Ajax-class ironclad

Class overview
Builders:	Pembroke Dockyard Chatham Dockyard
Preceded by:	HMS Inflexible
Succeeded by:	Colossus class
Built:	1876–1883
In commission:	1884–1904
Completed:	2
General characteristics
Displacement:	8,510 tons
Length:	300 ft 9 in (91.67 m) o/a 280 ft (85 m) p/p
Beam:	66 ft (20 m)
Draught:	23 ft 6 in (7.16 m)
Propulsion:	Two-shaft Penn inverted compound I.H.P.= 6,000
Speed:	13 kn (24 km/h)
Complement:	345
Armament:	4 × muzzle-loading rifles 2 × BL Mk II guns
Armour:	Citadel: 18 in (460 mm) tapering to 15 in (380 mm) Turret: 16 in (410 mm) faces, 14 in (360 mm) sides Conning tower: 12 in (300 mm) Bulkheads: 16.5 in (420 mm) to 13.5 in (340 mm) Deck: 3 in (76 mm)

The Ajax class of battleships consisted of two ships, HMS Ajax and HMS Agamemnon serving in the Victorian era Royal Navy. They were ironclad ships, armed with turret-mounted main armament.

The Board of Admiralty have a historical tradition of attempting to follow a successful ship with a smaller and cheaper version. This policy, based on financial considerations, has seldom if ever been successful. Just as HMS Warrior was followed by HMS Defence, and as HMS Queen Elizabeth was followed by HMS Revenge, so was HMS Inflexible followed by Ajax and Agamemnon.

These two ships were built to the same concept as Inflexible - a heavily armoured citadel carrying four heavy guns mounted 'en echelon' in turrets to achieve all-round fire - but were required to be of lighter draught, and to displace 3,000 tons less. It was therefore necessary to arm them with guns of 12.5 inch calibre, as against 16 inch in Inflexible, and to accept a maximum speed of nearly two knots less. Also, unlike the Inflexible, these ships were dependent upon the integrity of their unarmoured ends to maintain buoyancy; should the ends have been damaged enough to become waterlogged, the ships would have sunk.

This class were the last ships in the Royal Navy to be armed with muzzle-loading rifles, and the first to carry any form of secondary armament. They were designed from the start not to carry any form of sailing rig.

References

• Oscar Parkes, British Battleships ISBN 0-85052-604-3
• Conway, All the World's Fighting Ships ISBN 0-85177-133-5