Investigation of multibody flight dynamic modes of an aircraft with flexible folding wing tips

The aerodynamic efficiency of an aircraft can be improved by adopting wings with a very high aspect ratio. However, the limitation to the wing size imposed by airport regulation and the increased structural weight required to support the extra aerodynamic loads produced by high aspect ratio wings need to be carefully addressed. To solve these issues, the concept of aircraft with semi-aeroelastic hinges which enables floating wingtips has been recently proposed and has attracted the attention of many researchers. However, this study provides new insights into this idea from the aspect of constraint loads at the hinges. In this work, using a multi-body dynamic simulation and a nonlinear quasi–steady aerodynamic model, an aircraft with articulated wings has been mathematically modelled, with the aircraft being composed of three rigid parts. This multi–body formulation enables one to account for finite rotations of rigid folding wing tips in addition to the traditional flight dynamic modes. Despite having a relatively small folded wing tip mass in the case study investigated here some changes have been observed in the flight dynamic behavior of the aircraft. A systematic study was carried out for different values of hinge flare angle and wingtip mass.