The present Flight Safety Expert System is an innovation of the flight safety analysis software to improve the flight data analysis in the Flight Operations Quality Assurance (FOQA) program. The system has the capability to provide the causes of flight events in details and to detect the potential problems of aircraft health through the monitoring management. Through application of aerodynamic and flight dynamic principles, abnormal flight conditions are analyzed to provide quantitative metrics that may define safe operational limits. An example of analysis showing the predicted stability and control characteristics in wind-shear encounter and pilot-induced oscillations for a jet transport is presented in this paper. It is suggested that specifying the magnitude of crosswind only as the limit for safe operation in flight manual is inadequate. Satisfaction of proper stability and control characteristics in time-varying crosswind will play a role in developing the new operational criteria.