Modeling ATM as a Complex System

The whole ATM system can be decomposed into three major interacting subsystems : the societal subsystem that contains the society constraints such as airlines, the technical subsystem that contains all technical infrastructures supporting the functioning of the ATM system, and human subsystem that includes all human components of the whole system, from flow managers to supervisors, pilot and controllers. ATM can be modelled as a set of components of different subsystems in mutual interactions in order to accomplish the mission of simultaneously maintaining safety and sustaining growth. The ATM system can be defined as a complex system because its behavior depends on a complex combination of various sub-systems performing complicated functions. The evaluation of the impact of each function on the overall ATM system cannot be performed unless a specific approach is used. As complex systems need to be studied using a systemic approach, we aim to investigate if percolation theory which studies the general properties of random structures is a able to model efficiently ATM. Two basic aspects of the problem must be specified in order to perform a coherent modeling of the ATM behavior : • proposing an adapted mathematical approach to model the ATM from a systemic point of view and define its complexity using the appropriate theories.