Editing Invincible-class battlecruiser (section)

===Protection===
The armour protection given to the ''Invincible''s the waterline [[Belt armor|belt]] measured {{convert|6|in|mm|0}} amidships was only slightly more than half the thickness of {{HMS|Dreadnought|1906|2}}'s {{convert|11|in|mm|0}}. The belt was six inches thick roughly between the fore and aft twelve-inch gun turrets, but was reduced to four inches from the fore turret to the bow and did not extend aft of the rear turret. A six-inch [[bulkhead (partition)|bulkhead]] met the [[barbette]] of X turret to fully enclose the armoured citadel. The gun turrets and barbettes were protected by {{convert|7|in|mm|0|abbr=on}} of armour, except for the turret roofs which used {{convert|3|in|mm|0|abbr=on}} of [[Krupp]] non-cemented armour (KNC). The thickness of the main [[deck (ship)|deck]] was {{convert|1|in|mm|0|abbr=on}} around the base of barbettes and the crown of the base of the rear [[conning tower]]. It was {{convert|2|in|mm|0|abbr=on}} over the crown of the base of the forward conning tower. The lower deck armour was {{convert|1.5|in|mm|0|abbr=on}} on the flat and two inches thick on the slope, except aft of the rear turret where it was increased to {{convert|2.5|in|mm|0|abbr=on}} to protect the steering gear. The front and sides of the forward conning tower were {{convert|10|in|mm|0|abbr=on}} thick while its rear was {{convert|7|in|mm|0|abbr=on}}. The walls of the rear conning tower were six inches thick. The roof and floor of both conning towers were KNC armour 2&nbsp;inches thick while their communication tubes were {{convert|3|in|mm|0|abbr=on}} of KNC. The signal tower immediately aft of the forward conning tower also had three inches of KNC. [[Plain-carbon steel|Mild steel]] [[torpedo bulkhead]]s of 2.5-inch thickness were fitted abreast the [[magazine (artillery)|magazine]]s and shell rooms. [[Krupp cemented armour]] was used throughout, unless otherwise mentioned.<ref>Roberts, pp. 109, 112</ref>