Failure Analysis of One Main Landing Gear (MLG) Sliding Tube of A320 Aircraft. Issue 1 (March 2021) - Feng, Yanpeng
Abstract: Landing gear system is one of the critical systems of an aircraft and is configured along with the aircraft structure because of its substantial influence on the aircraft structural configuration itself. Landing gear and its attachments are one of the principal structural elements and are useful for aircraft during taxiing, take-off and landing. In this research, A MLG sliding tube from one airline operated A320 aircraft, was returned by user, after a crack indication was discovered at one end of the axle arm. The part had completed about 25, 000 cycles since new and 8, 000 cycles since overhaul. The mode of crack propagation was intergranular, the crack surface was heavily corroded. A region on the outer diameter encompassing the crack had been blended prior to the receipt. No specific initiation site could be found, it was suspected based on the shape of the crack that initiation occurred from the outer diameter. Deformation was observed on the unblended inner diameter, suggesting that this location suffered a significant impact which imparted residual stress into the component. The Barkhausen noise inspection results support this.