as a truck driver and this is no defence these truck's are so noisey if something does come off the truck he may not of heard it cant look in your mirror's all the time. as for failing to stop did you try to stop him did you get his attention if you did and he drove off he is a disgrace to our trade .if the police do get him i think it will be hard to prove he left the sceen of an accident he will say he did not see it no excuse i know but they will have him for unsafe insecure load. just hope you are ok mate you were very lucky thou mate. DOWN WITH BAD DRIVER'S