I like this game but it has serious bugs/flaws, most notably in how it handles fixed/unchangeable routes. One issue is that these routes use up a slot at the airport on each end even if the airport on the other end is shut down — this totally screws the player in “Megaregions” where an airport shut down makes the entire region inaccessible and leaves the player with literally no way to continue after playing 10-15 levels. In “Route 66,” it’s impossible to “keep all drawn routes” (one of the goals) once the fixed routes appear in Level 3—even if you have kept all drawn routes up to that point, the circle will immediately go gray as if you haven’t. Another basic gripe is that airport passenger numbers can’t be seen when the map is zoomed out, which makes larger maps really annoying to play since you have to pan and scroll repeatedly to see where the focus cities should be.
Hey there, glad to hear you enjoy playing the game and I appreciate your feedback. We tested each level and goal to make sure they are all possible to complete. While Megaregions is one of the most difficult levels in the game, you could get out of the situation you described by either downgrading other airports to upgrade the inaccessible ones or by saving more money in previous rounds so you can later upgrade those airports. For the passenger numbers, you can modify the "Show Passenger Count" setting in the preferences menu to view them at any zoom scale. Let us know if you have any more feedback or run into more issues by tapping the Support button in the preferences menu in the game.