North Carolina class battleship

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Class overview
*USS North Carolina* (BB-55)**
Name:	North Carolina class battleship
Operators:	United States Navy
Preceded by:	South Dakota (1920)-class
Succeeded by:	South Dakota (1939)-class
Completed:	2
Retired:	2
Preserved:	1
General characteristics
Class and type:	Battleship
Displacement:	35,000 tons (standard); 44,800 tons (1942 full load)
Length:	729 ft (222 m)
Beam:	108 ft (33 m)
Draught:	27 ft (8.2 m)
Propulsion:	121,000 shp (90 MW) geared turbines
Range:	5,740 mi (9,240 km) @ 25 knots 16,320 mi (26,260 km) @ 15 knots
Armament:	9 × 16-inch (406 mm) guns 20 × 5 inch guns 16 × 1.1 inch machine guns
Armour:	Belt: 12.0" on 0.75" STS (305 mm on 19 mm), inclined 15 degrees, tapering to 6.6" on 0.75" STS (168 mm on 19 mm) at lower edge Bulkheads: 11.1" to 1.1" (282 mm to 28 mm) Barbettes: centerline forward: 14.7" (373 mm) sides 16.0" (406 mm) centerline aft 11.5" (292 mm) Turrets: face plates 16.0" (406 mm) sides 9.8" (249 mm) back plates 11.8" (300 mm) roof plates 7.0" (178 mm) Decks: Centerline main 1.45" (37 mm) second 1.4" + 3.6" (36 mm + 91 mm) third 0.62" (16 mm) total 7.07" (180 mm) Outboard 1.45" (37 mm) second 1.4" + 4.1" (36 mm + 104 mm) third 0.75" (19 mm) total 7.70" (196 mm)^[1]
Aircraft carried:	OS2U Kingfisher

North Carolina and her sister ship Washington were amongst the first Post-Washington Treaty battleships as well as the first of the US Navy fast battleships (though some treaty restrictions, specifically those imposed by the Second London Naval Treaty, remained in force and in the initial design the displacement of these new ships was not to exceed 35,000 tons [1]). While not as heavily armored as battleships of other nations, the North Carolina class featured a more powerful main battery, strong anti-aircraft armament, and excellent fire control.

1 Design
2 Service
3 Post-War and Succession
4 Armament
5 References
6 External links

[edit] Design

Before this class, the United States Navy favored staying power and fire power over speed. The North Carolina class had a speed of 27 knots (50 km/h) versus the 21 knots (39 km/h) of the pre-treaty Colorado class. The class was completely different from all previous US battleships, and set the pattern for all subsequent vessels (as well as the reconstructions of vessels wrecked at Pearl Harbor). New features included a massive columnar mast replacing the familiar "cage" mast, main armament in two triple turrets forward, one aft, and dual-purpose secondaries along the sides of the superstructure.

The most important advance of the class was one that could not be seen from outside: The integration of the most advanced computer at sea, the Mark I fire control computer. The analog fire control system allowed the ship to maintain a constant fire control solution even when steaming at full speed and performing drastic evasive turns and was far more accurate than the Dreyer or Ford type mechanical computers used during World War I.

Unfortunately, initially the North Carolinas proved prone to severe vibration problems at high speeds and had to be limited to about 24 knots (44.45 km/h) for much of their service lives - at higher speeds the ships vibrated so badly the rangefinders and radar at the top of the mast could shake to pieces. This problem has been variously attributed to the propeller and skeg design and was ultimately solved by replacing the original propellers. Another, more serious, weakness of the class was that it had been designed as a balanced 14" battleship design, being a close contemporary of the Royal Navy's King George V class (though the King George V was more heavily armored). Both classes were designed to carry twelve 14" guns in three quadruple turret mountings.^[2] After Japan withdrew from the Washington Treaty, the North Carolinas were modified to carry and fire 16" guns, as a result its protection was substandard against the 2,240 lb Mark 5 shells that their 16-inch (406 mm) guns were originally designed to fire. This was rectified in the following South Dakota and Iowa classes, though all of their armour schemes were not proof against the new "super-heavy" 2,700 lb Mark 8 shells that they actually used. However, the only US battleship adequately protected against the Mark 8 shells would have been the never built Montana class.

The United States Navy built two North Carolina-class battleships:

[edit] Service

The ships were originally conceived as main battleships, but like their successors, the South Dakota and Iowa classes, they spent most of their operational lives as escorts for the Fast Carrier Task Force.

At the Battle of the Eastern Solomons in 1942, USS North Carolina downed between 7–14 Japanese aircraft. She was later hit by a Japanese submarine-launched torpedo that year; the only US fast battleship to suffer underwater damage.

USS Washington sank the Kirishima' in the Second Naval Battle of Guadalcanal, demonstrating the accuracy of fire control radar in a night fight and the destructive power of the Mark 8 shells, being the only US World War II-era fast battleship to sink an enemy battleship in combat.

[edit] Post-War and Succession

Being valuable, large hulls, they were considered for many conversion projects but ultimately remained in reserve until disposed of in 1960. Washington was discarded after World War II, while North Carolina was converted to a museum ship in her name state.

Only two North Carolina ships were built, as they were succeeded by the better-protected and similarly well-armed South Dakota, and later the faster Iowa-class battleships.

[edit] Armament

9 × 16-inch (406 mm) guns (Mk VI 45 Cal guns, able to handle the same 2,700 lb "super-heavy" AP shells as the Mk VII 50 Cal guns found on the Iowa class, however the Mk VI gun was lighter and had a shorter range)
20 × 5 inch guns
16 × 1.1 inch machine guns

[edit] References

^ Friedman, Norman: U.S. Battleships: An Illustrated Design History
^ USA 14"/50 (35.6 cm) Mark 7, Mark 11 and Mark B, NavWeaps - Naval Weapons, Naval Technology and Naval Reunions, 22 May 2007.