Nice sharp focus on the helicopter and thanks for not freezing the blades. It never looks realistic. Here they are bit but at least I see movement which makes it look real. Nice work and good luck in the challenge.
Good depth of field in the photo helps to bring out the helicopter. The subject has great contrast which helps it set apart from the background. Love the slight blurring in the copter it gives it a sense of flight.
Would like to see the photo straighten a bit. It would help with the composition and give even more interest to the shot.