SBIR-STTR Award

The proposed innovative research will provide an advanced stochastic framework for developing an integrated risk-based condition assessment and life prediction-analysis system for a cost effective maintenance system for aircraft components. Corrosion fatigue is a key damage mechanism. Based on the component risk predictions, the reliability of damage detection and the reliability of damage growth prediction can be assessed. The reliability measures can be used for improving safety and readiness, and reduce operation and support costs. The proposed integrated system can serve as a state-of-art probabilistic component reliability prediction system that includes all significant post-design aspects, including manufacturing defects, operational loading history, progressive corrosion fatigue damage and life consumption under interactive failure modes, maintenance activities (inspection, repair, replacement). The proposed probabilistic component design system combines stochastic stress analysis and life prediction algorithms with risk-based maintenance analysis. The system can be also used for comparing different designs in terms of risk/safety including maintenance activities or performing "what-if analysis" to see the effects of different design modifications on component failure risks, life prediction and induced costs. The proposed probabilistic approach will offer a generic engineering capability for the reliability component risk evaluation and fatigue corrosion life prediction available for all industries. It is strongly believed that the created engineering capability and software tools developed under this effort will have a rapid spread on industry markets

In this Phase II SBIR project, STI Technologies will team with APES Inc., with strong support from Lockheed-Martin Co. and Boeing Phantom Works, to develop an advanced predictive technology for USAF aging aircraft components subjected to corrosion-fatigue. The proposed work combines state-of-art stochastic modeling techniques with physics-based models of progressive corrosion-fatigue The final product of Phase II will be an integrated software system (Probabilistic Corrosion FAtigue, ProCORFA) that rapidly performs accurate component reliability and life-cycle cost analyses for military aging aircraft. To adequately approach the corrosion-fatigue damage phenomenon and take advantage of current USAF technology, ProCORFA will interface with ECLIPSE and AFGROW codes. Phase I demonstrated the reliability algorithms for B707 lap joint design, including maintenance uncertainties (inspection, replacement and repairs). In Phase II, several aircraft component types subjected to different corrosion types will be investigated in detail. Based on the computed risks and maintenance event costs, an optimal-cost maintenance strategy for aging components can be determined. The ProCORFA software can also be used to compare different designs in terms of risks and costs, or to perform "what-if analyses" to evaluate the effects of different design and/or maintenance strategy modifications on component failure risks, remaining life and induced costs.

Keywords:
LIFE-COST ANALYSIS, COMPONENT DESIGN, CORROSION, FATIGUE, LIFE PREDICTION, RISK ASSESSMENT