Chart Navigation & Plotting · Piloting — Geographic Range
A light is charted at 64 feet and your height of eye is 25 feet. The geographic range (1.17(√H + √h)) is:
- A10.53 NM
- B15.21 NM✓ Correct
- C9.36 NM
- D20.0 NM
Explanation
Geographic range = 1.17(√64 + √25) = 1.17(8 + 5) = 1.17 × 13 = 15.21 NM.
Authority: Bowditch (Pub. No. 9), Visibility of Lights
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