This invention relates to a computer network for calculating the true aircraft cornering friction coefficient of an aircraft runway or taxiway using the data collected by and available in the aircraft Flight Data Recorder (FDR) or other flight data management system, for example, the Quick Access Recorder (QAR). The invention may optionally distribute to personnel in the ground operations of an airport and airline operations, including but not limited to aircraft pilots, airline operation officers and airline managers as well as airport operators, managers and maintenance crews, the most accurate and most recent information concerning the true aircraft cornering friction coefficient to aid in making better and more accurate safety and economical decisions.