COLREGs · Rule 27
Vessels Not Under Command or Restricted in Their Ability to Maneuver
TL;DR
NUC: two all-round red in a vertical line + two balls by day. RAM: red-white-red vertical + ball-diamond-ball by day. Mineclearing, dredging, divers — each has a distinct light/shape combination.
Why it shows up on the exam
Rule 27 is the rule with the most distinct shape combinations in the entire book.
Authoritative source
- 33 CFR §83.27— verbatim Inland Rule text (US Code of Federal Regulations)
- International COLREGs Rule 27 verbatim text is published by the IMO. The Inland counterpart 33 CFR §83 chunk above mirrors the international wording almost verbatim.
Inland parallel
Inland Rule 27 — Vessels Not Under Command or Restricted in Their Ability to Maneuver →More from Part C — Lights and Shapes
Related drills
- Rule 20 — Application (Lights and Shapes)
- Rule 21 — Definitions (Lights)
- Rule 22 — Visibility of Lights
- Practise Rule 23 — Power-driven Vessel Underway
Drill COLREGs Rule 27
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