USCG Exam PracticeDead reckoning — DR plot maintenance
A vessel steers 045°T at 8 knots. The current sets 090°T at 3 knots. The navigator wants to find the vessel's actual track over the ground. Which vector relationship applies?
- A. Course steered minus drift vector equals course made good
- ✓ Course steered plus drift vector equals course made goodCorrect
- C. Course made good minus course steered equals set
- D. Drift vector plus course made good equals course steered
Why B is correct
Bowditch Ch. 24 §2402 states the vector triangle relationship as: course steered plus drift vector equals course made good. Bowditch Ch. 23 §2302 confirms the vector sum of the intended course through water and the current vector gives the actual course over ground.