What lights does a vessel aground show?
Her anchor light(s) plus two all-round red lights in a vertical line. By day: three black balls (Rule 30(d)).
Two reds alone means not under command. Two reds with white anchor lights means aground: keep well clear, there's shallow water there.
- Under 12 m: no aground signals required.
- In fog: the anchor bell, with three separate strokes on the bell before and after the rapid ringing.
Source: COLREGS Rule 30(d), (f) and Rule 35(h).
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Rule 21Question 1 of 5
What is the arc of visibility of a masthead (steaming) light?
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