Rule 28 — CBD Vessel Lights
NIGHT. A vessel shows THREE all-round RED lights in a vertical line in addition to the lights required for a power-driven vessel. What is she?
Scenario briefing
NIGHT. A vessel shows THREE all-round RED lights in a vertical line in addition to the lights required for a power-driven vessel. What is she?
Applicable COLREG rule(s)
📸 Night recognition — 8 aspects
The same vessel rendered every 45° of aspect — bow, starboard bow, beam, quarter, stern, port quarter, beam, bow. Use this strip to learn how the lights present from each approach angle. Click any image to view full size.
Key teaching points
- Rule 28: a vessel constrained by her draught may exhibit, in addition to her PDV lights, three all-round RED lights vertically where best seen.
- Day equivalent: a cylinder.
- CBD is qualified priority: vessels that CAN avoid impeding, MUST — but Rule 18(d)(ii) makes the CBD navigate with particular caution.
- CBD is distinct from NUC (red-red), RAM (red-white-red) and fishing (red-over-white) — the count and arrangement is the cue.
Common mistakes to avoid
- Treating three vertical RED lights as a fishing signal — fishing is red-over-white (two lights), not three reds.
- Treating CBD as a stand-on equivalent — Rule 18(d) gives qualified priority only, and the CBD still bears Rule 18(d)(ii) caution.
Why it matters
Exam relevance
Rule 28 CBD lights are a probing distinction from NUC and RAM in STCW OOW orals; Yachtmaster Offshore examiners pair it with Dover Strait/TSS traffic questions.
Related scenarios
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