I get the concept of 19 just having problems with it. You have to nudge them slowly so they are all touching the ground, anything on the ground will not be picked up by the fans.
All you have to do is remember that on level 1 all the incoming planes are at 6000 feet so drop any planes in those areas to 5000 or less. Level 2 some come out at 5k and some at 6k so keep them below 4k. And if there was a speed up thing that would destroy the realism of the game.
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