Navigation General · Light Ranges
The 'nominal range' of a light listed in the Light List is the range at which it can be seen in:
- AAny weather
- BFog
- CA clear atmosphere defined by a meteorological visibility of 10 nautical miles✓ Correct
- DDaylight
Explanation
Nominal range assumes a standard clear atmosphere (10 NM meteorological visibility). The luminous range (actual conditions) is found from the luminous range diagram, and the geographic range depends on the heights of the light and the observer.
Authority: USCG Light List; luminous range diagram
Practice the full Navigation General bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Navigation General questions
- Light Ranges
The geographic range at which a light may be seen depends primarily on:
- Light Ranges
'Bobbing a light' — deliberately raising and lowering your eye to make a light appear and disappear at the horizon — is used to:
- Dead Reckoning
A vessel departs a known position at 0800 on course 090°T at 12 knots. What is the DR position at 1100?
- Time-Speed-Distance
Using the 60 D = S × T formula, how long will it take a vessel traveling at 15 knots to cover 45 nautical miles?
- Time-Speed-Distance
A vessel travels 90 nautical miles in 6 hours. What is the vessel's speed?
- Dead Reckoning
Which of the following is the best definition of a Dead Reckoning (DR) position?