Note :
Traverse sailing combines the plane sailing solutions when there are two or more courses and determines the equivalent course and distance made good by a vessel steaming along a series of rhumb lines.
Middle- (or mid-) latitude sailing uses the mean latitude for converting departure to difference of longitude when the course is not due east or due west.
Middle-latitude sailing combines plane sailing and parallel sailing. Plane sailing is used to find difference of latitude and departure when course and distance are known, or vice versa. Parallel sailing is used to interconvert departure and difference of longitude.
