If visibility permits, at what range will...

🔍 Key Concepts

• Geographic range of visibility of a light based on its height above sea level • Using the distance to the horizon formula for an observer at sea level • Finding the light’s charted height on the nautical chart or in the Light List, then converting that height into a range in nautical miles

💭 Think About

• How do you convert the height of an object in feet into the distance at which it appears over the horizon in nautical miles? • If your eye is assumed to be at sea level for this question, which part of the distance-to-horizon formula applies? • Once you find the geographic range from the light’s height alone, which option is numerically closest to that range?

✅ Before You Answer

• Verify the height of Orient Point Light from the chart or Light List before calculating • Use the correct distance-to-horizon formula: distance (NM) ≈ 1.17 × √height (feet) for an object when the observer is at sea level • Check that your computed range is reasonable for that height (not too short or excessively long) before picking the closest multiple-choice answer

If visibility permits, at what range will Orient Point Light break the horizon?

9.3 miles

10.8 miles

13.9 miles

17.0 miles