关键词: 适航审定, 民机系统安全性评估, 基础安全性数据, 加速试验技术, 多应力耦合

Abstract: The reliability test is one of the important sources to obtain the basic safety data. Considering the actual working
environment of airborne equipment, where multiple stress act together to cause product failure and there are complex interaction, a reliability test method based on accelerated degradation of multi-stress generalized coupling is
proposed in this paper, which can directly obtain the basic safety data for airworthiness compliance verification.
Firstly, a nonlinear Wiener accelerated degradation model considering multi-stress generalized coupling is established, and the form of stress coupling is determined by combining correlation analysis. Secondly, maximum likelihood estimation and parameter optimization method based on the multi-stress accelerated degradation model is
proposed to solve the problem of multi-parameter estimation. Finally a three-stress accelerated degradation test is
carried out with an airborne LED chip as the object to realize the life assessment. The results show that, compared
with the traditional multi-stress accelerated model, the proposed method is closer to the actual working condition,
and the error is controlled within 1%, and the accuracy of life assessment is high, which can effectively solve the real airworthiness problem of missing and inaccurate of basic data.

Key words: airworthiness certification, civil aircraft system safety assessment, basic safety data, accelerated test technique;
multi-stress coupling