The game is good but there are multiple bugs I noticed, namely with regards to the use of 4-bit data types for numbers. For instance, if in one period you have profits of over 2.some trillion (numbers do not show to significance below 1000, so its 2.some billion thousands) you will end up with losses. Theres a similar issue in the personnel costs except it appears those may be 2-bit data types. This is very predictable and should be workable but theyve chosen not to solve this. This doesnt hugely detract from the gameplay, you will have won the game before these become issues, but it is annoying for when you continue playing.
Also a poor design choice in buying aircraft, you have to hit a button for each aircraft you want to buy. If, for instance, you wanted to buy 1000 aircraft at the same time, youd have to hit the same button 1000 times.
That said, this game is fun and you wont encounter many problems if you only play until you win the game and then quit. However, once you figure out how to play properly you can win on the hardest settings from any starting location within just 5 years of starting. It becomes very easy.