Failure analysis applications in aircraft maintenance

In order to meet the airworthiness and availability requirements of an aircraft and to ensure flight safety; the service, repair, modification, revision, detection of status and inspection of that aircraft and its sub-systems are called aircraft maintenance together with whole administrative activities of the operations. In the first years of aviation, aircraft maintenance was an activity that was applied as a corrective process and it had not been applied unless it was indispensable, however it became a planned and regular application as preventive maintenance after being understood the importance of safety concept. Failure is a condition in which a system becomes incapable of doing its expected function. Failure analysis in aircraft maintenance activities is an interdisciplinary study conducted to determine the root and secondary causes, mechanisms of a failure or an accident that has occurred, to determine and to apply effective corrective and preventive measures and to prevent the repetition of the problem through the lessons learned. In this study, the failures detected during the aircraft maintenance activities of four different aircraft components such as main landing gear cover, accessory gearbox, compressor disk and compressor shaft were analyzed. During the these failure analysis applications, different characterization techniques such as scanning elektron microscope, non-destructive inspection methods, image analysis and hardness test were used. At the end of the study, failure mechanisms were generally determined to be ductile fractures caused by fatigue and corrosion, and precautions and recommendations were developed to prevent recurrence of failures.