A system and method for receiving a first set of data for a plurality of aircraft landings at an airport, receiving a second set of data corresponding to the plurality of aircraft landings at the airport, the second set of data being received from a passive radar data source and comparing the first set of data to the second set of data to generate rules for analyzing additional data received from the passive radar data source. Also, a system and method for receiving passive data for an aircraft, receiving actual data for the aircraft, comparing the passive data to the actual data based on a set of rules and assigning a confidence level to the passive data based on the comparison.