1. A sequential-correlational method of evaluation of probabilistic characteristics of a hierarchical functional structure comprising structural elements described by respective mathematical models of structural elements, that include input and output parameters, and dependencies between structural elements described by respective mathematical models of dependencies between structural elements, that include input and output parameters; through the implementation of the process of executing simulation steps, the process which includes: generating random values of variable input parameters of mathematical models of the structural elements, in each simulation step, according to the specified rules of their variability, and determining the values of output parameters of the mathematical models of the structural elements taking into account the output parameters of linked to the structural elements mathematical models of dependencies between structural elements, in each simulation step; accumulating the simulation information about the values of output parameters of the mathematical models of structural elements, and evaluating the probabilistic characteristics of the structural elements upon completion of all simulation steps utilizing the accumulated simulation information; wherein, to implement the process of executing simulation steps, the selection of priority order of structural elements takes place, the selection which includes: identifying the input and output parameters of the mathematical models of the structural elements and the input and output parameters of the mathematical models of dependencies between structural elements; determining the sequential interdependence between the input and output parameters of all the mathematical models; determining the priority order of structural elements based on the analysis of the sequential interdependence; memorizing the priority order of structural elements; and, in each simulation step, determining the values of output parameters of the mathematical model of each structural element is performed in the priority order memorized as a result of the selection of priority order of structural elements; where, in each simulation step, when determining the output parameters of the mathematical model of each subsequent in the priority order structural element, the determined values of output parameters of mathematical models of the preceding in the priority order structural elements are inputted into all mathematical models of dependencies linking the said preceding structural elements with the said subsequent structural element.