Jet Age and Dawn of the Millenium are easy compared to Modern Times. In the period 1960-2000, you can just set up your airline and just keep on a look out for marauding competition. Your airline will mostly run itself and make $$. In Modern Times, you have to actively manage your airline almost constantly. I havent added a plane in nearly a year game time, but I am constantly adjusting fares to reflect fuel prices and looking at adjusting advertising, and personnel expenses to keep from going under.