Colossus class battleship (1910)

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The Colossus class of two battleships of the British Royal Navy were among the first dreadnoughts following the original HMS Dreadnought of 1906. Originally intended to be part of the Neptune class, the two ships had thicker armour and other differences from Neptune, and so Neptune is traditionally left as its own class. They were the last 12 inch gunned dreadnought battleships for the Royal Navy, and were followed by the first "super-dreadnoughts", the Orion class battleships with 13.5 inch guns.

[edit] Design

In designing this class, their Lordships of the Admiralty finally took note of the vulnerability of British capital ships in view of the general move to 12 inch guns by the German navy. Thus the main belt reverted to the 11 inch thickness of Dreadnought, with the unfortunate corollary of necessitating a reduction in internal protection to compensate. The design was also influenced by the American Delaware class battleship's ability to mount a ten-gun broadside. To save 50 tons of topweight, the mainmast was suppressed. Besides the weight, the mainmast was considered to be of limited value. Meanwhile Dreadnoughts flaw in that the foremast was just behind the fore funnel was inexplicably repeated. In the Colossus class, this situation was aggravated by the far larger power of the boler installation served by the funnel.

Machinery was for the first time divided into three compartments instead of two. This was thought to provide resistance to flooding to balance the loss of screening bulkheads. Machinery was otherwise identical to that fitted previously, except apparently the new internal arrangements allowed the center engine room to operate independently during cruising conditions to conserve fuel.

Main armament remained the same as the Neptune class battleships, except the stagger of the wing turrets was reduced to conserve deck space. This enabled the forward superstructure to be lengthened and the distribution of the secondary armament to be improved.

[edit] General characteristics

Length: 546 ft (166.4 m)
Beam: 85 ft (25.9 m)
Draught: 26.3 ft (8 m)
Displacement
- Normal: 19,680 tons
- Fully laden: 22,700 tons
Propulsion: Steam turbines with 25,000 shp and four shafts
Speed: 21 knots
Armament:
- Ten 12 in guns (5 × 2)
- Sixteen 4 in guns (16 × 1)
- 3 × 12-in Torpedo tubes
Armour:
- Belt: 11 in
- Bulkheads: 10 in
- Barbettes: 11 in
- Turret: 11 in
- Deck: 4 in