Course to steer to compensate for current

Bowditch Ch. 1 §102

Bowditch Ch. 1 §102 — Introduction to Marine Navigation Dead reckoning (DR) is the determination of position by applying course steered and distance run from a known starting point. DR accuracy degrades over time and must be confirmed by external fixes whenever possible.

Bowditch Ch. 23 §2302

Bowditch Ch. 23 §2302 — Navigational Errors Set and drift describe the effect of current on the vessel's track. Set is the direction toward which the current is flowing; drift is the speed of the current. The vector sum of the intended course (course made good through water) and the current vector gives the actual course over ground.

Bowditch Ch. 24 §2401

Bowditch Ch. 24 §2401 — Currents Surface ocean currents are driven primarily by wind, with major gyres in each ocean basin. Tidal currents are driven by tide rather than wind and reverse direction with the tide.

Bowditch Ch. 24 §2402

Bowditch Ch. 24 §2402 — Currents The vector triangle for current correction is: course steered + drift vector = course made good. Inverting it: from course made good and drift, derive the course steered required to make a given track over ground.

33 CFR §164.11

§ 164.11 § 164.11 Navigation under way: General. The owner, master, or person in charge of each vessel underway shall ensure that: (a) The wheelhouse is constantly manned by persons who: (1) Direct and control the movement of the vessel; and (2) Fix the vessel's position; (b) Each person performing a duty described in paragraph (a) of this section is competent to perform that duty; (c) The position of the vessel at each fix is plotted on a chart of the area and the person directing the movement of the vessel is informed of the vessel's position; (d) Electronic and other navigational equipment, external fixed aids to navigation, geographic reference points, and hydrographic contours are used when fixing the vessel's position; (e) Buoys alone are not used to fix the vessel's position…

33 CFR §164.78

§ 164.78 § 164.78 Navigation under way: Towing vessels. (a) The owner, master, or operator of each vessel towing shall ensure that each person directing and controlling the movement of the vessel— (1) Understands the arrangement of the tow and the effects of maneuvering on the vessel towing and on the vessel, barge, or object being towed; (2) Can fix the position of the vessel using installed navigational equipment, aids to navigation, geographic reference-points, and hydrographic contours; (3) Does not fix the position of the vessel using buoys alone (Buoys are aids to navigation placed in approximate positions either to alert mariners to hazards to navigation or to indicate the orientation of a channel. They may not maintain exact charted positions, because strong or varying currents…