Research Journal of Physics1819-3463xxxx-xxxxorgz10.3923/rjp.2007.55.59AjayiO.O.1200711This research used the Linear elastic fracture mechanics relation together with that of the stress intensity factor range after substituting the material constants A, M developed from the outcome of an experiment conducted on a high yield strength (σ_{y} = 100 Ksi (689 MN/m^{2}), critical stress intensity factor (K_{c}) = 150 Ksi [in]^{1/2 }(165 MN/mm^{2})) Martensitic steel in air environment to develop a working model which was then employed with different constant amplitude stresses and varying average crack lengths to generate data. Series of regression analysis and optimization processes were employed to create a novel model which is suitable for data analysis, generation of design consideration, evaluation and determination of damage tolerance and safe operating condition. This has been used to eliminate the many mathematical steps and processes involved in data analysis and add ease to design and evaluation.]]>Ajayi, O.O.,2003Anderson, T.L.,1995Budynas, R.,1998Courtney, T.H.,2000De Los Rios, E.R., X.J. Xin and A. Navarro,1994Dieter, G.E.,1988Dieter, G.E.,2000Ewalds, H.L. and R.G.H. Wanhill,1991Henkel, D. and A.W. Pense,2001Hirose, H.,1993Miller, K.J. and R. Akid,1996Navarro, A. and E.R. de Los Rios,1992Nelson, W.,1984Nelson, W.,1990Odukwe, O.A., O.O. Ajayi and G.O. Oluwadare,2007Pascual, F.G. and W.Q. Meeker,1997Pascual, F.G., Q. William and Meeker,1999Shaffer, J.P., A. Saxena, S.D. Antolovich, T.H. Sandars and S.B. Warner,1999Sobczyk, K.,1987Tomkins, B., H.K. Grover and T.G.F. Gray,1981