Reliability of aircraft structures under non-periodic inspection: a Bayesian approach

This paper proposes a Bayesian analysis methodology to determine appropriate non-periodic inspection intervals of fatigue-sensitive aircraft structures, so that their reliability remains above a prespecified minimum level throughout their service life. The methodology is based on assumptions about the probability distribution function of the time to crack initiation, the law of crack propagation, the probability of crack detection and the failure rate before and after crack initiation. The Bayesian approach proposed in this paper is unique and novel in that it allows one to utilize judiciously the results of earlier inspections for the purpose of determining the time of the next inspection and estimating the values of several parameters involved in the problem that can be treated as uncertain. Numerical simulations verify the above-mentioned capabilities of the Bayesian method.