The nose of the aircraft is too dark and the eye is drawn away from it. Plus the port engines are almost indistinguishable from the port wing due to their both being too dark.

Still quite nice though.

I agree with spitfire, although I really like what's below and slightly left of the right engines. What exactly is that? It intrigues me!

I think Dave really hit it precisely. I personally don't have issue with wings cut off, but placing the sun behind the pic as opposed to in front would have really increased the contrast and color depth here. One more thing, the little row of cumulus at the bottom of the cloud cover look a bit unrealistic. In truth, I think there's a lot to like in this pic. The scenery is great, and the overall aircraft perspective creates a nice mood. With lighting changes and a bit of weather modifications, this would be an even better pic.