USCG Exam PracticeDanger bearings and danger circles
A vessel is approaching a rocky headland from seaward. Only one charted lighthouse is visible. The navigator draws a danger bearing labelled NLT 358°T from the lighthouse to the safe side of the rocks. As the vessel closes the coast, the observed bearing to the lighthouse drops to 354°T. Which statement is correct?
- A. 354°T is less than 358°T, so the vessel remains in safe water on the NLT side
- ✓ 354°T is less than 358°T, meaning the vessel has crossed to the dangerous side of the NLT bearingCorrect
- C. The danger bearing is only valid when used in conjunction with a simultaneous second LOP
- D. The vessel should advance the danger bearing along the DR track to obtain a running fix before taking action
Why B is correct
For an NLT bearing, the observed bearing must be not less than 358°T to remain safe. An observed bearing of 354°T falls below the NLT limit, placing the vessel on the dangerous side. Bowditch Ch. 7 §706 defines NLT as the minimum safe bearing value; dropping below it means the vessel is standing into danger.
Cited:Bowditch Ch. 7 §706