Experimental and Numerical Crashworthiness Study of a Full-Scale Composite Fuselage Section

Abstract

This work deals with the development of an improved numerical model, based on the explicit finite element method, aimed at investigating the energy absorption capabilities of a full-scale composite fuselage section of a regional aircraft and the related biomechanical injuries affecting the passengers. The experiment, conducted within the Italian national research project named "Innovative and Advanced Verification and Certification methods," consisted in a drop test of a fully equipped barrel performed at the Italian Aerospace Research Centre, according to the special conditions of the Federal Aviation Regulation Certification Specification 25. From a free-fall height of about 4 m, a ground contact impact velocity of 9.14 m∕s was measured. The numerical model has been developed faithfully to the experiment. Numerical analysis results, in terms of global deformations, failures, local accelerations, and biomechanical injuries, have been compared with the experimental ones to assess the prediction capability of the proposed numerical modeling procedure with a focus on improved crashworthy components for certification by analysis future purpose.

Crashworthiness of a Composite Bladder Fuel Tank for a Tilt Rotor Aircraft

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