Abstract: After briefing the merits and demerits of some commonly used methods to char acterize air craft maneuverfatigue loads, the Markov frequency matrix is examined in the view to describe load state transition events. Theform and construction of the Markov matrix are illustrated by an example, and the method to fill the matrix by computer programming is explained. According to the graph theory, the Markov matr ix is re-examined as the adjacentmatrix of weighted multiple directional graphs with Euler ian loop. The features of Markov frequency matr ix and ther equirements for a matrix to r ealize fatigue load history construct ion are outlined, and an example of processing datafor an aircraft flight mission was presented. Discussions showed Mar kov matrix characterization has more useful information than other forms have and is yet easily transformed into other forms.

Key words: fatigue load, load history, Markov matrix, graph theory, adjacent matrix, Eulerian graph