With this filter enabled, the map would only show aircraft flying high enough and close enough to be above the horizon from a given location. The visibility/horizon could either be calculated for an idealized ellipsoid or modified with local topology data. In addition to filtering which aircraft are shown on the map, the table listing could include a column for each aircraft's apparent angle above the horizon.
-- a1, Jan 20 2024

tar1090 https://github.com/wiedehopf/tar1090
provides a web interface for use with ADS-B decoders. [a1, Jan 20 2024]

random, halfbakery