The game isn't real time in the sense that your planes aren't flying right now or on the ground right now. However, you do earn money in real time (every hour). You also should know that it is accelerated time, 1 hour (real life) = 1 day (game), each game month has 24 days (i.e. 1 day (real life) = 1 month (game). You earn money from tickets every real life hour and pay most bills (maintenance, gates, leasing etc.) every real day. All this is done automatically, you don't have to land your flights or do anything - AM's virtual pilots are quite capable of doing that themselves. What you have to do is acquire planes, create routes for them and edit the fares on those routes (and eventually replace the planes with bigger better planes). The game is not so much based on the individual running of specific planes/routes but rather management of an entire airline.
By the way, In Service means the plane is owned and operated by your airline (or owned but not yet flying for). As opposed to being leased out/in or on sale.
