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What kind of data are we talking about exactly? If be flight you actually mean live air traffic - you can read https://www.flightradar24.com/how-it-works https://www.flightradar24.com/how-it-works or https://www.kaspersky.com/blog/tracking-airplanes-how-flightradar24-works/8389/ https://www.kaspersky.com/blog/tracking-airplanes-how-flight... on the topic. Not sure there is a service that provides this aggregated data for free.