Liano, G., Castillo, J. L., García Ybarra, P. L. 2016. Steady states of the rolling and yawing motion of unguided missiles. Aerospace Science and Technology 59, 103-111 DOI: 10.1016/j.ast.2016.10.016
The nonlinear phenomena associated with resonance instability, lock-in or catastrophic yaw, in the free flight of finned bodies is of critical importance with regard to flight performance. These phenomena are related to the presence of large-amplitude steady-state solutions of the yawing motion, which can serve as attractors for some trajectories, preventing the body from attaining the design steady state of low amplitude. The motion at large amplitudes can only be explained on the basis of a nonlinear roll dependent yaw moment. This roll dependence appears when considered cubic or higher order terms in angle of attack. The effects of cubic contributions have been investigated by previous authors, but no attempts have been made to incorporate higher order terms. This paper examines the impact on the steady states of the coupled roll-yaw motion when using a high-order roll-dependent yaw moment, shown to be realistic up to angles of attack near 30, in an effort to provide tools to explore the dynamic free-flight behavior in the high angle-of-attack regime. Moreover, a methodology based on experimental or numerical data is presented, which can suppress angle of attack restrictions with the possibility of obtaining realistic equilibrium points of any amplitude. (C) 2016 Elsevier Masson SAS. All rights reserved.
