A So-So piece.
This animation requires some work. You'll need to increase the framerate and work on the colors. Everything is too grey and bland. A simple sky, and simply helicopter... everything was just too simple. Next time develop the objects a bit more. Maybe add in people too?
I did however like the use of sound and different scenes. The way you added little scene transitions and different view points shows your willing to make the extra 'umph'. I'd say you require more practice than you do effort.