A risk assessment model for free flight-terminal area reduced separation

Safety levels are a vital concern as new technologies and procedures are introduced into the National Airspace System. Despite a wealth of information from flight operations and testing programs, there is no accepted method to quantify the relationship between safety levels and aircraft separation standards in the terminal area. This paper presents a modeling approach to quantify the risk associated with reducing aircraft separation. The model is used to assess the overall level of safety associated with reducing separation standards and the introduction of new technology and procedures, as envisaged under the free flight concept.