A m1 garand firing from a Speed boat
The Phalanx CIWS was extensively used to defend the ships in the movie. When an alien ship opened fire on the destroyer USS John Paul Jones, the Phalanx defended the ship but misses one missile, which caused the right bridge wing to be damaged. Sampson also used the Phalanx. When the other alien ship opened fire at Sampson, the Phalanx defended the Sampson but misses one missile that caused a hull breach on Sampson. Myoko also had a Phalanx but did not use it. At the night time battle, When both alien ships opened fire, the Phalanx defended John Paul Jones, but this time it was successful. When John Paul Jones lured the third enemy ship to a trap, the Phalanx engaged the third alien vessel, along with her 127mm gun, Tomahawk Missiles and .50 cal. machine guns. After destroying the third alien ship, shredders heads for the ship. The Phalanx again tries to defend the ship, but its bullets missed the objects, which caused John Paul Jones to be destroyed. The Missouri also used the Phalanx. The Phalanx supported Missouri's 16 inch guns. The last alien ship however, opened fire at Missouri. The Phalanx fails to defend Missouri which caused turret 3 to be destroyed. Throughout that fight scene, the Phalanx provided suppressive fire. Before Missouri fired at the alien's location, the last alien ship formed 3 shredders. After Missouri fired, the last alien ship also fired the last 3 shredders. The Phalanx never fired on these 3, maybe because they ran out of ammo.