Composition -- Great choice of subject for a motion challenge, and I like the placement of the bird in the near center of the frame as this allows the full thing to show and still give it room to travel in the front of it. "Maybe" a touch more to the left would have been even better, though. Also, I think cropping it so that none of the ground was showing would have been more effective (my opinion) as it would then look like the 'copter was higher in the air.
Technique -- The contrast of the yellow and red is nice with the otherwise seasonally bland background. It causes the subject to really "snap" out from the sky. I think a slightly slower shutter speed (not much) to show more of the propellors' motion would have made this shot much more effective. To totally stop them in would have been a neat effect too, but since the idea was to show motion, showing more would have been better. Good focus and good use of available lighting.
Overall effect -- Maybe I'm biased because I really like these things (never ridden in one, don't plan to either because I terrified of heights, but i like to watch them), but I think you have chosen a subject that lends itself to the challenge well, and is appealing or at least identifiable to the audience. Good work.
Definately motion in this shot. I love the rear tail propellor thingy. The pilots are looking at you like you're crazy. lol. The color is very nice in this shot, expecially since it looks like an overcast day. Angle and framing/cropping are good. Nice shot. Good luck in the challenge.
I am just uncertain about this picture. Wondering if you should have either slowed the shutter down to have a full Blur of the rotor or Speed it up to totally stop it. I am not too sure.