Continuity mistake: After separating the front car from the rest of the train, Tony attempts to stop the train from hitting some civilian cars on the road. First it shows a traffic jam with a single taxi right in the middle of it all. The taxi driver pops his head out the window and yells "Come on!" at the other cars. In this shot, he is not wearing a hat. But moments later as the train comes over the edge and Tony catches it in the Iron Man suit, the taxi driver steps out of his car to look up in fear, and suddenly he is wearing a green ball cap.
Picture added by Quantom X