The main objective of this project is to validate the maturity level of different technologies and structural solutions, to protect the rear-end structure of a civil aircraft from different impacts associated to engine failure. The project defines two steps in approaching to this problem. The first one (level 1) considers small flat panels in order to compare different shielding solutions, whereas in the second one (level 2) full scale aircraft structures will be contemplated in order to validate the shielding solutions selected in level 1 phase.
The first part of the work has focused in preparing the experimental set-up for the experimental level 1 tests (L1). In order to perform the experimental tests, a pneumatic launcher was used. In total more than 300 tests have been performed for the L1. The experimental study has covered metals, composites, and other combinations of materials. At the same time numerical simulations have been performed to analyse the best boundary conditions for the shielding considered. Finally, in order to understand the behaviour of the tested nets, a material characterization of the different yarns have been performed.
The second part of the project was focuosed of structures more representatives of an aircraft; these included in some of the cases curvature, stringers and frames. In total around 30 impact tests have been performed of this level. In addition, a numerical methodology has been developed to perform virtual test of high velocity impacts of metallic fragments in different types of structures, both made using composites and metals. Variables such as the impact location, the impact velocity the friction… etc have been considered in order to analyse its influence in the structure behaviour.
As an overview of the results and their exploitation and dissemination, it is possible to say that this project was very important for both the Universidad Carlos III de Madrid (UC3M) and for the company Vazquez y Torres Ingeniería S.L. (VTI). The UC3M will dramatically increase its capacity of performing high velocity impact tests with the new launcher that will be one of the largest ones along Europe. This upgrade will help to increase the workload of the laboratory since the Lightweight Structures Dynamic Group could apply to other projects and also start new collaborations with other companies thanks to the better facilities. By the other hand, VTI will add the development of a large experimental launcher devices to its capacities, which could later be used for other projects, increasing its portfolio of products. This company will increase its competitiveness in the field of experimental setups developed for the aeronautic and aerospace industries. The UC3M has presented some of the results in different conferences and workshops and it will present the rest of the achievements in future meetings. It will also publish some article in specialized journals.