good job i really like it. here are some ideas

make it so the helicopter movies in a circle as to make it more challenging to shoot. this is fairly easy to do with a simple method where you have move forward commands mixed with turn at speed commands on a loop. you have to be careful with that though.1 thing that can happen is after crash it keeps moving in a circle, so you will want to put a command to stop that. but if you try to do that it might want to just ignore the crash routine and dive through the ground.

but overall a good job and im impressed