Crash modeling of a light composite aircraft

Abstract

ABSTRACT The study presented here was focused on the crash analysis of light composite aircraft on relatively survivable accidents. The crash analysis approach was based on the numerical simulation using the finite element software (MSC.Dytran). The aircraft crash environment, impact terrain, impact angles and material properties were identified, and later introduced into the aircraft crash model. The background on composite materials is discussed and more focus was given to their response at high strain rates. The modeling methodology is also discussed with more emphasis on the finite element analysis approach and the failure theories behind composite materials. The failure criteria are based on assumptions considered for the classical lamination theory, and each of the failure theories in MSC.Dytran were evaluated before being introduced into the crash model. The Tsai-Wu failure criterion was found to be capable of predicting the progressive ply failure of the composite lamina. The Ravin 500 light composite aircraft model was used for the purpose of this study and four crash scenarios of impacting the aircraft onto the soil model were considered. The aircraft was impacted at the same crash velocity but different flight path angles were considered. The 10⁰, 15⁰, 20⁰ and 30⁰ crash angles together with a crash velocity of 22m/s were used. The impact approach was influenced by the previous literature; it shows that the structural damage of an aircraft during crash accident is affected largely by the crash angle. The results of each crash scenario are presented and mainly focused on the failure response of the aircraft structure. The conclusion on the crashworthiness of the Ravin 500 light composite aircraft is also drawn based on the numerical work. Details regarding the future work or recommendations for the design philosophy and means of improving the crashworthiness of the light composite aircraft are also presented. In addition, more emphasis is focused in the occupant’s space within the aircraft.