Encyclopaedia of Aerospace Engineering, Volume 5
Static Lateral Stability


Encyclopaedia of aerospace engineering book cover

A Filippone
John Wiley & Sons Ltd
Dec 2010, Chapter 253

This article deals with the static lateral stability and trim conditions for a fixed-wing aircraft having a conventional geometry (wing, horizontal and vertical tail plane). The aircraft is considered as a rigid body. The basic control systems are shown for a conventional vehicle consisting of a wing with aileron, a horizontal tail with elevator and a vertical tail with rudder. The simple case of a banked turn is presented. Then the pitching moment equations are derived for the wing alone and the full aircraft. Two particular cases are considered: 1.) minimum control speed in air for a flight with asymmetric thrust; 2.) aircraft in straight rolling motion without inertia coupling. The lateral stability conditions in roll are derived and the main parametric effects are discussed.