Colossus-class battleship (1910)

File:HMS Colossus (Colossus class dreadnought).jpg HMS Colossus
Class overview
Name:	Colossus-class battleship
Preceded by:	Neptune class
Succeeded by:	Orion class
In commission:	1911–1921
Completed:	2
General characteristics
Type:	Post Dreadnought Battleship
Displacement:	Normal: 19,680 tons Fully laden: 22,700 tons
Length:	546 ft (166.4 m)
Beam:	85 ft (25.9 m)
Propulsion:	Parsons direct drive steam turbines, 25.000 shp on four shafts
Speed:	21 knots (39 km/h)
Complement:	755
Armament:	10 × BL 12 inch / 50 cal Mk XII guns (5 × 2) 16 × BL 4 inch Mk VII guns (16 × 1) 3 × 21-inch (533 mm) submerged torpedo tubes
Armour:	Belt: 11 in (280 mm) Bulkheads: 10 in (254 mm) Barbettes: 11 in (279 mm) Turret: 11 in (279 mm) Deck: 4 in (102 mm)

The Colossus class of two battleships - HMS Colossus and HMS Hercules of the British Royal Navy were among the first battleships 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 (305 mm) gunned dreadnought battleships built for the Royal Navy, and were followed by the first "super-dreadnoughts", the Orion-class battleships with 13.5-inch (343 mm) guns.

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 (305 mm) guns by the German navy. Thus the main belt reverted to the 11-inch (280 mm) 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 Dreadnought's major flaw of positioning the foremast just behind the fore funnel was inexplicably repeated. In the Colossus class, this situation was aggravated by the far greater power of the boiler 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 Neptune, except the stagger of the wing turrets was reduced to conserve deck space, allowing the forward superstructure to be lengthened and the layout of the secondary armament to be improved.

References

• Siegfried Breyer: Battleships and Battlecruisers 1905–1970, J.F. Lehmanns Verlag, Munich, 1970.
• Robert Gardiner: Conway’s All the World’s Fighting Ships 1922–1946, Conway Maritime Press London 1980

External sources

• Dreadnought Project Technical material on the weaponry and fire control for the ships