Loxodromic navigation (from Greek λοξóς, oblique, and δρóμος, path) is a method of navigation by following a rhumb line, a curve on the surface of the Earth that follows the same angle at the intersection with each meridian. This serves to maintain a steady course in sailing.
Navigating on a spherical surface with a fixed course ( in the figure) results in a spiral path that approaches the North Pole for courses ranging from 270º to 090º and the South Pole for courses from 090º to 270º. On a nautical chart plotted according to the Mercator projection, a loxodromic course appears as a straight line.
Comparison Chart
See also Great circle navigation Windrose network Map Portolan map Marine sandglass Compass rose Isoazimuthal
References
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=6233256
External links algorithms/ assistance program for loxodromic navigation