Editing Formidable-class battleship (section)

{{Short description|Pre-dreadnought battleship class of the British Royal Navy}}
{{good article}}
{{Use shortened footnotes|date=October 2022}}
{{Use dmy dates|date=January 2017}}
{{Use British English|date=January 2017}}
{|{{Infobox ship begin |infobox caption=''Formidable''-class battleship}}
{{Infobox ship image
|Ship image=HMS Implacable Spithead 1909 Flickr 4793355702 4792e59389 o.jpg
|Ship caption=HMS ''Implacable'' at [[Spithead]] in 1909.
}}
{{Infobox ship class overview
|Name=''Formidable''-class battleship
|Builders=
|Operators={{navy|United Kingdom}}
|Class before={{sclass|Canopus|battleship|4}}
|Class after={{sclass|London|battleship|4}}
|Built range=1898–1901
|In commission range=1901–1919
|Total ships completed=3
|Total ships lost=2
|Total ships retired=1
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=
|Ship class=[[Pre-dreadnought battleship]]
|Ship displacement=
*[[Normal displacement|Normal]]: {{convert|14480|to|14720|LT|abbr=on|lk=on}}
*[[Full load]]: {{convert|15805|to|15930|LT|abbr=on}}
|Ship length={{convert|431|ft|9|in|m|abbr=on|1}} [[Length overall|o/a]]
|Ship beam={{convert|75|ft|m|abbr=on|1}}
|Ship draught=
*{{convert|26|ft|abbr=on|0}} (normal)
*{{convert|28|ft|8|in|abbr=on|0}} (loaded)
|Ship power=
*20 × [[water-tube boiler]]s
*{{convert|15000|ihp|kW|lk=in|abbr=on}}
|Ship propulsion=
* 2 × [[triple-expansion steam engine]]s
* 2 × [[screw propeller]]s
|Ship speed={{convert|18|kn|lk=in}}
|Ship range={{convert|5100|nmi|lk=in|abbr=on}} at {{convert|10|kn}}
|Ship capacity=
|Ship complement=788
|Ship armament=
*4 × [[BL 12 inch Mk IX naval gun|BL 12-inch (305-mm) Mk IX gun]]s
*12 × [[BL 6 inch Mk VII naval gun|BL {{convert|6|in|mm|abbr=on|0}} Mk VII gun]]s
*10 × [[QF 12 pounder 12 cwt naval gun|QF 12-pounder gun]]s
*6 × [[QF 3 pounder Hotchkiss|QF 3-pounder gun]]s
*4 × [[British 18 inch torpedo|{{cvt|18|in|0}}]] submerged [[torpedo tube]]s
|Ship armour=
*[[Belt armor|Belt]]: {{convert|9|in|mm|abbr=on|0}}
*[[Bulkhead (partition)|Bulkhead]]s: {{convert|9|-|12|in|mm|abbr=on|0}}
*[[Barbette]]s: {{convert|12|in|mm|abbr=on|0}}
*[[Gun turret|Turret]]s: {{convert|10|in|mm|abbr=on|0}}
*[[Casemate]]s: {{convert|6|in|mm|abbr=on|0}}
*[[Conning tower]]: {{convert|14|in|mm|abbr=on|0}}
*[[Deck (ship)|Deck]]: {{convert|1|-|3|in|mm|abbr=on|0}}
|Ship notes=
}}
|}

The '''''Formidable'' class''' of [[battleship]]s were a three-ship class of [[pre-dreadnought]]s designed by [[William Henry White|Sir William White]] and built for the [[Royal Navy]] in the late 1890s. The class comprised {{HMS|Formidable|1898|2}}, {{HMS|Irresistible|1898|2}}, and {{HMS|Implacable|1899|2}}. They were armed with a battery of four {{convert|12|in|adj=on|0}} guns, they had top speed of {{convert|18|kn}}, and they marked the adoption of [[Krupp armour]] in British battleship designs. The class formed the basis for the nearly identical {{sclass|London|battleship|4}} of five ships, and those ships are sometimes included in the ''Formidable'' class. ''Formidable'', ''Irresistible'', and ''Implacable'' were built between 1898 and 1901 at the [[Portsmouth Dockyard|Portsmouth]], [[Chatham Dockyard|Chatham]], and [[HMNB Devonport|Devonport Dockyards]], respectively.

All three ships served in the [[Mediterranean Fleet]] early in their careers, before returning to British waters in the late 1900s for duty in the [[Home Fleet]], [[Channel Fleet]], and the [[Atlantic Fleet (United Kingdom)|Atlantic Fleet]]. By 1912, all three ships had been assigned to the [[5th Battle Squadron]], Home Fleet, where they remained until the outbreak of the [[First World War]] in August 1914. They patrolled the [[English Channel]] in the early months of the war and escorted troopships carrying elements of the [[British Expeditionary Force (World War I)|British Expeditionary Force]] and other [[British Army]] units across the Channel to France. On the night of 31 December 1914 – 1 January 1915 while on patrol in the Channel, the 5th Squadron encountered a German [[U-boat]] that torpedoed and sank ''Formidable''. ''Irresistible'' was sent to the [[Dardanelles Campaign]] in February 1915, and after engaging in a series of attacks on the Ottoman coastal fortifications, she struck a [[naval mine]] and sank.

''Implacable'', the sole surviving member of the class, joined the Dardanelles operations in March 1915 and saw action during the [[Landing at Cape Helles|landings at Cape Helles]] in April. She was later withdrawn, first in May 1915 to reinforce the Italian fleet guarding the [[Adriatic Sea]] and then to [[Salonika]] in November that year. After being recalled to Britain in July 1917, she was converted into a [[depot ship]] and used to support the [[Northern Patrol]]. After the war, she was sold for [[scrap]] in 1921 and was [[broken up]] in 1922.