民用飞机安全性分析中单点失效MTBF的算法

Single failure MTBF analysis on aircraft safety assessment

安全是民航工业的生命线。按照适航规章要求,任何妨碍飞机继续安全飞行与着陆的单点失效的出现是极不可能的。传统的参数,如平均故障间隔时间(MTBF),是用来计算部件失效概率的常用参数,但由于关键安全部件可能在平均故障间隔时间之前出现故障,因此,该参数的传统计算方法对于单点失效概率的分析并不适用。提出评价单点失效概率的分析方法,即基于所给出数据样本量的大小,提出了评价单点失效概率的计算公式。给出了两个案例来进一步验证所提方法的有效性。

Safety is the lifeline of civil aviation industry. The regulations proposed by airworthiness authorities require that the occurrence of any single failure which would prevent continuous safe flight and landing of airplanes is extremely improbable. While the ambiguous description makes it difficult to calculate the occurrence of single failure in practice. The traditional parameter, mean time between failure（MTBF）, is not suitable for single failure analysis due to the possibility that critical safety components may fail before MTBF. A method is proposed to e- valuate the probability of single failure. The evaluating formula for the occurrence probability of single failure basing on sample size is given. Practical cases are used to verify the effectiveness of this method.