LAUSR

Abstract Landing gears of aircrafts are an essential part of the safety systems of aircrafts concerning take-off and landing. Unfortunately, several failure analysis of landing gears have been reported on literature, therefore for safety reasons the root causes of these failures must be well identified in order to avoid future accidents. This paper presents a detailed analysis of the failure of an axle from the nose landing gear of a commercial aircraft, following an accident in which the nose of the landing gear failed during landing. The failure occurred in the transition zone between the support bearing of the wheels and the clamping of the axle to the nose of the aircraft. In order to determine the causes of the failure, a material analysis was performed, followed by a detailed study of the fracture's surface both visually and using optical and scanning electron microscopies. From these observations, it was concluded that the failure occurred by an overload condition due to combined shear and bending stresses. A finite element analyses (FEA) was carried out on the axle of the nose landing gear taking into account load conditions, in order to assess the structural integrity of the component. During the FEA it was confirmed that the failure occurred by overloading due to both shear and bending stresses because the aircraft landed with the nose landing gear instead of the main landing gear.