USCG Exam PracticeDead reckoning — DR plot maintenance
A new DR position must be plotted at every course change, every speed change, at each fix, and ______.
- A. at least once each watch
- B. at least once each hour, less often in pilot waters
- C. whenever the helmsman is relieved
- ✓ at least once each hour, more often in pilot watersCorrect
Why D is correct
Bowditch §801 specifies the four mandatory update events and adds the hourly minimum, with increased frequency required in pilot waters — not reduced frequency.
Cited:Bowditch Ch. 8 §801