Flutter Failure Risk Assessment for Damage-Tolerant Composite Aircraft Structures

The quantitative assessment of the effects of damage and material degradation on the dynamic aeroelastic reliability of composite aircraft has become more challenging in recent years due to the increased use of composites in main structural components of passenger aircraft. This paper presents a method for quantifying the flutter reliability of aircraft composite structures in the presence of multiple uncertainties. Automated rapid simulation tools for predicting flutter speeds of composite airframes subject to multiple uncertainties serve a key role and are used in Monte Carlo simulations. A thorough discussion is presented of the flutter uncertainty of composite aircraft covering material degradation, damage, repair, and design and certification practices, as well as maintenance procedures. The effectiveness of the method and its potential are illustrated using a composite tail/rudder structure representing a typical passenger aircraft structure. Conclusions are drawn and recommendations for future work are made.