General Navigation
Earth and coordinates
Know the shape of the Earth, latitude and longitude, and the meaning of a great circle and a rhumb line. Know that a great circle is the shortest path and that a rhumb line crosses meridians at a constant angle. Understand the difference between the two on a chart.
Charts and projections
Know the Mercator, Lambert conformal conic, and polar stereographic projections and their properties. Know the meaning of scale, convergence, and the effect of latitude on scale. Know the difference between a conformal and a non-conformal chart.
Time and direction
Understand UTC, local mean time, and the date line. Know the meaning of magnetic variation and deviation and how to convert between true, magnetic, and compass directions. Know the meaning of track, heading, and drift.
Traps
Questions confuse great circle with rhumb line, or track with heading. Another favourite: the effect of convergence on chart plotting and the sign convention for variation (east is least, west is best).
Worked example
True course 090°, variation 5°W, deviation 2°E. Compass heading = true course − variation (west) + deviation (east) = 090 − 5 + 2 = 087°. Rule: variation west, magnetic is best (greater); variation east, magnetic is least.