Secondary armament

For instance, German doctrine, for fighting in the North Sea, held that poor visibility provided a good opportunity for the shorter ranges at which smaller guns would be effective.

Britain later came around to this point of view, although the primary justification for mounting a 6-inch battery (in the Iron Duke class) remained fighting against the increasingly large torpedo boats and destroyers.

France clung to its pre-dreadnought designs, building six Danton-class battleships which had a secondary armament of 9.4-inch weapons in turrets, before finally shifting to dreadnoughts.

Arguing against, it consumed considerable displacement (2000 tons or more), were holes in the side close to the waterline that increased the risk of capsizing, and could not be heavily armoured yet were connected to magazines that threatened the destruction of the ship.

There were also considerable difficulties in bringing secondary weapons into action with the main guns; they too smoked up the range, splashed and obscured their target, and might require maneuvers to open secondary arcs that put the main guns at a disadvantage.

Battle experience showed that capital ships were almost always accompanied by their flotillas, secondary batteries were ineffective against capital ships, but that German battleship secondary batteries were very effective in the Jutland night action against British destroyers.

Now they needed to be multi-purpose weapons, with a high-angle fire capability to engage aircraft, as well as the traditional use against destroyers.

In order to hit a fast-moving air target, a high rate of fire was required, thus secondary guns reverted slightly to the 5-inch from 6-inch size.