The Phalanx Close-In Weapons System (CIWS) was developed as the last line of automated weapons defense (terminal defense or point defense) against antiship missiles.
The Block 1A and newer (pneumatic driven) CIWS mounts fire at a rate of 4,500 rounds per minute with a 1,550-round magazine. The velocity of the rounds fired is approximately 3,600 feet per second (1,100 m/s). The rounds are armor-piercing tungsten penetrator rounds or depleted uranium with discarding sabots. The Phalanx CIWS 20 mm rounds are designed to destroy a missile’s airframe and make it un-aerodynamic, thus keeping shrapnel from the exploding projectile to a minimum, effectively keeping collateral damage to a minimum. The ammunition handling system has two conveyor belt systems. The first take the rounds out of the magazine drum to the gun; the second takes empty shells or non-fired rounds to the opposite end of the drum.
