The new micro UAVs that are so popular with the ground troops developed an unexpected problems when used in Iraq. Initially, the army and marines requested that the UAVs be painted gray, so that they would be hard for the enemy to spot (and possibly shoot down, or at least definitely know they were being watched.) But the gray paint often made the UAVs hard for their controllers to spot. Since the micro (under ten pound) UAVs are "flown" by nearby troops, the easiest way to direct the movement of the aircraft is to watch them while operating the flight controls. But in gray weather, or bad light, the gray UAVs were hard, and often impossible, to see. Some users suggested the micro UAVs be painted a bright color. But the manufacturer painted the tail white and that is being tested under different weather conditions to see if the white tail is sufficient for the operators, without making the UAV more visible to enemy troops. In Iraq it was found that the enemy was not constantly scanning the sky looking for UAVs. But user experience has shown that if you do have people periodically scanning the sky, you can often spot the mini-UAVs. A heavy machine-gun or sniper can bring them down as the UAVs  frequently fly low enough (under a thousand feet). The lower the UAVs fly, the better the pictures they get for their users. It was also discovered in Iraq that, while the mini-UAVs can fly automatic missions (from one GPS location to another), and don't then require operator control, commanders often preferred to have the operator driving the UAV so interesting items could be promptly investigated in more detail.