shall I wait until the balance sheet gets to black before i can rent some more a/c? no other oprions?
As long as you have the required cash on hand, you can lease planes. Obviously you want to make sure that your forecast balance sheet will stay positive, otherwise you'd be heading towards bankruptcy.
If I have to wait...and operating revenue is almost 5000$ for month.....how long should I wait before to have a positive balance sheet...i am a little bit confused on how long is a Mougul month.....one hour?
If your revenue for an entire month is only $5000, you're in trouble. Release gates, maybe leased planes and take care of the routes you're opening.
Monthly costs are incurred on the first of the month (or whenever you lease a plane or rent a gate). They occur only once in each month (that's probably why they are called monthly

). Daily operating profit is computed every hour in real time (1 hour equals 1 game day, 1 day = 1 game month, months in AM are all 24 days long).
Look at the upper right of your screen. Take the valur for DOP. Multiply it by 24. Deduct what your balance sheet shows as monthly costs. Is it positive? If it is, you're making money. If not, you're in trouble and measures must be taken.