The performance requirements of today’s missile are increasing by imposing more sever demands.The high maneuverability, controllability, and good tracking of target, are among those requirements.However, meeting those requirements is not an easy task, since the behavior of the missile whileflying in air, is very difficult to predict, because of the interaction between the aerodynamics and theflight dynamics.This paper puts the emphases on some aerodynamic and flight dynamics aspects, especially thoserelated to large angles of attack, and the resulting flight dynamics problems.At high angles of attack significant flow phenomena take place, among these phenomena; flowseparation, unsteadiness of the flow, formation of fore-body and wing vortices, time-dependent andhysteresis effects, and non-linear behavior of the aerodynamic forces and moments.Since the dynamic problems at high angles of attack are the logical consequence of the interactionbetween the highly complex flow field over the missile, and the dynamic characteristics dictated bythe geometry of the configuration, the flight dynamics phenomena associated with flying at highangles of attack, need to be considered when designing a control law to control the path of themissile.To asses the significance of some selected stability derivatives, and their effect on the predictedmotion, a numerical simulation of the six-degrees-of freedom equations of motion is performed.The numerical integration of the full non-linear equations is done using the fourth order Rung-Kuttamethod.Even though reliable data for missiles is not readily available in the open literature, some data whichare believed to be representative of high performance configuration (such as a missile) are used in thepresent study.Results indicate the importance of non-linear cross-coupling stability derivatives; hence theinclusion of such effects in the control law is very significant in order to predict the motion of themissile to an acceptable degree of accuracy.
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