Chart Navigation & Plotting · Aids to Navigation
A buoy showing horizontal red and green bands with the topmost band green marks a:
- ASafe water area on all sides
- BSpecial area such as an anchorage
- CIsolated danger you may pass on either side
- DPreferred channel, with the best water to starboard (keep the buoy to port)✓ Correct
Explanation
A preferred-channel (junction) buoy is banded red and green; the color of the top band shows the preferred channel. Top band green means treat it as a green aid for the preferred route — keep it to port returning, with the better water to starboard.
Authority: USCG Light List; 33 CFR 62
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