Flight dynamics of transport aircraft equipped with flared-hinge folding wingtips

This paper studies the influence of flared-hinge folding wingtips on the aerodynamic derivatives and flight dynamics of a narrow-body transport aircraft. In addition, the influence of fold angle, hinge-line angle (flare angle), and wingtip size on wing loading is assessed. The Tornado vortex lattice method is used for aerodynamic predictions and to estimate the stability and control derivatives. First, the aircraft is assumed rigid, and different hinge angles, fold angles, and wingtip sizes are considered. Then, structural flexibility is considered by coupling Tornado with a linear structural finite element solver to facilitate quasi-static aeroelastic analysis. The quasi-static deflections method is used to study the flight dynamics of the flexible aircraft. The effect of the flared-hinge folding wingtips on the longitudinal and lateral-directional flight dynamic modes of the rigid and the flexible aircraft is compared and contrasted. Furthermore, the variations of longitudinal trim settings and roll response with flared-hinge folding wingtips are assessed.