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USCG Exam Practice · Light List, ranges, and light characteristics

A light charted as 'Fl R 4s' produces what characteristic?

  1. AA single red flash every 4 seconds, with the duration of light shorter than the duration of darkness✓ correct
  2. BA continuous red light interrupted by a short eclipse every 4 seconds
  3. CEqual periods of red light and darkness totaling 4 seconds
  4. DA fixed red light with a brighter flash superimposed every 4 seconds

Why A is correct

A flashing (Fl) light produces a single flash regularly repeated with the duration of light shorter than the duration of darkness. The characteristic string 'Fl R 4s' denotes a red flash every 4 seconds. Light List — light-characteristic (Fl).

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A light charted as 'Fl R 4s' produces what characteristic? — USCG Exam Practice · CaptainsGround