So the gunner must have some sound knowledge about the aerodynamic factors. But human approach is not appreciable for scenarios like moving targets. In an instance if the light ray (eye sight) bends, ie., if the gunners view is off course because of environmental parameters the gunner will target and shoots at the ghost target. Figure shows how bending light ray, ie., gunners primary view affect the shoot. Other than this the stability of the gun also affects the performance to its worst. For better performance the gun has to be stabilized in two axis. The reason for two axis control is provided in the next figure. Here we go with Fire Control Computer (FCC). FCC calculates all these parameters affecting projectile and correct the course accordingly. Probability of first hit not only depends on the projectile course correction. It also depends on the velocity of the vehicle and the tilt with respect to surface. (See fig. 5 & 6)