Optimisation of Energy Absorbing Subsystems for Helicopter Vertical Crashes

The experience gained in the last decades on the development of crashworthiness helicopter structures indicates that occupants’ protection can be achieved integrating different energy absorbing systems in landing gears, subfloor and seats. However, the mutual interactions between these different subsystems must be considered to achieve higher overall performances in case of crash events. This work proposes a numerical approach for the evaluation of the overall undercarriage performance, basing on an hybrid multi-body and finite element approach. A hybrid scheme of the subfloor lay-out is integrated with a multibody model of a crashworthy seat and an anthropomorphic dummy model. The modelling technique has been used to investigate and optimize the effects of local aspects on the overall crashworthy performances of the system such as the subfloor and the seat absorbing devices. Basing on the obtained results, the proposed methodology seems a promising approach to deal with the optimization of integrated structural systems, accounting for the mutual interactions of different subsystems, as well as multiple design and constructive constraints.