THE following equations to the trajectory of the projectile were developed with the hope of obtaining something expressed in the simplest terms and of a wide range of application. Auxiliary tables are not required. The equations will give a close approximation of the performance of a long-point, high velocity projectile whose weight is in the neighborhood of d3/2—lbs. and velocity above 2500 f.s. They are not to be used where more exact information is available but should not develop errors in excess of 5 per cent. It is thought that the equations may prove of especial interest in connection with high angle fire. It will be noted that at an angle of elevation of 45° the sine term drops out of the equation for range, giving a very simple expression for the maximum range.
Vest Pocket Ballistics
By Lieutenant W. L. Wright, U. S. Navy