The common issue in aviation is:
Some point of interest (e. g. location of fixes, obstacles, airspace boundary definition) are not given directly as pair of coordinates but their location is defined as combinations of distance (in various units), direction (true or magnetic) against specified point (waypoint, navigation aid, runway threshold) with defined latitude and longitude.
And reverse problem might occur as well: location of two points are given but we need to know what are direction and distance between them.
Because distances are usually large, simple calculation that is used in Cartesian coordinate system will give you wrong results, because Earth is not flat.
Luckily, those problems are also well known in geodesy, where are known as direct and inverse geodetic problem on the ellipsoid.
One of the solution that is pretty easy to implement is Vincenty’s iterative formulas, more information you can find https://www.ngs.noaa.gov/PUBS_LIB/inverse.pdf
The module avaiation_ellipsoid_calc_tools contains both solution: direct and inverse and source code is available at: https://github.com/strpaw/aviation_gis_tools in avaiation_ellipsoid_calc_tools.py file.
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