Life prediction of helicopter planetary carrier plate fatigue crack propagation

Planetary carrier plate (referred to as the carrier) is one of the most important components of a helicopter transmission system, and its reliability is critical for the helicopter flight safety. Subjected to a variety of factors, the development of the carrier fatigue crack fault is difficult to be diagnosed or prognosed. In order to predict the fatigue crack life of the carrier, crack fault mechanism is studied and a log-linear method is developed in this paper. The crack propagation process is discretized by combining the Paris law with Miner rule, then the fatigue crack damage is accumulated. And the value of the cracked carrier remaining service life corresponding to different crack length is obtained. Calculated numerical results are compared with simulation data using the commercial finite element software ANSYS Workbench fatigue life calculation module, which validates good accuracy and effectiveness of the developed method in predicting the remaining life of a cracked carrier.