Navigation General · Buoyage Numbering
In the U.S. lateral system, odd numbers are assigned to which marks, and where do the numbers generally increase?
- ARed marks, increasing toward seaward
- BSafe water marks, unnumbered
- CYellow marks, decreasing inbound
- DGreen marks, increasing as you return from seaward (proceeding upstream/toward the head of navigation)✓ Correct
Explanation
Green aids carry odd numbers and red aids even numbers; numbering increases proceeding from seaward toward the head of navigation. Combined with 'red right returning,' this lets a mariner gauge progress and which side to favor.
Authority: USCG Aids to Navigation; IALA Region B
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