The prediction of aircraft structure service life is of great importance to safety of aircraft structure and human beings. The relation between aircraft structure service life and reliability can be found by utilizing the fatigue scatter factor of whole life. Only when the service life satisfies the requirements of reliability, can the safety of airplane be ensured. The fatigue scatter factors of the service life accords with lognormal distribution and Weibull distribution were studied to provide important reference for predicting the safe service life of aircraft structure.

The project presents the theory of active reliability-based design for predetermined life targeted at their economic life. The structural reliability is designed from the view point of economic efficiency and maintainability requirements, so that the destruction of products led by fatigue and fracture is eliminated to the highest possible degree to provide the longest life, the highest reliability and the lowest cost. The reliability assessment of conventionally finished product is developed into an active reliability design at preset life, which is implemented before the design of products is finalized, to improve the safety and reliability of structures.