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65%
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53
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Bowditch Ch. 5 §503
Bowditch Ch. 5 §503 — Short Range Aids to Navigation A light is described by its characteristic, colour, period, height, and nominal range — for example "Fl R 4s" is a red light flashing once every four seconds. Common characteristics are fixed (F), flashing (Fl), occulting (Oc), isophase (Iso), and quick (Q). The Light List gives the authoritative character, range, height, and structure of every aid, and is the reference for identifying a light by its characteristics at night.
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What distinguishes an Isophase (Iso) light from both a Flashing (Fl) and an Occulting (Oc) light?
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