USCG Exam Practice · Light List, ranges, and light characteristics
When a light is listed in the Light List with no colour designation in its characteristic string — for example, 'Fl 6s' — what colour is the light?
- AThe colour is unspecified and must be confirmed by chart inspection
- BGreen, as green is the default for unlisted buoy lights
- CWhite, because white is the default colour and is omitted from the characteristic string✓ correct
- DRed, because red is omitted when the light marks the port side of a channel
Why C is correct
Per the Light List, white is the default light colour and is omitted from the characteristic string. Therefore 'Fl 6s' with no colour designation indicates a white flashing light with a 6-second period.
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