Do students pick country or fighter when picking the next question?
If country, that's awesome. Most bomb games seem to focus on letters and numbers, and seldom go beyond that (though there are a few bomb games which use completely arbitrary names - like ghost town, waterfall of shadows, etc - explaining these can take a very long time and is counterproductive at best).
As for the game itself - excellent use of graphics, and again, if you are using map for picking questions, great for practicing pronouncing country names - although, I'd seriously consider renaming USSR to Russia, since USSR no longer exists - and perhaps give students more choices. There are 3 USA fighters and 2 Japan based fighters - if you could expand that via adding more country flags/countries, it would be more useful/practical (even if the said fighters did not come from those countries).
Like others said - post it on google drive - I'd definitely be interested in getting it.