USCG Exam PracticePlot true course and distance between two charted points
US nautical charts reference soundings to which vertical datum?
- A. Mean Sea Level (MSL)
- B. Mean Low Water (MLW)
- ✓ Mean Lower Low Water (MLLW)Correct
- D. Mean High Water (MHW)
Why C is correct
US charts show soundings in feet, fathoms, or metres referenced to Mean Lower Low Water (MLLW). The unit used is stated in the chart title and must be verified before plotting. (Bowditch Ch. 4 §403)
Cited:Bowditch Ch. 4 §403