Abstract:

ESDU 94009 examines the process of determining the structural strength requirements for an aircraft in steady manoeuvring flight. To evaluate the shear force, bending moment and torque across the wing span and along the fuselage requires a knowledge of the mass distribution and of the loading distribution on each surface. The loading depends on the manoeuvre loads appropriate to the use of the aircraft. To provide the loading information, the aircraft is here treated as a wing-fuselage combination with the tail applying a point load acting at the aerodynamic centre of the tailplane. The tail assembly is treated as a point mass. The loading on the wing-body combination is considered as wing lift and pitching moment distributions along the span, taking account of camber, twist, incidence and pitch rate, the carry-over lift on the fuselage and the lift distributions on the fuselage and on the engine nacelles. The spanwise distribution of the chordwise position of the wing-alone aerodynamic centre is required together with the centres of lift of the carry-over lift and of the nacelle loading. ESDU 94009 develops the equations for these loading distributions in terms of the component contributions for level flight, a steady pitch-up, and a steady turn. It also discusses sources for the aerodynamic data, in particular the use of ESDU data from the Aerodynamics and Transonic Aerodynamics Series.