Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth and closure processes. Today structural and materials engineers develop structures and materials properties using this technique. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Keyhole Specimen Test Load Histories by finite element analysis. The crack propagation simulation was based on release nodes in the minimum loads to minimize convergence problems. To understand the crack propagation processes under variable amplitude loading, retardation effects are observed.