Chapter 5

FIRE SUPPORT

Section III. SYSTEM AND WEAPON DATA

5-11. FIELD ARTILLERY AMMUNITION

    Each round of cannon field artillery ammunition consists of a projectile, propellant, and a fuze.

    a. Fuzes. Fuzes cause a projectile to achieve some desired effect on a target. Some of the more common types of fuzes are:

        (1) Point detonating. A point detonating (PD) fuze causes a projectile to detonate on impact with a solid object. It may also be called a quick or superquick fuze.

        (2) Delay. A delay fuze allows the projectile to penetrate a target before detonating. The fuze provides a 0.05-second delay, allowing the projectile to travel approximately 15 meters after the fuze strikes a solid object. Delay fuzes might be used to attack enemy troops under a thick tree canopy. A specially hardened concrete-piercing fuze is required to withstand the impact of firing against concrete with the intent of penetrating it.

        (3) Mechanical time. A mechanical time (MT) fuze is used when the projectile must detonate or function at some distance above the ground (an airburst). The height of burst can be adjusted by varying the time set on the fuze.

        (4) Variable time. A variable time (VT) fuze transmits a radio signal and, by measuring its reflected energy, automatically functions to provide either a 7- or 20-meter height of burst.

    b. Projectiles.

        (1) High explosive. The high explosive (HE) projectile is best used against personnel targets. The HE projectile explodes, causing the outer shell casing to shatter into many small, irregularly shaped fragments. The 155-mm HE shell has a killing radius of 50 meters.

        (2) Illumination. Illumination (illum) rounds disperse flares on parachutes and are used for illuminating a designated area or signaling.

        (3) Smoke. Smoke (M116B) rounds eject canisters that fall to the ground and burn, emitting white smoke for 40 to 90 seconds, depending on the caliber of weapon.

        (4) Burster Type White phosphorus (WP M110A2) rounds burn with intense heat and emit dense white smoke. They may be used as the initial rounds in the smokescreen to rapidly create smoke or against material targets, such as Class V sites or logistic sites. It is against the law of land warfare to employ WP against personnel targets.

        (5) Dual-purpose improved conventional munition. The dual-purpose improved conventional munition (DPICM) round is available for 155-mm howitzers and now constitutes the largest percentage of the basic load of these weapons. The DPICM round disperses a cylindrical submunition that detonates on impact as a small shaped charge (capable of penetrating 2.5 to 3 inches of armor) with the outer-casing fragmenting with a killing radius of 5 meters.

        (6) Rocket-assisted projectiles. Rocket-assisted projectiles (RAPs) extend the effective range of cannon artillery. RAP rounds exist for 105-mm, 155-mm howitzers.

        (7) Laser-guided field artillery projectile (Copperhead). Copperhead is a 155-mm cannon-launched guided projectile (CLGP) with a shaped charge warhead and a laser seeker. When fired at a moving or stationary hard point target, Copperhead homes in on laser energy reflected from the target during the final portion of its trajectory. Laser energy is provided by a remote laser designator that may be ground, vehicular, or aerial mounted. Optimum use of Copperhead is against multiple targets in large target arrays outside the range of maneuver direct-fire weapon systems.

        (8) Family of scatterable mines. There are two types of FA-delivered FASCAM: area denial artillery munitions (ADAM), containing antipersonnel mines, and the remote antiarmor mine system (RAAMS), used against lightly armored vehicles. Both are available only in 155-millimeter. FASCAM has two preset self-destruct times: short duration and long duration. The corps commander has the authority to employ FASCAM; this authority may be delegated to brigade level for long-duration mines and to battalion level for short-duration mines.

            (a) Area denial artillery munitions. The ADAM round ejects 36 mines over the target area. After each mine comes to rest on the ground, it deploys seven 20-foot sensor triplines. Disturbing a tripline causes the mine to propel a bomblet 2 to 8 feet above the ground where it detonates, projecting approximately 600 fragments in all directions. If the mine is not triggered within its preset time, it automatically self-destructs, thereby clearing the area.

            (b) Remote antiarmor mine system. Each RAAMS shell expels nine mines over the target area. Any metallic object (for example, a tank or self-propelled vehicle) passing over a mine causes it to activate and destroy or damage the equipment. If the mine is not triggered within its preset time, it automatically self-destructs, thereby clearing the area. Some of the mines have antidisturbance firing mechanisms that cause casualties if disturbed by enemy personnel attempting to clear the mine area.

5-12. CHARACTERISTICS OF FIELD ARTILLERY