The urgent demand for ultra-high strength aluminum alloy materials in the current aviation industry makes it extremely important to realize the localization of this material with desirable application effect. To evaluate the Initial Fatigue Quality (IFQ) of the new aluminum alloy material 7XXX commonly used in China's aviation industry, we select the Time To Crack Initiation (TTCI) and Equivalent Initial Flaw Size (EIFS) as the comparison parameters. Firstly, the fatigue tests of 7XXX fastening hole specimens for China's aircraft wings and BXXX fastening hole specimens of Russian series are conducted at three stress levels, i.e. low, medium and high, and the results show that the TTCI of the two specimens at different stress levels tend to be the same with the maximum difference being only 3.71%; the EIFS of each specimen is obtained, and the fatigue statistical method verifies no significant difference between these two values. A structural detail equivalent initial flaw model with different exceedance probabilities P is proposed to effectively evaluate the quality risk of the structural details of the aircraft. The general EIFS distribution of the structural details of the two specimens is established and compared. Both are smaller than 0.125 mm specified in China's military manual. In addition, when the exceedance probability is 5%, the general EIFS value of the 7XXX material is smaller than that of the BXXX material.
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