Abstract:

ESDU 83006 provides a method for calculating the contributions of the vertical stabilising fin of an aircraft to the sideforce, yawing moment and rolling moment derivatives due to rate of roll. The method is applicable for subsonic flight speeds when the flow over the aircraft is wholly subsonic and fully attached. The tail assemblies covered are those where a single fin is located on top of the aircraft rear body and in the plane of symmetry, with a tailplane, if present, mounted either on the fin itself or on the rear body. The aircraft is assumed to be in the 'clean' configuration with no flaps or slats deployed. The method is semi-empirical. It uses some theoretical calculations of the spanwise loadings arising on isolated fin-tailplane arrangements rolling at zero angle of attack to estimate the magnitude and centre of pressure position of the damping force on the fin. Corrections in terms of the mean sidewash occurring at the fin are made to allow for the presence of the wing and body and for angle of attack variations, with the magnitudes of the corrections being deduced from comparisons with a large number of wind-tunnel test results.