Flight safety is the most important operational and technical characteristic of the air transport system, which is influenced by many factors, unstable and random in nature, which, as a rule, are interconnected with each other. The management of any property of a complex dynamic system, including the safety property of an operated air transport system, provides, as a mandatory procedure, a quantitative assessment (measurement) of the current value of the parameters by which control is carried out, since, in accordance with the basic postulate of management, to control is possible only by what is measurable. During the operation of the aircraft, information is accumulated about the state of the automatic exchange, as about the object of study. In this case, to some extent, the uncertainty in the knowledge about the object is eliminated. The main reason for uncertainty is the randomness of phenomena and processes. Obviously, there are no phenomena or events in which there are no elements of chance. No matter how accurately and carefully the operating conditions of the aircraft are recorded, it is impossible to ensure that with repeated (continued) observations, the results completely and exactly coincide. Random deviations inevitably accompany any natural phenomenon. Unlike common practice random elements cannot be neglected, especially since the result of operation depends on a large number of factors and even more combinations of them. It is necessary to study random phenomena, investigate patterns and find out the causes of random occurrences in a regular phenomenon. Finding any stable patterns is usually very difficult. However, if we consider a sequence of a large number of observations, then some rather interesting properties are revealed: individual (separate) observations are unpredictable, and the average results show stability or a pronounced trend of change (pattern of change) characteristic of dynamic systems.