USCG Exam PracticeDanger bearings and danger circles
A vessel is transiting a channel with a rock awash to port. The navigator plots a danger bearing of NLT 078°T using a lighthouse on the port shore. The vessel's helmsman allows the vessel to sheer, and the next bearing to the lighthouse reads 074°T. What is the correct assessment?
- A. The vessel is safe; 074°T is close enough to the danger bearing to be within compass error
- ✓ The vessel has moved to the dangerous side of the bearing and corrective action is requiredCorrect
- C. The vessel is safe because 074°T is less than 078°T and the label is NLT
- D. The danger bearing is no longer valid because the vessel's course has changed
Why B is correct
NLT 078°T means the observed bearing must be 078°T or greater to remain safe. An observed bearing of 074°T falls below the minimum safe value, placing the vessel on the dangerous side of the bearing toward the rock. Bowditch Ch. 7 §706 defines this use of NLT labelling.
Cited:Bowditch Ch. 7 §706