Seems like the WB wasn't set correctly considering the cloudy conditions since it's dark. Good composition though, nice take on the challenge theme and the plume of exhaust/smoke/whatever adds action and movement to the shot.
I really like this picture. and it taken by it's self is a great photo, but given that there is one very close to yours, I have to say theres is better. I could never pull a shot like this off Great Job. 8
Great air shot. I wish they were a tad more focused. I do like the interesting take on the challenge though. The smoke blends into the clouds - nice idea.