| Abstract: | The results of an experimental investigation of the longitudinal stability of a model maneuvering aircraft are presented. The results for a wide angle-of-attack range are obtained in a wind tunnel flow on an aerodynamic setup of free oscillations with a single degree of freedom. It is shown that the static aerodynamic dependences of the normal force and pitch moment coefficients on the angle of attack include catastrophic transitions from one steady state into another. The salient features of these transitions are established. It is experimentally found that the loss of the longitudinal stability of the model aircraft in a flow with variation in the deflection angles of stabilizers is softly realized via the Hopf bifurcation. At high angles of attack the flow regimes are found to exist in which steady motion represents a strange attractor. |
