borrellig/Aeroelastic-Investigation-of-a-Utility-Aircraft

The following project aims to present the results obtained after a Structural-Aeroelastic analysis of the Twin Otter DHC-6, presenting also alternative designs which can lead to better development. Starting from a given FEM model it was possible to extend it in order to design a new structure. Equations of Motion for a flexible body were employed to derive important relations to proceed with the investigation. First, these allowed to demonstrate that the chosen design is not affected by aeroelastic instabilities, i.e. that divergence and reversal speeds are acceptable, whilst flutter is not encountered. Furthermore, it was proved that the wing can withstand significant loads all over the flight envelope. Improvements were achieved by implementing a tapered spar design and a reduced wing box thickness, making it possible to significantly increase the maximum payload allowed. Still, a similar investigation to the previous one was carried out, validating the new structure and pointing out stresses as the main limiting factor.