USCG Exam PracticeDead reckoning — DR plot maintenance
Which statement best describes the primary limitation of dead reckoning?
- A. It requires simultaneous lines of position from two or more objects.
- ✓ Its accuracy degrades over time and must be confirmed by external fixes.Correct
- C. It cannot be used in open ocean waters.
- D. It is only valid when electronic navigation is unavailable.
Why B is correct
Bowditch Ch. 1 §102 states that DR accuracy degrades over time and must be confirmed by external fixes whenever possible. DR is not restricted to any particular waters, and it does not require LOPs.
Cited:Bowditch Ch. 1 §102