I am trying to get the following information. I would like to know for each day how many aircraft have taken off and departed from a specific country. This information should be up to date and possibly have also some historical time series as well (for example the last month). I know i could get such information by paying some services like Flight Aware or FlightRadar24 but I need to do it for free. I tried OpenSky but the API doesn't offer much information (just time, lat/lon, origin). Do you know a possible way to gather such information? It doesn't need to be machine readable as long it has the info.
Thanks in advance.
estDepartureAirport
contains the "ICAO code of the estimated departure airport". The first two letters of the ICAO code tell you pretty much, which country you are in. Some countries have more than one prefix, but I'm sure, you'd find a list somewhere on the net. $\endgroup$