, yet not so tight that immediate collision risk dominates. In this context, 600 yards is the defined distance for close aboard for ships, giving enough range for visual signaling and coordination while still allowing safe maneuvering. A distance of 1,000 yards is farther away than what “close aboard” implies, so it wouldn’t be considered close aboard. Very close distances like 50 yards are typically associated with boarding or alongside operations rather than standard underway signaling. While 300 yards is closer than many ordinary separations, the figure used here for close aboard aligns with the standard convention of 600 yards.