USCG Exam PracticeTides and currents — predictions and corrections
A vessel is steering 045°T at 8 knots through the water. A current with a set of 090°T and a drift of 2 knots is acting on the vessel. Which of the following best describes the navigational relationship between these vectors?
- ✓ The course steered plus the drift vector equals the course made goodCorrect
- B. The course made good plus the drift vector equals the course steered
- C. The drift vector alone determines the course made good regardless of course steered
- D. Set and drift are applied only when correcting for leeway, not current
Why A is correct
Bowditch Ch. 24 §2402 states that the vector triangle for current correction is: course steered plus drift vector equals course made good. The vessel's actual track over the ground is the vector sum of its water track and the current vector.
Cited:Bowditch Ch. 24 §2402