Chart Navigation & Plotting · Distance — Distance to the Horizon
With a height of eye of 49 feet, your visible horizon (distance ≈ 1.17 × √height) is:
- A8.19 NM✓ Correct
- B4.10 NM
- C57.3 NM
- D1.17 NM
Explanation
Distance to horizon ≈ 1.17 × √49 = 1.17 × 7 = 8.19 NM.
Authority: Bowditch (Pub. No. 9), Distance of the Horizon
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