Question 174Navigation General

70% to pass

Under the IALA-A Buoyage System, when entering from seaward a lateral system buoy to be left to starboard may display which topmark shown in illustration D046NG below?

Diagram for USCG Navigation General: Under the IALA-A Buoyage System, when entering from seaward a lateral system...
A A
B B
C C
D D
AI Explanation

The correct answer is C. Under the IALA-A Buoyage System, when entering from seaward, a lateral system buoy to be left to starboard may display a conical (can) topmark, which is shown in illustration D046NG option C. This is because the conical topmark indicates a port-hand mark, which should be kept to the vessel's port (left) side when entering from the sea. The other options are incorrect because A and B show topmarks that do not correspond to the port-hand marking, and D shows a topmark that is not used in the IALA-A Buoyage System.

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