Error Modification In Trajectory Prediction Of An Unguided Rocket

Abstract

           In this paper, we will discuss the Error Modification in Trajectory Prediction of an unguided rocket which helps in explaining the importance of the production accuracy of the rocket and the advantage of using guided rockets. Total dispersion of the rocket is mainly due to three effects. The first dispersion is the result of  production inaccuracy of the rocket, which includes mass of the propellant, total mass of the rocket, lateral and axial moments of inertia, composition inaccuracy and resultant (COG) center of gravity. Because of the fluctuations in wind profile, second dispersion occurs during free flight phase. The third dispersion is the result of tip-off from the rocket launcher, atmospheric disturbances, fin and thrust misalignments and launcher deflection.

In this study, calculation of  trajectory was developed with the help of (six degree of freedom) 6-DOF model at different flight and mass properties for the prediction of the trajectory parameters and dispersion of an 122mm unguided rocket. To show the importance of trajectory analysis which may be helpful to avoid flight mistakes, simulation software was used. And also with the help of this analysis, parameters which are acting on a rocket can be known during its flight time.