USCG Exam PracticeVisual piloting — three-bearing fixes, danger bearings
When using radar for piloting in confined waters, which range scale provides the best target discrimination for collision avoidance?
- A. 6 nautical miles, because it shows the widest area around the vessel
- B. 12 nautical miles, because it provides the earliest warning of approaching traffic
- ✓ Short ranges such as 0.5 or 1.5 nautical miles, because they give the best discriminationCorrect
- D. Long ranges such as 6 nautical miles, because landfall detection is optimized
Why C is correct
Bowditch Ch. 13 §1302 states that short range scales give the best discrimination for collision avoidance, while long ranges are best for landfall detection. Options A and D invert this relationship.
Cited:Bowditch Ch. 13 §1302