Lifetime Assessment of Aircraft Structural Components in Coastal Environments

Abstract

To explore the lifetime of aircraft structural components in coastal environments, the failure process of LY12CZ aluminum alloy stringer servicing in the coastal environment of the Fiji Islands was analyzed. The whole lifetime process of structural components was divided into four stages: coating failure, pit nucleation and growth, short-crack growth, and long-crack expansion. The failure time of coating was assessed by way of formulation and implementation of accelerated environmental spectrum, and a four-stage model was established by analysis of pitting corrosion and derivation of the crack expansion equation. The assessment was virtually consistent with the stringer. Findings showed that pit nucleation and growth and short-crack growth account for approximately 75 % of the entire lifetime. After aircraft structural components have been in service for approximately 14 years, the crack will expand rapidly to the extent that the components will rip apart.