North Carolina class
| North Carolina- class | |
|---|---|
_underway_at_sea_on_3_June_1946_(NH_97267).jpg) The USS North Carolina (BB-55) 1946 |
|
| Overview | |
| Type | Battleship |
| units |
North Carolina (BB-55) Washington (BB-56) |
| Namesake | State of North Carolina |
| 1. Period of service |
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|
| Technical specifications | |
| displacement |
35,000 ts (standard); |
| length |
221.90 m |
| width |
33.90 m |
| Draft |
9.65 m |
| crew |
between 1,500 and 2,800 |
| drive |
4 propellers, driven by 4 steam turbines; 121,000 shaft horsepower (90 MW ) |
| speed |
27–27.5 kn (50–51 km / h) |
| Range |
5,740 nm (10,630 km) at 25 kn |
| Armament |
1941
1945
|
| Aircraft | |
The North Carolina-class battleship was a class of two battleships of the US Navy . The North Carolina and Washington were the first American battleships to be built after the Washington Naval Treaty was signed and were the first in a new generation of fast battleships capable of escorting aircraft carriers . Both ships entered service with the Navy a few months before the United States entered World War II and remained in the fleet until 1947. The main area of operation was the Pacific theater of war ; Washington operated in the North Atlantic for a few months in 1942 . The type ship has been preserved as a museum ship since 1962 , its sister ship was scrapped in 1961.
history
prehistory
At the end of the First World War , the US Navy battleship fleet had grown considerably, and several more ships were still under construction at various shipyards. With the conclusion of the Washington Fleet Treaty in 1922, the construction of further ships had to be stopped, so the six battleships of the South Dakota class were demolished on the slipways , four of the six battle cruisers of the Lexington class experienced the same fate, only two of the existing hulls were allowed to be converted into aircraft carriers. In the following years the fleet was modernized only sporadically, no newbuildings were carried out at all, also because the London additional protocol to the fleet contract of 1930 stipulated an age of at least 26 years for ships to be replaced. This would mean that the oldest ships in the US Navy, the battleships Arkansas and New York , would be replaced by new ships in 1938 and 1940 at the earliest.
In addition to being limited by the fleet contracts, which stipulated a maximum displacement of 35,000 ts and a maximum caliber of 35.6 cm, there was a dispute with the growing air force about the tight finances in times of the global economic crisis . It was only under President Roosevelt in 1933 that the Navy received the financial means it needed to begin the urgently needed modernization of the fleet.
Planning
The Bureau of Construction & Repair had already examined various designs for new battleships in the 1920s. An arrangement of the heavy artillery as on the ships of the Nelson class was also considered. From 1935, the US Navy demanded a maximum speed of 30 knots for the new battleships so that they could be used with aircraft carrier associations. However, these considerations were abandoned a short time later and a speed of 27 to 28 knots with better armor protection at the same time was required. In the period that followed, various designs were submitted, and British proposals for a battleship with a displacement of only 25,000 ts and 305 mm guns were examined. However, these designs turned out to be too small for the needs of the US Navy. By 1936, 38 different designs had been created, the majority of which included a maximum utilization of the displacement limits of 35,000 ts and 356 mm guns like the British King George V class in three turrets in different arrangements. In November 1936, the naval command decided on a design with 356-mm artillery, after Congress had approved the funds to build the battleships in June . After inquiries to Japan regarding the limitation of the caliber to 356 mm remained unanswered and there was reason to believe that the Japanese used not only 406 mm guns but much larger calibers in their new builds, it was decided on June 21, 1937, to equip the new American battleships with nine 406 mm guns. Three days later it was finally decided to build the two battleships.
construction
The construction contracts for the two North Carolina-class battleships were placed on August 1, 1937, at the two naval shipyards Brooklyn Navy Yard in Brooklyn , New York and the Philadelphia Navy Yard in Philadelphia , Pennsylvania . The keel of the North Carolina was laid on October 27, 1937, the Washington was laid on June 14, 1938. After almost two years of construction, the Washington was launched on June 1, 1940, the North Carolina followed twelve days later. Both ships were put into service by the US Navy in the spring of 1941 after 41 and 35 months respectively. In the manufacture of the ships, the arc welding process was used for the first time on a large scale to reduce weight when connecting the ship segments. The construction costs per ship amounted to about 76 million US dollars .
commitment
Both ships were declared operational in 1942, the Washington was sent in March 1942 to reinforce the British Home Fleet in the North Atlantic, where it accompanied convoys until June. She was then used in the Pacific like her sister ship from September. Both ships took part in almost all operations during the following years, they mostly operated as escort ships for the Fast Carrier Task Force . On the night of November 14-15, the Washington sank the Japanese battleship Kirishima in the Battle of Guadalcanal . The fire control of the heavy artillery, which landed nine direct hits on the Japanese ship, was completely taken over by the radar systems of the Washington .
Damage
_damaged_after_her_1_Feb._1944_collision_with_USS_Indiana_(BB-58).jpg)
The North Carolina was hit by a torpedo from the Japanese submarine I-19 on September 15, 1942 , and the explosion tore a 30 square meter hole in the port side of the battleship. Six crew members of the battleship were killed. Despite the ingress of water and the list, the North Carolina remained operational and, after emergency repairs, was able to sail to Pearl Harbor on its own, where the damage was completely repaired during a stay in the shipyard. She was the only US battleship to be hit by a submarine torpedo during the war.
On February 1, 1944, the Washington collided with the Indiana off Kwajalein . The forecastle was crushed about 20 meters and destroyed, and repairs in the Puget Sound Navy Yard lasted until June.
Whereabouts
After the end of the war, both ships remained in the fleet until June 27, 1947, when they were retired and transferred to the reserve fleet . The Washington was struck from the shipping registers in 1960 and scrapped the following year. The North Carolina became a museum ship two years after being removed from the lists. It is located on the banks of the Cape Fear River in Wilmington , North Carolina .
Modifications
In 1954, based on a request by the Ship Characteristics Board, investigations were made to determine whether the ships would be suitable for fast fleet operations through modifications. The necessary speed of 31 knots would have made it necessary to double the propulsion power. The space required for this should have been covered by expanding the aft gun turret. The installation of gas turbines as boosters was also examined. The extensive changes to the hull and the propulsion system would have resulted in costs of 40 million US dollars per ship. For this reason, these plans were not pursued any further.
Another study, based on the experience the Americans had with the captured fleet supplier Dithmarschen , who was put into service as Conecuh in the Navy, suggested converting the battleships into fast fleet suppliers. Costs of 25 million US dollars per ship and low profitability and efficiency compared to the Conecuh led to the end of the project.
technology
Hull and superstructure
_forward_superstructure,_August_1941.jpg)
The North Carolina-class ships were the first battleships to conform to the new naval architecture of the US Navy. They had a continuous main deck, the so-called "flush deck" and a strengthened bow stem . The ships were 217.46 meters long at the construction waterline, the overall length was 221.90 meters. The width in the KWL was 31.80 meters, the maximum width, limited by the lock chambers of the Panama Canal, was 33.90 meters. The length-to-width ratio of the fuselage was thus 6.82. The design displacement of 36,600 standard tons was above the limit of 35,000 ts set in the fleet contract. The operational displacement including ammunition, fuel and water was a maximum of 44,800 ts. The construction draft was 9.65 meters, the draft at deployment displacement was 10.82 meters.
About a third of the hull was electrically welded. The frame spacing was 1.219 meters, the hull was divided into 21 watertight compartments and six decks . For the first time it had no portholes, which increased safety, but made forced ventilation below deck necessary.
The five-deck three-tower superstructure with the two single chimneys extended over the middle third of the ship's length. The bridge structure was completed by a 15 meter high tower mast , which replaced the "waste paper basket masts" used on the older battleships. He carried the battleship radars and a range finder at the tip.
Armor
_during_construction.jpg)
The core of the armor on the battleships was the deck structure , which was 134 meters long and a maximum of 21 meters wide. It includes vital ship systems such as the propulsion systems and ammunition chambers below deck as well as the command tower in the superstructure. For the first time in the North Carolina class, the rudder system and the shaft tunnel were also armored in order to maintain mobility and maneuverability even under enemy fire.
The maximum thickness of the side armor was 305 mm, it was inclined 15 ° from the vertical in order to deflect steeply falling shells and to increase the armor thickness. The side armor tapered down to 167 mm, below which a 1.6-meter-wide side bulge started to keep the explosive energy of impacting projectiles away from the ship's systems. In the area of the ammunition chambers, another 95 mm thick torpedo bulkhead secured the ammunition supplies as a “citadel in the citadel”. The ship floor was designed as a double floor throughout, and as a triple floor in the area of the citadel. 282 mm thick armored bulkheads closed off the citadel fore and aft.
The torpedo protection from the side armored bulkheads and the chambers in front of it, some of which were used as fuel bunkers, as well as the double and triple floors were intended to intercept torpedo and mine hits with up to 317 kg of explosives without causing damage to vital ship systems.
The main deck was 6 mm thick, 36 mm in the area of the citadel. The main armored deck underneath was reinforced as a fragment catcher to 92 to 108 mm. A third 16 mm thick armored deck was drawn in above the engine rooms, and in the area of the ammunition rooms this was reinforced to 43 mm. The command tower in the superstructure had a maximum of 373 mm thick armor, the ceiling was 178 mm thick. A shaft armored with 356 mm steel connected the command tower with the citadel below deck. The rudder systems aft had a 378 mm thick deck armor, aft they were closed by a 278 mm thick bulkhead. The most massive armor had the barbeds and the front sides of the turrets of the heavy artillery, they were provided with 406 mm armor. The sides of the turrets were 249 mm thick, the backs 300 and the ceilings 178 mm thick.
The total weight of the armor was 15,341 ts, it was supposed to protect the ship against hits from 356 mm shells from a distance of 17 to 27 kilometers. For 406 mm shells, the immunity zone was between 19.2 and 25.3 kilometers in the area of the ammunition chambers and between 21.2 and 23.8 kilometers aft.
Propulsion system
The North Carolina class was the first class of battleship that could reach speeds well over 23 knots. Compared to the previous classes, the ships had a propulsion system four times as powerful.
The number of six steam boilers envisaged in the final draft was increased to eight, which were arranged in pairs in four engine rooms. Two boilers and a turbine set were positioned together in the engine room and formed a separate power plant, but these could be interconnected if required. The turbines alternately drove the shafts on the starboard and port sides. The first diesel generator room was located between the foremost engine room and the ammunition room of the second turret , the second was between the rear turret and the steering gear. In the diesel generator rooms there were evaporator systems that produced the boiler feed water.
_during_construction.jpg)
The boilers were three-drum high-pressure water tube boilers from Babcock & Wilcox . The narrow-tube boilers were oil-fired and had an operating pressure of 40.43 bar and an operating temperature of 454.4 ° C. The steam was about four gear turbine sets of General Electric led. These each consisted of a twelve-stage high - pressure turbine that ran at a maximum of 5904 / min, a six-stage low-pressure turbine with 4537 / min, both for forward travel, and a three-stage reverse turbine with 3299 / min for reverse travel. Each turbine set had an output of 30,250 WPS , the total output of the drive system was 121,000 WPS (90 MW ). The top speed was 27.3 knots , 0.7 knots below the target. The ships had a fuel supply of 7167 tons (North Carolina) and 6583 tons (Washington). This allowed a range of 17,450 nautical miles at 15 knots or 5740 nautical miles at 25 knots. Average fuel consumption was 6.25 tons per hour at 15 knots cruising speed and increased from 27.3 knots to 43.3 tons per hour at top speed.
Four turbo generators, each with an output of 1250 kW, generated the electrical power (450 V ) for the on-board systems. They were supported by four diesel generators with an output of 850 kW each and two auxiliary diesel generators with 200 kW each. The total electrical power was 8400 kW.
Four shafts drove four propellers , the outer shafts inclined slightly outwards from the ship's axis. The propellers were four-bladed fixed pitch propellers, the inner ones had a diameter of 4,674 meters, the outer ones of 5,067 meters. The outer propellers were replaced by three-bladed propellers in 1942 due to strong vibrations. The inner waves ran in so-called keel hooks, which reduced the flow resistance by 5% and at the same time protected the waves from damage. In addition, the outer propellers were offset lengthways by nine meters so that not all propellers would be lost if they were damaged.
Armament
Heavy artillery
_firing_during_the_Second_Naval_Battle_of_Guadalcanal,_14_November_1942.jpg)
Main armament of the North Carolina-class battleships were nine guns in caliber 16 inch , caliber length 45. The guns were in three triple turrets , two of which are on the foredeck and aft were. The 16 meter long and 12 meter wide turrets had a total weight of 1380 tons and 1414 tons for the elevated second tower. The straightening range was 150 ° on each side, and the tubes could be swiveled upwards by 45 ° vertically. Tower 1 and 3 could also pivot the pipes down by 2 °. The lateral directional speed was 4 ° per second, the elevation speed was 12 ° per second. The operating team consisted of two officers and 170 men per tower.
Each gun barrel was 18,694 meters long and weighed 97,231 tons. The run had 96 trains , the train length was 15.668 meters. After each shot, the recoil caused the pipes to return 1.2 meters before being braked by the hydraulic pipe return . The barrel was chrome-plated , the chamber volume was 380.1 cubic decimeters. The rate of fire was two rounds per minute and the estimated life of a barrel was 395 rounds.
The guns could fire armor-piercing Mark 8 shells and high-explosive Mark 13 and Mark 14 shells. The armor-piercing shells weighing 1,225 kg left the tube at 700 m / s and had a range of 33,741 meters at a 45 ° cant. At this distance they could penetrate more than 260 mm of side armor or 265 mm of deck armor, at a distance of 4500 meters the shells could penetrate side armor of over 670 mm. The highly explosive, 862 kg heavy grenades of the type Mark 13 and 14 reached a muzzle velocity of 800 m / s and a maximum range of 36,741 meters at 45 ° cant.
Middle artillery
The battleships' central artillery consisted of 20 guns, 5 inch (127 mm) caliber, 38 caliber length, housed in ten Mark 32 twin turrets. There were five towers on each side of the superstructure. Two turrets were located on the level of the main deck, the others one deck higher on the deckhouse.
The gun turrets, which weighed 47 tons, were electrically operated and had a crew of 27 men. The cadence was usually 15 to 20 rounds per minute, well-rehearsed teams achieved up to 30 rounds per minute. When fired, the pipe ran back up to 38 cm before it was hydraulically dampened. Either Mark 49 fragmentation grenades for air defense or armor-piercing Mark 46 grenades were fired. At a distance of 10 km, the 24.5 kg armor-piercing shells, which left the gun barrel at 792 m / s, could penetrate up to 51 mm of hull armor, the maximum range was at 45 ° barrel elevation over 8 nautical miles. The 25 kg anti-aircraft grenades had a muzzle velocity of 762 m / s and a peak height of almost 12 km.
Anti-aircraft armament
_during_Gilbert_Islands_Operation,_December_1943.jpg)
The anti-aircraft armament originally intended for the battleships consisted of 16 28-mm guns, which were housed in four quadruple mounts on both sides of the superstructure. The 28 mm guns achieved a rate of around 100 rounds per minute, and the maximum range was around 4 nautical miles. The quadruple carriage could be rotated 360 ° and swiveled up to 110 ° upwards and 15 ° downwards. These were supplemented by up to 28 12.7 mm machine guns . Since the machine guns were viewed as too light to repel attacking aircraft at the beginning of the war, the ships received the first 20 mm Oerlikon machine guns in individual mounts in December 1941 . The North Carolina received 40 and the Washington 20 guns. In the course of the war, the number of 20-mm guns was increased to 83, they were set up at every free place on the upper deck. Sometimes double mounts were also used. The 20-mm cannons fired between 250 and 320 rounds per minute, the range was about two nautical miles. The summit height was almost 3000 m.
Since the 28 mm guns soon proved to be unreliable, they were replaced by 40 mm Bofors guns with a 70 caliber length from the summer of 1942 . Towards the end of the war there were 60 40 mm guns on board each of the two ships in 15 quadruple mountings, which gave the ships good anti-aircraft capabilities. The 900 gram shells of the 40 mm guns had a peak height of 6,797 meters, the maximum range at 45 ° barrel elevation was 10,180 meters. The cadence was around 120 rounds per minute, depending on the speed of the operating team, the muzzle velocity was 881 meters per second.
Electronics and sensors
_tower_foremast_view.jpg)
North Carolina and Washington were the first battleships to be equipped with radar systems when they were commissioned. First, the CXAM-1 radar, which had a detection range of 70 nautical miles, was mounted on the tower mast. This was supplemented by the SG surface search radar, the parabolic antenna of which was located under the top mast platform of the tower mast. The SG radar had a detection range of up to 40 kilometers for surface targets and 27 kilometers for air targets. From 1943, the CXAM-1 radar was replaced by the improved successor of the SK type. The radar system was able to locate an approaching bomber at an altitude of 3,000 meters over 185 kilometers. In 1944 the successor SK-2 was introduced, which had a 5.2 meter round antenna that improved the lateral detection field. In 1945, the SP radar was also introduced as a reserve system, which had a detection range of up to 130 kilometers against air targets and 64 kilometers against surface targets. The radar system could also be used as a fighter guidance radar.
The three 406 mm turrets had their own 13.5 m range finders for fire control and distance measurement. These were supplemented by two Mark 38 fire control systems on the tower mast and the aft superstructure, which had an 8 m range finder and a Mark 13 radar antenna. The fire control of the middle artillery secured four Mark 37 fire control systems. Two were in front and aft of the superstructure, two on the sides. The systems had a 4.57 m range finder and a Mark 12 radar system and could track aircraft in level flight up to a speed of 400 knots and in a dive up to a speed of 250 knots. Each of the 15 40 mm quadruple flak also had its own Mark 57 fire control device with Mark 34 radar.
Aircraft
The battleships had two pivoting aircraft catapults on the quarterdeck , each 20.67 meters long. The catapults, which could be swiveled through 360 °, were powered by powder charges. Aircraft that had landed on board were taken back on board using a crane at the stern. Three Vought OS2U Kingfisher aircraft were carried on board . Two planes were placed on the catapults, the third was parked on the quarterdeck in front of the gun turret. Plans - as on the cruisers of the Brooklyn class - to use a lower deck hangar failed because of the narrowness in the stern and the lack of deck height.
Additional information
literature
- Siegfried Breyer: Battleships and battle cruisers 1921–1997. International battleship building. Bernard & Graefe, Bonn 2002, ISBN 3-7637-6225-6 .
- Steve Wiper: Warship Pictorial 29: North Carolina Class Battleships. Classic Warships, Tucson 2007, ISBN 0-9745687-8-3 .
Web links
- North Carolina Class at the Naval Historical Center
- North Carolina class at globalsecurity.org (English)
Footnotes
- ^ History of the USS North Carolina in the Dictionary of American Naval Fighting Ships , as of October 2, 2008
- ^ A b Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 255.
- ^ Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 256.
- ↑ Battleship North Carolina, Prewar ( Memento of the original from September 21, 2005 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. As of October 2, 2008
- ^ Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 257.
- ↑ a b c Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 253.
- ^ Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 258.
- ^ A b Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 264.
- ↑ a b c d e Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 259
- ^ A b Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 260.
- ^ A b Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 261.
- ↑ USS Washington BB56 Fuel Consumption ( Memento of the original from September 23, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. As of August 21, 2009
- ↑ Terzibaschitsch: Combat systems of the US Navy. Koehler Verlagsgesellschaft, Hamburg, 2001, ISBN 3-7822-0806-4 . P. 16ff.
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 33f.
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 29f.
- ↑ navweaps.com, 40 mm / 56 (1.57 ″) Mark 1, Mark 2 and M1 , as of October 2, 2008
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 97.
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 99.
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 104.
- ↑ Terzibaschitsch: Combat systems of the US Navy. P. 153.
- ^ Breyer: Battleships and battle cruisers 1921–1997. International battleship building. P. 263.
