Influence of Calendar Environment on Fatigue Behavior of Aircraft Critical Components

To study the structure safety problem of aging aircraft, 2A12-T4 aluminium alloy specimens were used to simulate the accelerated environment test and fatigue test under different parking calendar years. The decrease rule of detail fatigue rating (DFR) was calculated, and the degeneration model for fatigue critical components was established based on dynamic <em<S-N</em< curve method. With the established model, the fatigue lives of specimens under different parking calendar years were compared with the fatigue life of the same specimen from retired aircraft. The result shows that the obtained predict fatigue life from life prediction model based on dynamic <em<S-N</em< curve and DFR method is in good agreement with the test, and the fatigue performance of aircraft cirtical components would declines with the extension of cumulative parking calnendar time.