Design and Testing of a Fiber-Metal-Laminate Bird-Strike-Resistant Leading Edge

One of the major concerns related to flight safety is the impact of birds. To minimize the risks, there is the need to improve impact resistance of aircraft by developing high-performance materials and better structural design of aircraft structures. Because of their remarkable impact properties, fiber metal laminates with layers of aluminum alloy and high-strength glass-fiber composite are potential candidate materials to be employed for aircraft structures susceptible to bird strikes. This paper describes an experimental and numerical campaign aimed at assessing the bird strike resistance of a fiber-metal-laminate-composite leading edge for the wing of a transport aircraft. Three different fiber-metal-laminate leading-edge structures were designed using advanced finite element simulations; they were manufactured and finally tested to analyze their impact-energy-absorbing capabilities. The finite element models were developed, adopting a Lagrangian approach in such a way to be able to correctly simulate impacts with large deformations and perforations of the structures and to characterize the different inelastic/brittle behaviors and failure modes of the fiber metal laminates. The numerical simulations were generally in good agreement with the experimental values, demonstrating the robustness of the developed finite element simulations in supporting the design of bird-strike-resistant aircraft structures.