Class overview | |
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Name: | Essex |
Builders: | Newport News Shipbuilding Fore River Shipyard New York Naval Shipyard Philadelphia Naval Shipyard Norfolk Naval Shipyard |
Operators: | United States Navy |
Preceded by: | Yorktown-class aircraft carrier |
Succeeded by: | Midway-class aircraft carrier |
Built: | 1941 – 1950 |
In commission: | 1942 – 1991 |
Planned: | 32, 26 laid down |
Completed: | 24 |
Cancelled: | 8 |
Preserved: | Intrepid, Hornet, Yorktown, Lexington |
General characteristics | |
Type: | Aircraft carrier |
Displacement: | 27,200 long tons (27,600 t) 36,380 tons full load |
Length: | 872 ft (266 m) |
Beam: | 93 ft (28 m) |
Draught: | 23 ft (7.0 m) |
Propulsion: | Westinghouse geared turbines connected to 4 shafts; 8 Babcock & Wilcox boilers |
Speed: | 33 knots (61 km/h) |
Range: | 15,000 nmi. at 15 knots (28,000 km at 28 km/h) |
Armament: |
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Armor: | 1.5 in (38 mm) hangar deck, 2.5 to 4 in (64 to 102 mm) belt |
Aircraft carried: | 90–100 (Lexington 110 aircraft) |
Essex was a class of aircraft carriers of the United States Navy, which constituted the 20th century's most numerous class of heavy warships, with 24 ships built in both "short-hull" and "long-hull" versions. Thirty-two were originally ordered, however six were canceled before construction, and two were canceled after construction had begun. The Essex-class carriers were the backbone of the Navy's combat strength during World War II, and along with the addition of the three Midway-class carriers just after the war continued to be until the supercarriers began to come into the fleet in numbers during the 1960s and 1970s.
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The preceding Yorktowns formed the basis from which the Essex class was developed. Designed to carry a larger air group, and unencumbered by pre-war naval treaty limits, Essex was over sixty feet longer, nearly ten feet wider in beam, and more than a third heavier. A longer, wider flight deck and a deck-edge elevator facilitated more efficient aviation operations, enhancing the ship's offensive and defensive air power. Machinery arrangement and armor protection was greatly improved from previous designs. These features, plus the provision of more anti-aircraft guns, gave the ships much enhanced survivability. In fact, none of the Essex-class carriers were lost and two, Franklin and Bunker Hill, came home under their own power even after receiving heavy damage and were successfully repaired.
U.S. carriers had the same amount of deck armor as their British counterparts. While debates raged, and continue to this day, regarding the effect of strength deck location (flight deck level on British ships vs. hangar deck level on American ships), British designers' comments tended to disparage the use of deck armor, but some historians, such as D.K. Brown in Nelson to Vanguard, see the American arrangement to have been superior, until the larger size of the first supercarriers necessitated a deeper hull, and thus moving the strength deck to the flight deck. Locating the strength deck at hangar deck level in the Essex-class ships reduced the weight located high in the ship, resulting in smaller supporting structures and more aircraft capacity for the desired displacement.[1]
After the abrogation of disarmament treaties by Japan in 1936, the U.S. took a realistic look at its naval strength. With the Naval Expansion Act of Congress passed on 17 May 1938, an increase of 40,000 tons in aircraft carriers was authorized. This permitted the building of Hornet and Essex, which became the lead ship of her class.
CV-9 was to be the prototype of the 27,000-ton (standard displacement) aircraft carrier, considerably larger than Enterprise, yet smaller than Saratoga (a battlecruiser converted to a carrier). These were to become known as Essex-class carriers, although this classification was later dropped in the 1950s. On 9 September 1940, eight more of these carriers were ordered: Hornet, Franklin, Ticonderoga, Randolph, Lexington, Bunker Hill, Wasp, and Hancock. The last two of the 13 originally programmed CV-9 class aircraft carriers, Bennington and Boxer, were ordered on 15 December 1941.
Lexington, Wasp, Hornet, and Yorktown were renamed during construction, in keeping with the Navy's intent to carry on the traditions of their fighting predecessors, sunk in combat in 1942. Of the original 13 ordered Essex-class ships, four (Ticonderoga, Randolph, Hancock, and Boxer) were modified during construction as part of the "long hull" group, with the bow extended into a "clipper" shape to provide room for additional anti-aircraft armament.
Nineteen more Essexes were ordered or scheduled, starting with ten on 7 August 1942. Only two, Bon Homme Richard and Oriskany were laid down as Essex "short hull" ships. The remainder became Ticonderoga-class or "long hull" ships.
Lexington was originally laid down as Cabot, but was renamed during construction after the original Lexington was lost in the Battle of the Coral Sea in May 1942; she was commissioned on 17 February 1943. Yorktown, originally to be named Bon Homme Richard, was renamed after the original Yorktown was lost at the Battle of Midway on 7 June 1942. Wasp's name was changed from Oriskany after the original Wasp was sunk in September 1942 in the South Pacific while escorting a troop convoy to Guadalcanal, and Hornet's name was changed from Kearsarge after the original Hornet was lost in October 1942 in the Battle of Santa Cruz Islands. The names of the Ticonderoga and the Hancock were swapped while they were under construction. The John Hancock life insurance company had offered to conduct a bond drive to raise money for the Hancock if that name was used for the carrier under construction in the company’s home state of Massachusetts.[2]
In summary, during World War II and until its conclusion, the US Navy ordered 32 aircraft carriers of the Essex and Ticonderoga classes, of which 26 were laid down and 24 actually commissioned.
In drawing up the preliminary design for Essex, particular attention was directed at the size of both her flight and hangar decks. Aircraft design had come a long way from the comparatively light planes used in carriers during the 1930s. Flight decks now required more takeoff space for the heavier aircraft being developed. Most of the first-line carriers of the pre-war years were equipped with flush deck catapults, but owing to the speed and size of these ships very little catapulting was done except for experimental purposes.
With the advent of war, airplane weights began to go up as armor and armament got heavier; aircrew complements also increased. By the war's end in 1945, catapult launches would become more common under these circumstances, with some carrier commanding officers reporting up to 40% of launches by catapult.
The hangar area design came in for many design conferences between the naval bureaus. Not only were the supporting structures to the flight deck required to carry the increased weight of landing and parked aircraft, but they were to have sufficient strength to support the storing of spare fuselages and parts (50% of each plane type aboard) under the flight deck and still provide adequate working space for the men using the area below.
One innovation in Essex was a portside deck-edge elevator in addition to two inboard elevators. The deck-edge elevator was adopted in the design after it proved successful on the Wasp.[3] Experiments had also been made with hauling aircraft by crane up a ramp between the hangar and flight decks, but this method proved too slow. The Navy's Bureau of Ships and the Chief Engineer of A.B.C. Elevator Co. designed the engine for the side elevator. It was a standard elevator, 60 by 34 ft (18 by 10 m) in platform surface, which traveled vertically on the port side of the ship. The design was a huge success which greatly improved flight deck operations.
There would be no large hole in the flight deck when the elevator was in the "down" position, a critical factor if the elevator ever became inoperable during combat operations. Its new position made it easier to continue normal operations on deck, irrespective of the position of the elevator. The elevator also increased the effective deck space when it was in the "up" position by providing additional parking room outside the normal contours of the flight deck, and increased the effective area on the hangar deck by the absence of elevator pits. In addition, its machinery was less complex than the two inboard elevators, requiring about 20% fewer man-hours of maintenance.
Ongoing improvements to the class were made, particularly with regards to the ventilation system, lighting systems, and the trash burner design and implementation.
These carriers had better protecting armor than their predecessors, better facilities for handling ammunition, safer and greater fueling capacity, and more effective damage control equipment. Yet, these ships were also designed to limit weight and the complexity of construction, for instance incorporating extensive use of flat and straight metal pieces.[4]
The original design for the class assumed a complement of 215 officers and 2,171 enlisted men. However, by the end of World War II most crews were 50% larger than that.[5]
The tactical employment of U.S. carriers changed as the war progressed. In early operations, through 1942, the doctrine was to operate singly or in pairs, joining together for the offense and separating when on the defense—the theory being that a separation of carriers under attack not only provided a protective screen for each but also dispersed the targets and divided the enemy's attack. Combat experience in those early operations did not bear out the theory, and new proposals for tactical deployment were the subject of much discussion.
As the new Essex- and Independence-class carriers became available, tactics changed. Experience taught the wisdom of combined strength. Under attack, the combined anti-aircraft fire of a task group's carriers and their screen provided a more effective umbrella of protection against marauding enemy aircraft than was possible when the carriers separated.
When two or more of these task groups supported each other, they constituted a fast carrier task force. Lessons learned from operating the carriers as a single group of six, as two groups of three, and three groups of two, provided the basis for many tactics which later characterized carrier task force operations, with the evolution of the fast carrier task force and its successful employment in future operations.
The pride of the carrier, known as the "Sunday Punch", was the offensive power of 36 fighters, 36 dive bombers and 18 torpedo planes. The F6F Hellcat would be the standard fighter, the SB2C-1 Helldiver the standard scout aircraft and dive-bomber, and the TBF Avenger was designed as a torpedo plane but often used in other attack roles. Some late Essexes, such as Bunker Hill, also included squadrons of F4U Corsairs in fighter-bomber squadrons (VBFs), the precursor to modern fighter-attack squadrons (VFAs).
The defensive plan was to use radio and radar in a combined effort to concentrate anti-aircraft fire.
The design boasted twelve 5 in (127 mm)/38 caliber gun turrets (4 twin turrets located near the island on the starboard side and 4 single turrets located on the port side forward and port side aft), seventeen quadruple 40mm Bofors 40 mm anti-aircraft guns and 65 single 20 mm Oerlikon close-in defense guns. With a range of ten miles and a rate of fire of fifteen rounds per minute, the 5-inch guns fired the deadly VT shells. The VT shells, known as proximity fuzed-shells, would detonate when they came within 70 feet (21 m) of an enemy aircraft. The 5-inch guns could also aim into the water, creating waterspouts which could bring down low flying aircraft such as torpedo planes. The Bofors 40 mm guns were a significant improvement over the 1.1 in/75 caliber guns mounted in the earlier Lexington and Yorktown classes.
The Essex class also made use of advanced technological and communications equipment. The Mark 4 sweeping radar was installed but could not track incoming low-level intruders and was quickly replaced with the improved Mark 12. A Plan Position Indicator (PPI) display was used to keep track of ships and enabled a multi-carrier force to maintain a high-speed formation at night or in foul weather. The new navigational tool known as the Dead Reckoning Tracer was also implemented for navigation and tracking of surface ships. Identification Friend or Foe (IFF) was used to identify hostile ships and aircraft, especially at night or in adverse weather. The four-channel Very High Frequency (VHF) radio permitted channel variation in an effort to prevent enemy interception of transmissions. It also allowed for simultaneous radio contact with other ships and planes in the task force.
Modifications were made throughout the Essex building program. The number of 20mm and 40mm anti-aircraft guns was greatly increased, new and improved radars were added, the original hangar deck catapult was removed, the ventilation system was substantially revised, details of protection were altered, and hundreds of other large and small changes were executed. In fact, to the skilled observer, no two ships of the class looked exactly the same.
Beginning in March 1943, one visually very significant change was authorized for ships then in the early stages of construction. This involved lengthening the bow into a "clipper" form. The increased rake and flare provided deck space for two quadruple 40mm mounts. Waterline length remained unchanged.[6] Thirteen ships were completed to this design, four in 1944. The rest entered commission between early 1945 and late 1946. These ships have been variously referred to as the "long-bow units",[7][8] the "long-hull group",[9][10] or the "Ticonderoga class".[11][12] However, the U.S. Navy never held any institutional difference between the long-hull and short-hull Essex ships, and postwar refits and upgrades were applied to both groups equally.[11]
The large numbers of new ships, coupled with their larger Midway-class contemporaries, sustained the Navy's air power through the rest of the 1940s, the Korean War era, and beyond. While the spacious hangars accommodated the introduction of jets, various modifications significantly improved the capability of the ships to handle the jets’ increased weight and speed. These modifications included an angled flight deck (a British innovation); jet-blast deflectors (JBDs); greater aviation fuel capacity; and stronger decks, elevators, and catapults.[13]
Five of the long-hulls were laid up in 1946–47, along with all of the short-hulls. Eight stayed on active duty to form, with three Midways, the backbone of the post-war Navy's combat strength. Though the Truman administration's defense economies sent three of the active Essexes into "mothballs" in 1949, these soon came back into commission after the Korean War began. Ultimately, all thirteen had active Cold War service.
Oriskany was completed to an improved design in September 1950, and eight earlier ships were thoroughly rebuilt to the improved Oriskany 27A design under the SCB-27 program in the early 1950s.[14] Six more of the earlier ships were rebuilt to an improved 27C design as the last stage of the SBC-27 program. Antietam received an experimental 10.5 degree angled deck in 1952.[14] An improved angled flight deck became a distinctive feature of the SCB-125 program, and was applied concurrently with the last three 27C conversions and later to all 27A and 27C ships except Lake Champlain.[14] Oriskany got a combined SCB-27 and SCB-125 refit.[14] Shangri-La became the first operational United States angled deck aircraft carrier in 1955.[14]
Korean War and subsequent Cold War needs ensured twenty-two of the twenty-four ships had extensive post-World War II service, all initially with attack air groups. By 1955, seven unconverted Essexes were operating under the anti-submarine warfare carrier (CVS) designation established in August 1953.[14] As the Forrestal-class "supercarriers" entered the fleet, seven 27A conversions were designated CVS to replace the original unconverted ships.[14] Six of the 27As received specialized CVS modifications, including bow-mounted SQS-23 sonar.[14] Two 27C conversions were designated CVS in 1962 and two more in 1969.[14] Unmodernized ships began to leave active service in the late 1950s. The updated units remained active until age and the growing number of supercarriers made them obsolete, from the late 1960s into the middle 1970s. However, one of the very first of the type, Lexington, served until 1991 as a training ship.
Of the six unmodernized long-hull Essexes, three decommissioned in the late 1950s and early 1960s and were promptly reclassified as aircraft transports (AVT), reflecting their very limited ability to safely operate modern aircraft. Boxer, Princeton, and Valley Forge were redesignated Landing Platform Helicopter (LPH) amphibious assault ships for the Marine Corps, and remained in commission with their original straight decks until about 1970.[14] The two least-modernized units went into reserve in the mid-1960s, and the rest passed out of the active fleet between 1969 and 1976. All were scrapped, most in the 1970s, although Shangri-La survived until the late 1980s.
An unmodernised Essex was offered to the Royal Australian Navy in 1960 as a replacement for HMAS Melbourne but the offer was declined due to the expense of modifications required to make it operationally compatible with the RAN's primarily British-designed fleet.[15]
For a typical attack carrier configuration in 1956–57 aboard Bennington, the air wing consisted of one squadron each of the following: FJ3 Fury, F2H Banshees, F9F Cougars, AD-6, AD-5N, and AD-5W Skyraiders, AJ2 Savages, and F9F-8P photo Cougars.[16]
By the mid to late 1960s, the attack air wing had evolved. Oriskany deployed with two squadrons of F-8J Crusaders, three squadrons of A-4E Skyhawks, E-1 Tracers, EKA-3B Skywarriors, and RF-8G photo Crusaders. In 1970, the three A-4 squadrons were replaced by two squadrons of A-7A Corsair IIs.[17] The F-4 Phantom II was considered too heavy to operate from Essexes.
Tasked and fitted out as an ASW carrier, the air wing of an Essex such as Bennington in the 1960s consisted of two squadrons of S-2F Trackers and one squadron of Sikorsky SH-34 ASW helicopters (replaced in 1964 by SH-3A Sea Kings). Airborne early warning was first provided by modified EA-1Es; these were upgraded in 1965 to E-1s. A squadron of A-4Bs were also embarked to provide daylight fighter protection for the ASW aircraft.[16][18]
LPH-converted ships flew only helicopters such as the UH-34 and CH-46 Sea Knight. The LPHs were sometimes also used as aircraft ferries for all branches of the U.S. armed forces. The AV-8A arrived into Marine Corps inventory too late to see regular fixed wing operations return to these ships. It was possible to launch and recover small aircraft like the OV-10 Bronco without need of catapult or arresting wires, but this was very rarely permitted on these straight-deck ships for safety reasons and to avoid interruption of helicopter operations.
One author called the Essex class "the most significant class of warships in American naval history", citing the large number produced and "their role in making the aircraft carrier the backbone of the U.S. Navy."[19]
Essex-class ships played a central role in the Pacific Ocean theater of World War II from 1943 through the end of the war, beginning with raids in the central Pacific and the invasion of Tarawa in the Gilbert Islands. The ships successfully performed a number of missions, included air superiority, attacking the Japanese fleet, supporting landings, fleet protection, bombing the Japanese home islands, and transporting aircraft and troops. Along the way, the carriers survived bombs, torpedoes, kamikazes, and typhoons without one ship being sunk.
Eleven of the Essex carriers participated in the Korean War.[20] These ships played a major role throughout the entire war. Missions included attacks on all types of ground targets, air superiority, and antisubmarine patrols.
Thirteen of the 24 carriers originally built participated in the Vietnam War, including the prelude and follow-up.[20] However, their inability to support the latest aircraft constrained some of those ships to specialized roles as helicopter carriers or antisubmarine platforms. The ships still performing an attack mission generally carried older aircraft types than the supercarriers. Yet, the Essex class still made significant contributions to all aspects of the U.S. war effort. In one notable event, during the Gulf of Tonkin Incident, aircraft from the Ticonderoga fired at North Vietnamese torpedo boats that had attacked a U.S. destroyer.[21]
The carriers also contributed between the wars, projecting U.S. power around the world and performing antisubmarine patrols. When the Cold War heated up, the Essex carriers were often involved, including Quemoy and the Matsu Islands, the Bay of Pigs Invasion, and the Cuban Missile Crisis.[22] Also, from 1957 through 1991 an Essex-class ship served as the Navy's training carrier—the Antietam from 1957 through 1962 and the Lexington for the remainder of the time.[23]
Several Essex-class ships played a part in the United States' human spaceflight program, as recovery ships for unmanned and manned spaceflights, between 1960 and 1973.
Valley Forge was the recovery ship for the unmanned flight of Mercury-Redstone 1A on 19 December 1960. The first spaceflight by an American was on Mercury-Redstone 3, recovered by Lake Champlain on 5 May 1961. Randolph recovered the next flight, Mercury-Redstone 4, on 21 July 1961, and she was the primary recovery ship for Mercury-Atlas 6. The next manned flight, Mercury-Atlas 7, was picked up by Intrepid on 24 May 1962, and Kearsarge recovered the last two Mercury spacecraft, Mercury-Atlas 8, on 3 October 1962, and Mercury-Atlas 9, on 16 May 1963.[24]
When the Mercury program's successor, Project Gemini, got underway, Essexes were again closely involved. Lake Champlain recovered the second unmanned flight, Gemini 2, on 19 January 1965; and Intrepid recovered the first manned flight, Gemini 3. Wasp recovered the crew of Gemini IV on 7 June, and on 29 August, Lake Champlain picked up Gemini 5 after eight days in space. In December 1965, Wasp made history by picking up two spacecraft in just over two days: Gemini VI-A on 16 December, and Gemini 7 on 18 December, after their orbital rendezvous test flight. She also recovered Gemini 9A on 6 June 1966 and the final Gemini spaceflight, Gemini 12 on 15 November.[25]
The successful use of the carriers as recovery ships continued into the Apollo program. On 26 February 1966, Boxer recovered the command module from AS-201, the first unmanned flight of a production Apollo Command and Service Module. AS-202, another sub-orbital test flight of the command module, was recovered in August by Hornet; the command module from that flight is currently on display aboard Hornet. Bennington recovered the command module of Apollo 4, the first unmanned flight of the Saturn V launch vehicle, on 9 November 1967.[26]
Eleven months later, Essex recovered the astronauts of Apollo 7, the first manned mission in the Apollo program, after eleven days in orbit. Yorktown recovered the astronauts of Apollo 8, after their historic flight around the Moon in December 1968; and Princeton recovered the second crew to orbit the Moon, aboard Apollo 10, in May 1969.[26]
Hornet rejoined the program and recovered the astronauts from the first two moon landing missions, Apollo 11 in July 1969[26] and Apollo 12 in November.[27] The first steps on Earth of returning astronauts Neil Armstrong, Edwin Aldrin, and Mike Collins, are marked on her hangar deck, as part of her Apollo program exhibit. The three subsequent missions utilized amphibious assault ships as support vessels;however, Ticonderoga recovered the astronauts of the last two moon missions, Apollo 16[28] and Apollo 17 in April and December 1972.[29]
In the post-Apollo era, Ticonderoga again acted as a recovery ship for the astronauts of Skylab 2, the first manned mission to Skylab, the first U.S. orbital space station, in June 1973.[30]
Four Essex-class ships have been preserved, and opened to the public as museums:
Until Midway opened at San Diego, every preserved aircraft carrier in the U.S. was an Essex.
Oriskany was sunk in 2006 to form an artificial reef off the coast of Pensacola, Florida.
Ship | Keel laid | Launched | Commissioned | Decommissioned | Fate |
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USS Essex (CV-9) | April 1941 | July 1942 | December 1942 | June 1969 | Scrapped (June 1975) |
USS Yorktown (CV-10) | December 1941 | January 1943 | April 1943 | June 1970 | Museum (October 1975) |
USS Intrepid (CV-11) | December 1941 | April 1943 | August 1943 | March 1974 | Museum (August 1982) |
USS Hornet (CV-12) | August 1942 | August 1943 | November 1943 | June 1970 | Museum (July 1989) |
USS Franklin (CV-13) | December 1942 | October 1943 | January 1944 | February 1947 | Scrapped (August 1966) |
USS Ticonderoga (CV-14) | February 1943 | February 1944 | May 1944 | September 1973 | Scrapped (September 1975) |
USS Randolph (CV-15) | May 1943 | June 1944 | October 1944 | February 1969 | Scrapped (May 1975) |
USS Lexington (CV-16) | July 1941 | September 1942 | February 1943 | November 1991 | Museum (June 1992) |
USS Bunker Hill (CV-17) | September 1941 | December 1942 | May 1943 | January 1947 | Scrapped (May 1973) |
USS Wasp (CV-18) | March 1942 | August 1943 | November 1943 | July 1972 | Scrapped (May 1973) |
USS Hancock (CV-19) | January 1943 | January 1944 | April 1944 | January 1976 | Scrapped (September 1976) |
USS Bennington (CV-20) | December 1942 | February 1944 | August 1944 | January 1970 | Scrapped (January 1994) |
USS Boxer (CV-21) | September 1943 | December 1944 | April 1945 | December 1969 | Scrapped (February 1971) |
USS Bon Homme Richard (CV-31) | February 1943 | April 1944 | November 1944 | July 1971 | Scrapped (March 1992) |
USS Leyte (CV-32) | February 1944 | August 1945 | April 1946 | May 1959 | Scrapped (March 1970) |
USS Kearsarge (CV-33) | March 1944 | May 1945 | March 1946 | February 1970 | Scrapped (September 1970) |
USS Oriskany (CV-34) | May 1944 | October 1945 | September 1950 | September 1976 | Scuttled as an artificial reef (May 2006) |
USS Antietam (CV-36) | March 1943 | August 1944 | January 1945 | May 1963 | Scrapped (February 1974) |
USS Princeton (CV-37) | September 1943 | July 1945 | November 1945 | January 1970 | Scrapped (May 1971) |
USS Shangri-La (CV-38) | January 1943 | February 1944 | September 1944 | July 1971 | Scrapped (August 1988) |
USS Lake Champlain (CV-39) | March 1943 | November 1944 | June 1945 | May 1966 | Scrapped (April 1972) |
USS Tarawa (CV-40) | March 1943 | May 1945 | November 1945 | June 1967 | Scrapped (October 1968) |
USS Valley Forge (CV-45) | September 1944 | November 1945 | November 1946 | January 1970 | Scrapped (October 1971) |
USS Philippine Sea (CV-47) | August 1944 | September 1945 | May 1946 | December 1958 | Scrapped (March 1971) |
Oriskany (CV-34) was ordered and laid down as an Essex-class vessel, was completed in 1950 to the much modified SCB-27A design.
Reprisal (CV-35), laid down in July 1944 at the New York Navy Yard and launched in 1945, was scrapped incomplete after tests; and Iwo Jima (CV-46) was laid down at Newport News Shipbuilding yards in January 1945 but cancelled in August 1945 and broken up on the slipway.
Six fiscal-year 1945 ships, none of which received names, were assigned to Bethlehem Steel Company (CV-50), New York Navy Yard (CVs 51 & 52), Philadelphia Navy Yard (CV-53) and Norfolk Navy Yard (CVs 54 and 55). Their construction was cancelled in March 1945.
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