World War II: USS Kentucky (BB-66)

USS Kentucky (BB-66), under construction in 1946. Photograph Courtesy of the US Naval History & Heritage Command

USS Kentucky (BB-66) was an unfinished battleship that was started during World War II (1939-1945). Originally intended to be the second ship of the Montana-class of battleship, Kentucky was re-ordered in 1940 as the sixth and final ship of the US Navy's Iowa-class of battleships. As construction moved forward, the US Navy found that it had a greater need for aircraft carriers than battleships. This led to designs to convert Kentucky into a carrier. These plans proved impractical and work resumed on the battleship but at a slow pace. Still incomplete at the end of the war, the US Navy then considered a variety of projects for converting Kentucky into a guided-missile battleship. These also proved fruitless and in 1958 the ship was sold for scrap.   

A New Design

In early 1938, work began on a new battleship type at the request of US Navy General Board chief Admiral Thomas C. Hart. First seen as a larger version of the earlier South Dakota-class, the new battleships were to carry twelve 16" guns or nine 18" guns. As the design evolved, the armament changed to nine 16" guns. In addition, the class' anti-aircraft complement underwent several alterations with the majority of its 1.1" weapons being replaced with 20 mm and 40 mm guns. Funding for the new ships came in May with the passage of the Naval Act of 1938. Dubbed the Iowa-class, building of the lead ship, USS Iowa (BB-61), was assigned to the New York Navy Yard. Laid down in 1940, Iowa was to be the first of four battleships in the class.

Fast Battleships

Though hull numbers BB-65 and BB-66 were originally intended to be the first two ships of the new, larger Montana-class, the approval of the Two Ocean Navy Act in July 1940 saw them re-designated as two additional Iowa-class battleships named USS Illinois and USS Kentucky respectively. As "fast battleships," their 33-knot speed would permit them to serve as escorts for the new Essex-class carriers that were joining the fleet.

Unlike the preceding Iowa-class ships (IowaNew JerseyMissouri, and Wisconsin), Illinois and Kentucky were to utilize all-welded construction which reduced weight while enhancing hull strength. Some conversation was also had as to whether to retain the heavy armor arrangement initially planned for the Montana-class. Though this would have improved the battleships' protection, it would also have greatly lengthened construction time.  As a result, standard Iowa-class armor was ordered.   

USS Kentucky (BB-66) - Overview

  • Nation: United States
  • Type: Battleship
  • Shipyard: Norfolk Naval Shipyard
  • Laid Down: March 7, 1942
  • Fate: Scrapped, October 31, 1958

Specifications (Planned)

  • Displacement: 45,000 tons
  • Length: 887.2 ft.
  • Beam: 108 ft., 2 in.
  • Draft: 28.9 ft.
  • Speed: 33 knots
  • Complement: 2,788



  • 9 × 16 in./50 cal Mark 7 guns
  • 20 × 5 in./38 cal Mark 12 guns
  • 80 × 40 mm/56 cal anti-aircraft guns
  • 49 × 20 mm/70 cal anti-aircraft cannons


The second ship to carry the name USS Kentucky, the first being the Kearsarge-class USS Kentucky (BB-6) commissioned in 1900, BB-65 was laid down at the Norfolk Naval Shipyard on March 7, 1942.  Following the Battles of the Coral Sea and Midway, the US Navy recognized that the need for additional aircraft carriers and other vessels superseded that for more battleships. As a result, construction of Kentucky was halted and on June 10, 1942, the bottom section of the battleship was launched to make room for Landing Ship, Tank (LST) construction.

The next two years saw designers explore options for converting Illinois and Kentucky into carriers. The finalized conversion plan would have resulted in two carriers similar in appearance to the Essex-class. In addition to their air wings, they would have carried twelve 5" guns in four twin and four single mounts. Reviewing these plans, it was soon found that the converted battleships' aircraft capacity would be less than the Essex-class and that the construction process would take longer than building a new carrier from scratch. As a result, it was decided to complete both vessels as battleships but very low priority was given to their construction. 

Moved back to the slipway on December 6, 1944, construction of Kentucky slowly resumed through 1945. With the end of the war, discussion ensued regarding completing the vessel as an anti-aircraft battleship. This led to work halting in August 1946.  Two years later, construction again moved forward though using the original plans. On January 20, 1950, work ceased and Kentucky was moved from its dry dock to make space for repair work on Missouri.  

Plans, But No Action

Moved to the Philadelphia Naval Shipyard, Kentucky, which had been completed to its main deck, served as a supply hulk for the reserve fleet from 1950 to 1958. During this period, several plans were advanced with the idea of converting the vessel into a guided missile battleship. These moved forward and in 1954 Kentucky was renumbered from BB-66 to BBG-1. Despite this, the program was cancelled two years later. Another missile option called for the mounting of two Polaris ballistic missile launchers in the ship.  As in the past, nothing came from these plans.

In 1956, after Wisconsin suffered a collision with the destroyers USS Eaton, Kentucky's bow was removed and used to repair the other battleship. Though Kentucky Congressman William H. Natcher attempted to block the sale of Kentucky, the US Navy elected to strike it from the Naval Vessel Register on June 9, 1958. That October, the hulk was sold to the Boston Metals Company of Baltimore and scrapped. Prior to disposal, its turbines were removed and used aboard the fast combat support ships USS Sacramento and USS Camden. 

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Hickman, Kennedy. "World War II: USS Kentucky (BB-66)." ThoughtCo, Aug. 26, 2020, Hickman, Kennedy. (2020, August 26). World War II: USS Kentucky (BB-66). Retrieved from Hickman, Kennedy. "World War II: USS Kentucky (BB-66)." ThoughtCo. (accessed February 4, 2023).