Failure analysis and fatigue life assessment of a redesigned aircraft landing gear component

Abstract

The present study deals with the failure analysis, the redesign and the fatigue life assessment of a rod end component of the North American T-2 jet trainer aircraft, nose landing gear (NLG) system. The rod ends suffer fatigue crack failures under tensile operational loading. Specifically, they are subjected to repeated loads during the take-off and landing of the aircraft which cause nucleation and growth of fatigue cracks. This study has been conducted by combining a finite element analysis (FEA) with a stress-life, fatigue design approach. A new component was designed with optimized geometry and the analysis has shown a significant decrease of maximum stress values, as compared to the corresponding values of the failed component and a subsequent increase in fatigue life without any other change in stress distribution. Furthermore, a specimen of the optimized design was manufactured and tested both functionally and operationally.