A lot of countries made planes in WWII, you gotta name them by the plane that they mainly produced, or the most famous one.
Czechoslovakia, Austria and Ethiopia will be counted as countries in WWII, altough they didnt exist in 1939 anymore.
All named planes were originally from the country I linked them with, countries that had an airforce but only imported or produced licensed planes don't count!
Neutral countries count.
Probably doesn't include every country that produced plane in or just before WW2