Module rhumb 

Rhumb line (loxodrome) sailing – the path of constant bearing.

Longer than the great circle, but the constant-bearing path actually steered. A rhumb line is also the path a leg drawn on a Mercator chart represents: a straight line on that projection is a constant bearing, the property Mercator was built for. Measuring a leg drawn on a Mercator map as a great circle gives a distance that disagrees with the line under it, so route legs should use this module throughout.

Functions

bearing_deg

The constant bearing that runs from from to to, in degrees true.

destination

The position reached by holding bearing_deg for distance_nm.

distance_nm

Distance along the rhumb line between two positions, in nautical miles.