“…The incorporation of all three degrees of freedom results in a difficulty of quasi-steady theory, namely suitable treatment of the rotational velocity. The approach employed follows the common approach in the literature (Slater, 1969;Blevins and Iwan, 1974;Nakamura and Mizota, 1975;Blevins, 1994;Gjelstrup and Georgakis, 2011;He and Macdonald, 2016), where an aerodynamic centre is defined to emulate the effect of the rotational velocity on the aerodynamic forces using the wind velocity relative to that point. Fig.…”