Exam frequency
40%
Difficulty
3/5
Drill questions
7
Source excerpts
Bowditch Ch. 8 §801
Bowditch Ch. 8 §801 — Dead Reckoning A dead-reckoning (DR) plot projects the vessel's position from the last fix using only course steered and distance run through the water, ignoring current and leeway. A new DR position is plotted at every course change, at every speed change, at the time of each fix, and at least once each hour — more often in pilot waters.
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A navigational error check performed after a running fix reveals the vessel is set to the north of the DR position. According to Bowditch, which of the following is a recognized source of such cumulative navigational error?
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