A new approach in aircraft vertical tailplane design

The paper presents a new procedure to evaluate the sideforce (and hence the directional stability and control contribution) generated by the vertical tailplane of a typical regional turboprop aircraft in sideslip and with rudder deflection. The evaluation of stability and control derivatives has a deep influence on tailplane design. To develop a new procedure that correctly estimates the effect of aircraft???s components aerodynamic interference (wing-body sidewash and wake, horizontal tailplane end-plate effect, rudder deflection), a regional turboprop aircraft geometry has been chosen, with some constraint such as fuselage slenderness, wing and tails positions, and aspect ratios. CFD analyses have been executed on hundreds of configurations. The University's computing grid SCoPE has been useful to solve the Reynolds-averaged Navier-Stokes equations in a short amount of time. Numerical results are presented in a few charts to define the aerodynamic interference coefficients and then a new procedure to design a vertical tailplane is proposed. This new approach provides a simple relationship among the aerodynamic interference factors and accurate results for turboprop aircraft configurations.