The OpenSky Network was initiated in 2012 by researchers from armasuisse (Switzerland), University of Kaiserslautern (Germany), and University of Oxford (UK). The objective was (and still is!) to provide high quality air traffic data to researchers. By now, the OpenSky Network has become a non-profit association based in Switzerland and is supported by a growing number of contibutors from industry and academia. Researchers from different areas are using the data that is provided by people from all around the world.
You can even track planes' filed flight plans from their API: https://opensky-network.org/api/routes?callsign=EDW200E
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