Seriously guys, stop complaining about the pilots. You can reset all your skills at any time for free and then redistribute points as you see fit. If you're having trouble with them landing on the ground, don't take the upgrade. Later on there will be an upgrade that makes their pants EXPLODE which eliminates the issue of having them survive. Once you can afford the pilots + all the upgrades that lead up to, and including the exploding pants, get it.
@GoldenAstrix You can reset your skills at any time for no cost, then you can redistribute your cash. You can also later on, have their pants explode and that removes any issues of them lingering on the ground.
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Thank you :)! A very good answer!