USS Missouri (BB-63) is an built for the United States Navy (USN) in the 1940s and is now a museum ship. Completed in 1944, she is the last battleship commissioned by the United States. The ship was assigned to the Pacific Theater during World War II, where she participated in the Battles of Iwo Jima and Okinawa and shelled the Japanese home islands. Her quarterdeck was the site where the Japanese Instrument of Surrender was signed, officially ending World War II.
After World War II, Missouri served in various diplomatic, show of force and training missions. In 1950, the ship ran aground during high tide in the Chesapeake Bay and after great effort was re-floated several weeks later. She later fought in the Korean War during two tours between 1950 and 1953. Missouri was the first American battleship to arrive in Korean waters and served as the flagship for several admirals. The battleship took part in numerous shore bombardment operations and also served in a screening role for aircraft carriers. Missouri was decommissioned in 1955 and transferred to the reserve fleet (also known as the "Mothball Fleet").
Missouri was reactivated and modernized in 1984 as part of the 600-ship Navy plan. Cruise missile and anti-ship missile launchers were added along with updated electronics. The ship served in the Persian Gulf escorting oil tankers during threats from Iran, often while keeping her fire-control systems trained on land-based Iranian missile launchers. She served in Operation Desert Storm in 1991 including providing fire support.
Missouri was again decommissioned in 1992, but remained on the Naval Vessel Register until her name was struck in 1995. In 1998, she was donated to the USS Missouri Memorial Association and became a museum ship at Pearl Harbor, Hawaii, where she still sits to this day.
Background and description
The Iowa class of fast battleships was designed in the late 1930s in response to the US Navy's expectations for a future war with the Empire of Japan. The last battleships to be built by the United States, they were also the US Navy's largest and fastest vessels of the type. American officers preferred comparatively slow but heavily armed and armored battleships, but Navy planners determined that such a fleet would have difficulty in bringing the faster Japanese fleet to battle, particularly the s and the aircraft carriers of the 1st Air Fleet. Design studies prepared during the development of the earlier and es demonstrated the difficulty in resolving the desires of fleet officers with those of the planning staff within the displacement limits imposed by the Washington Naval Treaty system, which had governed capital ship construction since 1923. An escalator clause in the Second London Naval Treaty of 1936 allowed an increase from to in the event that any member nation refused to sign the treaty, which Japan refused to do.
Missouri is long overall and is long at the waterline. The ship has a beam of and a draft of at her full combat load of . The Iowa-class ships are powered by four General Electric geared steam turbines, each driving one screw propeller using steam provided by eight oil-fired Babcock & Wilcox boilers. Rated at , the turbines were designed to give a top speed of , but were built to handle a 20 percent overload. None of the Iowas ever ran speed trials in deep water, but the Bureau of Ships estimated that they could reach a speed of about from at a light displacement of . The ships had a designed cruising range of at a speed of , although the 's fuel consumption figures during her sea trials suggest that her range was at least at that cruising speed. Their designed crew numbered 117 officers and 1,804 enlisted men which had greatly increased by the end of the war in 1945. Missouris crew at that time numbered 189 officers and 2,978 sailors.
Armament, fire control, sensors and aircraft The main battery of the Iowa-class ships consisted of nine /50 caliber Mark 7 guns in three triple-gun turrets on the centerline, two of which were placed in a superfiring pair forward of the superstructure, with the third aft. Going from bow to stern, the turrets were designated I, II, and III. Their secondary battery consisted of twenty /38 caliber dual-purpose guns mounted in twin-gun turrets clustered amidships, five turrets on each broadside. Unlike their sister ships and New Jersey that were the first pair of ships built, Missouri and were completed with an anti-aircraft suite of twenty quadruple mounts for Bofors AA guns, nine mounts on each broadside and one each on the roofs of Turrets II and III. Forty-nine Oerlikon light AA auto-cannon in single mounts were distributed almost the length of the ships.
The primary means of controlling the main armament are two Mark 38 directors for the Mark 38 fire-control system mounted at the tops of the fore and aft fire-control towers in the superstructure. These directors were equipped with rangefinders, although their primary sensor was the Mark 8 fire-control radar mounted on their roofs. A secondary Mark 40 fire-control director was installed inside the armored conning tower at the front of the superstructure that used the Mark 27 fire-control radar positioned on the top of the conning tower. Each turret is fitted with a rangefinder long and can act as a director for the other turrets. Four Mark 37 gunnery directors, two on the centerline at the ends of the superstructure and one on each broadside, control the five-inch guns. Each director was equipped with a rangefinder and a pair of radars on its roof. These were a Mark 12 fire-control system and a Mark 22 height-finder radar. Each 40 mm mount was remotely controlled by a Mark 51 director that incorporated a Mark 14 lead-computing gyro gunsight while the sailors that used the 20 mm gun used a Mark 14 sight to track their targets.
A SK-2 early-warning radar was fitted on the ship's foremast; above it was a SG surface-search radar. The other SG radar was mounted at the top of the mainmast positioned on the rear funnel.
The Iowas were built with two rotating aircraft catapults on their stern for floatplanes and a large crane was fitted to recover them. Initially a trio of Vought OS2U Kingfishers were carried, but these were replaced by Curtiss SC Seahawks in December 1944.
Protection The internal waterline armor belt of the Iowa-class ships is thick and has a height of . Below it is a strake of Class B homogeneous armor plate that tapers in thickness from 12.1 inches at the top to at the bottom and is high. The two strakes of armor are inclined outwards at the top 19 degrees to improve the armor's resistance to horizontal fire. In general the vertical armor plates are made from Class A cemented armor and the horizontal armor from Class B or special treatment steel (STS). The belt armor extends to the two transverse bulkheads fore and aft of the main-gun barbettes, forming the armored citadel. Part of the lower armor belt extends aft from the rear bulkhead to protect the ships' steering gear. Its maximum thickness ranges from at the top and the plates taper to 5 inches at the bottom. Unlike the Iowa and New Jersey, the armor plates in the forward transverse bulkhead in Missouri and Wisconsin have a maximum thickness of at the top that tapers to . The aft bulkhead is a consistent 14.5 inches in thickness, but does not go below the lower belt extension due it meeting the armored third deck protecting the shafts and steering gears; the steering gear is closed by another 14.5-inch aft bulkhead.
The main-gun turrets have Class B plates thick on their faces and of Class A plates on their sides. The armor plates protecting their barbettes range in thickness from to and with the thickest plates on the sides and the thinnest ones on the front and back. The sides of the conning tower are thick. The main deck of the Iowas consists of of STS. Below this deck, the roof of the armored citadel is formed by of armor in two layers. Below this is a deck of STS plates intended to stop splinters from shells that pierced the armored deck above it. The armor deck extends aft and the roof of the steering gear compartment is thick.
The underwater protection system of the Iowa-class battleships consists of three watertight compartments outboard of the lower armor belt and another behind it. The two outermost compartment are kept loaded with fuel oil or seawater to absorb the energy of the torpedo warhead's detonation and slow the resulting splinters so they can be stopped by the lower armor belt. Behind the belt is a holding bulkhead intended to protect the ships' inner spaces from any splinters that might penetrate and the subsequent flooding. For protection against naval mines, the Iowas have a double bottom that runs the full length of the ships and increases to a triple bottom except at the bow and stern.
History Construction Missouri was the third ship of the United States Navy to be named after the US state of Missouri. The ship was authorized by Congress in 1938 and ordered on 12 June 1940 with the hull number BB-63. The keel for Missouri was laid down at the Brooklyn Navy Yard on 6 January 1941 in slipway 1. The ship was launched on 29 January 1944 before a crowd of 20,000 to 30,000 spectators. At the launching ceremony, the ship was christened by Margaret Truman, the ship sponsor and daughter of Harry S. Truman, then one of the senators from the ship's namesake state; Truman himself gave a speech at the ceremony. Fitting-out work proceeded quickly, and the ship was commissioned on 11 June; Captain William Callaghan served as her first commander.
Missouri conducted her initial sea trials off New York, beginning on 10 July, and then steamed south to Chesapeake Bay, where she embarked on a shakedown cruise and conducted training. During this period, she operated with the new large cruiser , which had also recently entered service, and several escorting destroyers. The ship got underway on 11 November, bound for the West Coast of the United States. She passed through the Panama Canal a week later and continued on to San Francisco. There, additional fitting-out work was carried out at Hunters Point Naval Shipyard to prepare the vessel for use as a fleet flagship.
World War II (1944–1945)
On 14 December, Missouri departed San Francisco and sailed for Ulithi in the Caroline Islands, where she joined the rest of the fleet on 13 January 1945. She became a temporary headquarters ship for Vice Admiral Marc A. Mitscher. She then joined Task Force 58, which sortied on 27 January to launch an air attack on Tokyo in support of the planned operation against Iwo Jima. Missouri served as part of the anti-aircraft screen for Task Group 58.2, centered on the carriers , , and , during the raid on Tokyo. In addition to guarding the carriers, Missouri and the other battleships acted as oilers for the escorting destroyers, since the fleet's logistics train could not accompany the strike force during raids.
By 16 February, the task force had arrived off the coast of Japan to begin a series of airstrikes. The fleet then proceeded to Iwo Jima, which was invaded by American ground forces on 19 February. That evening, while patrolling with the carriers, Missouri shot down a Japanese aircraft, probably a Nakajima Ki-49 bomber. Task Force 58 departed in early March and returned to Ulithi to replenish fuel and ammunition. Missouri was transferred to the task group, TG 58.4 at that time.