Abstract: In this paper,according to Matsuoka's retardation model,under the condition of short period loading,a close form solution for crack propagation life/of structure ,member is derived as followswhere,a,B and r are coefficients and exponents of Walker's formula for crack propagation rate, n =B + y,p is the number of program blocks per loading period, Ni is the frequency of loading of i-th program block,Z（a） is the geometric factor of stress intensity factorThis method was used to predict the residual life about failure position of nose landing gear for certain type of fighters.Test showed that the computational result is lower than the mean value of experimental ones by 18% only.