you don't need to do that - just download https://openflights.org/data.html https://openflights.org/data.html, and plot airport x/y to airport lat/lon directly.

you don't need to do that - just download https://openflights.org/data.html https://openflights.org/data.html, and plot airport x/y to airport lat/lon directly. Since you're doing only Europe, you don't need to do the sin/cos math do get an accurate projection