Failure analysis of support link leading edge AA7075-T6

Aircraft maintenance plays an important role in controlling the quality of flight as well as the safety factor during flight. Airplane wings become vital components that must always be considered. Failure on the aircraft wing will have a major impact on aviation security so it must be investigated to avoid subsequent failure. In this case, the support link leading edge on the left wing of the Boeing 747-400 aircraft was found failure during the D-check after it was used in 56,000 flight hours. The failure analysis procedure is carried out by investigating crack paths through macrograph observations and microstructures using Scanning Electron Microscopy (SEM) equipped with Energy-Dispersive Spectrometry (EDS), as well as stress analysis observation through Finite Element Analysis (FEA). From the results of micro and macro observations, it was found the crack initiation and striations on the crack surface of the support link leading edge. The results of FEA indicated a stress concentration occurred at the inner corner of the support link leading edge component. So from the whole observation of the failure analysis, it was found that the support link leading edge was experienced fatigue failure.