Nonlinear static aeroelastic and Trim analysis of highly flexible aircraft

The static aeroelastic responses, trim solutions and stability analysis of a high aspect-ratio all-wing aircraft without aileron nor rudder is presented. The basics of the computational framework is the coupling of a geometrically nonlinear 3D co-rotational double-spar structural model with a 3D non-planar vortex lattice aerodynamic model. Inertia relief is introduced for the first time to count for the effects of mass distribution on the static deformations of the unconstrained flying aircraft. The aeroelastic deflections, lift distributions, aerodynamic coefficients and their derivatives, as well as the trim solutions and flight dynamic roots are assessed and compared with rigid, linear and nonlinear structural models. Results show that the overall aeroelastic responses, trim solutions and flight dynamic characteristics are highly affected by structural flexibility, revealing the importance of taking into account the geometric nonlinearity in flexible aircraft design and analysis.