Flight testing verification of lateral-directional dynamic stability of gliding birds due to wing dihedral

Purpose Unlike conventional aircraft, birds can glide without a vertical tail. The purpose of this paper is to analyse the influence dihedral angle spanwise distribution on lateral-directional dynamic stability by simulation, calculation in development bird-inspired aircraft and flight testing. Design/methodology/approach gliding magnificent frigatebird ( Fregata magnificens ) was selected as study object. geometric mass model object were developed. Stability derivatives moments inertia obtained. assessed under different distributions angle. A developed, test carried out verify analysed results. Findings results show that changing has mode stability. All configurations have convergent Dutch roll rolling mode. key role achieve spiral Flight well-convergent Practical implications theory its may explain mechanism birds. Originality/value This helps improve understanding bird provides bio-inspired solutions designing.