During the USS Missouri’s modernization in the 1980s, more than 100 WWII-era 20mm and 40mm anti-aircraft guns were replaced by four automated Phalanx Close-In Weapons System (CIWS) (pronounced “see-whiz”) rapid-fire Gatling guns. This new weapons system protected the ship using sophisticated radar to automatically detect, track, and destroy incoming missiles and other aerial threats.

CWIS Mount Characteristics:
Primary Function: Anti-ship missile defense
Weight: 12,500 lbs. (5,625 kg)
Type of Fire: 3,000 or 4,500 rounds-per-minute with a burst length of 60 to 100 rounds
Magazine Capacity: 989 rounds
Ammunition: 20mm sub-caliber armor-piercing projectiles using a heavy-metal penetrator surrounded by a plastic positioning sabot and a light-weight metal pusher.
Sensors: Self-contained search and track radar

DID YOU MO?: The Phalanx guns are affectionately nicknamed “R2-D2” due to their similarity in appearance to the beloved Star Wars droid.

DID YOU MO?: The four CIWS Mounts on board USS Missouri provided 360-degree coverage.

The Open Bridge on the 05 Level is where the top level of the Conning Tower is located. This part of the Conning Tower was called the Fire Control Station. The Weapons Officer’s station, known as Spot 3, was inside the Fire Control Station and was used as a backup for the 16"/50 cal. gun directors. In the 1940s and 1950s, the Air Defense Officer would have been stationed outside the Conning Tower on the Open Bridge where visibility was better. The Open Bridge is the highest level that guests can go on board. If you look towards the bow of the ship, you can get the best photo of Pearl Harbor with the Arizona Memorial just beyond the raised guns of the Mighty Mo.

DID YOU MO?: The function of the Fire Control Station was not to put out fires or other emergencies, but to aim the weapons used on board the battleship.