Chart Navigation & Plotting · Tides — Under-Keel Clearance
Your vessel draws 18 feet. The charted depth is 16 feet and the height of tide is +5 feet. What is the under-keel clearance?
- A3 feet✓ Correct
- B2 feet
- C5 feet
- D21 feet
Explanation
Depth of water = 16 ft charted + 5 ft tide = 21 ft. Under-keel clearance = depth of water − draft = 21 ft − 18 ft = 3 ft.
Authority: Bowditch (Pub. No. 9), Piloting
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