Navigation General · Piloting & Bearings
When doubling the angle on the bow, the first relative bearing is 30° and the second is 60°. The vessel ran 4 nm between bearings. What is the distance from the vessel to the lighthouse at the second bearing?
- A8.0 nm
- B2.0 nm
- C4.0 nm✓ Correct
- D6.9 nm
Explanation
When the angle on the bow is doubled, the distance off at the second bearing equals the distance run between bearings. The angle doubled from 30° to 60°, distance run = 4 nm, therefore distance off = 4.0 nm.
Authority: Bowditch (Pub. 9), Ch. 8
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