Navigation General · Light Characteristics
A light with the notation 'Oc(2+1) 12s' would best be described as:
- AThree eclipses per group — two short, one long — in a 12-second period
- BA composite group occulting light with two eclipses followed by one eclipse, period 12 seconds✓ Correct
- CQuick flashing 2 plus 1 pattern every 12 seconds
- DAn alternating red-white-red occulting light
Explanation
Oc(2+1) is a composite group occulting light: the first group contains 2 eclipses, the second group contains 1 eclipse, and the total cycle is 12 seconds.
Authority: 33 CFR 62 (U.S. ATON System)
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