Unique Crosswind Compensated Fire Control Device for Small Arms

摘要

In order to increase the lethality of small arms, efforts have been undertaken in two different directions: Improved munitions and advanced Fire Control Systems (FCS). Our paper describes a unique and novel addition to FCS's Crosswind compensation. The adverse effects of crosswind on the ballistics of a projectile are well known, but until now could not be corrected. The crosswind influences the flight of projectiles at short and medium ranges, causing a deflection of the projectile from its aim point and thereby reducing hit probability. In the case of shooting at small targets from distances of several hundred meters the projectile trajectory is greatly affected by crosswinds. Even moderate crosswinds of less than 10 knots (5m/sec) will cause miss distances of about 25 cm for ranges of 200 meters and more than 1 meter at ranges of 500 meters. This is true for all of the commonly used small arms munitions, such as 5.56 mm (0.2 inch) and 7.62 mm (0.30 inch) caliber bullets. Measurements taken and calculations made in order to quantify the crosswind influence on the projectile's trajectory will be presented in this paper. The new FCS will perform the combined task of measuring the range to target and the crosswind along the projectile's path. Combining the ballistic parameters of the projectile and the measured information the system processor will calculate a correct aim point. The operation technique is based on transmitting a low power laser beam along the line of sight to the target, receiving the reflected signal from the target and analyzing its turbulence induced spatio temporal power fluctuations. Experimental results, which show significant improvement in hit accuracy when shooting at distances of 500 meters under various crosswind conditions, are presented.