This is pretty simple to get. This achievement pops in the level where you start in the Petit-Copter, and it is the only one where you can finish the level in the vehicle. The key is not to hit the red circles from below, and avoid enemies (you can shoot them). You can land on the red circles as platforms.
This is really only difficult if you want to get all the cash. To be honest, you can get plenty of cash from the easy ones, so there's no need to get really ambitious there.