A method of sailing along the shortest route possible without crossing poleward of a specified latitude. A feature of great circle sailing is that a great circle route, unless it is along a meridian, lies poleward of the corresponding rhumb line route. In many ocean routes, especially in the South Pacific, a vessel following a great circle route could be carried into unnecessarily high latitudes, or indeed theoretically pass over land. In these cases, a composite route may be used. This comprises two great circle routes, the first starting at the place of departure with its vertex on a limiting parallel of latitude. The second great circle route would have its vertex on the same limiting parallel but pass through the destination. When following a composite route the vessel is sailed due east or due west along the limiting parallel between the vertices of the two great circle arcs.
composite great circle
Subjects: Maritime History.