Abstract: The invention provides an apparatus for processing radar returned video signals in the vicinity of an airport including at least one runway and at least one vehicle roadway intersecting the runway, in order to assist air traffic controllers in detecting potential hazardous situations. Radar returns from each of plural geographic monitored locations are compared with a simulated return for each corresponding location to detect a moving object at any of said geographic monitored locations. The presence of a moving object at one of such locations may be indicative of a hazardous situation, and in that event, the air traffic control operator may be warned by an alarm or the like.