Aerodynamic compensation of the modified guided anti-tank missile configuration

Existing old generation anti-tank missiles with single shaped-charge warheads have limited applications against modern tanks with explosive reactive armor. In order to increase the efficiency, the improved versions of the warheads have been developed. The modification of the missile warhead is related to the front part of the missile, while the rear part with the motor and the missile control system remain the same for all modified missiles. The basic requirement is to use the existing guidance and the control system for both the original and the modified missile. The criteria to determine the required derivatives of the aerodynamic coefficients of the modified missile in order to compensate the change of the missile shape, mass and centre of mass, are defined in the paper. The initial values of the required derivatives of the aerodynamic coefficients are derived from the trimmed flight condition, while final tuning is done by the analysis of the stability of the guidance loop. Based on the required derivatives of the aerodynamic coefficients, the aerodynamic configuration of the missile is redesigned by the semi-empirical method and a CFD simulation. The calculated aerodynamic coefficients of the selected aerodynamic configuration are compared to the wind tunnel experiments. The validity of the design method given in the paper is proved by flight test experiments.