With the advances in microelectronics, sensor technology, and packaging design, the reality of an artillery projectile, range correction device is conceivable. A previous report entitled “Preliminary Design of a Range Correction Module for an Artillery Shell” (Hollis 1996) demonstrated a possible concept called the D-ring range correction device. One of the main objectives of the range correction device concept was to contain all the mechanical and electrical components within a fuze-like envelope, while maintaining certain constraints that would allow the fuze to fit into a variety of artillery shells used by North Atlantic Treaty Organization (NATO) countries. Another objective of the range correction device concept was to avoid any changes within the ogive of any of the projectiles in the existing stockpile.
Range correction is achieved by a mechanism that symmetrically deploys four D-shaped blades, or drag blades, with the sole purpose of increasing drag. Estimates have been made of the percent change in drag as related to increases in frontal area. The deployed D-rings, with a spread of 80 mm, will increase the frontal area by 1.63 times. If the D-rings are extended a centimeter farther to a deployment diameter of 100 mm, the increase in frontal area is 2.39 times. An initial study by Brandon and Jara has indicated that reasonable maneuver authorities can be achieved for frontal areas of 7.3 in2 (47.1 cm2) and 10.7 in2 (69.0 cm2), which corresponds, respectively, to the 80-mm and 100-mm deployment diameters.
This report is a culmination of many design iterations, numerical analyses, shock tests, and actual cannon launchings. Most of the design iterations and numerical analyses are not mentioned in this report simply because they were stepping stones that led to the final design. Structural analyses indicate that the overall prototype design is durable enough to withstand the most severe artillery cannon launching available today. The design should be capable of withstanding 15,000 g’s of inertial set-back loads with 150,000 rad/s2 of angular acceleration. In addition, the design is also capable of deploying at a velocity of 650 m/s, while spinning at 250 cycles per second. The next step would be to fabricate the design in order to truly verify the integrity of the structure and to determine the overall effect of the deployed drag blades on the range of flight.