A design chain for preliminary design of hybrid-electric and full-electric aircraft allowed to explore different possible innovative concepts aiming to find out the best configuration with respect to top-level requirements. The aim of this work was to opportunely describe how it was possible to obtain a high-fidelity estimation of mass and stiffness properties for main wing components (spars, ribs, skin and stringers). The configuration under consideration hereinafter is a full-electric configuration of a commuter 19 passengers, which provides for 8 electric motors distributed along the wingspan, with two tip electric motors as a primary propulsive system. The design starting point was the estimation of flight loads, which come out from V-n diagram. Afterwards, in order to refine the first level weight estimation (based on analytic method) a dedicated high-fidelity structural analysis was performed, which allowed a higher-fidelity strength assessment as well. This approach allowed to verify the structural efficiency of the wing within the aircraft flight envelope and to optimize the structure components.

Shimmy oscillations are undesired vibrations in aircraft landing gears. In this chapter, the onset of shimmy vibrations, marked by Hopf bifurcations, is investigated in the parameter space of high-fidelity, flexible multibody landing gear models. Such a bifurcation analysis is performed by combining the Virtual.Lab Motion multibody solver with the numerical continuation software AUTO. The resulting quasi-2-parameter bifurcation diagrams, involving aircraft velocity and normal load, are verified using conventional time-simulation methods and are shown to be computationally more efficient. A sensitivity study reveals the influence of design parameters, such as the shimmy damping coefficient, mechanical trail, and steering actuator stiffness, on the occurrence of shimmy.