Battleship Anti-Aircraft - Battleship Bulges
Battleships ruled the waves - it had always been that way, it would always be that way ... If not for the rise of the aircraft - with its ability to drop bombs (against a battleship's deck armour) and its ability to launch torpedoes (against a battleship's hull form, propellers and rudder). Battleships were overhauled, with thickened deck armour (to guard against bombs), with hull form bulges (to guard against torpedoes) and with many anti-aircraft guns (to target enemy aircraft). These could come in two varieties. The first: dedicated secondary armament - that was dual purpose, being capable of targeting both air and surface targets. These guns would usually be around 4 to 5 inch calibre. Their shells either exploded at a predetermined altitude, or at a preset proximity from the enemy aircraft (in the later stages of World War Two). The second: dedicated anti-aircraft guns, which could only target aircraft. These guns would usually be around 0.5 inch to 40 mm calibre. They mostly relied upon their rate of fire - to both deter, and 'bring down' enemy aircraft.
Here we can see the details of the midships area of HMS Hood:
Of particular interest are: i) The eight barrelled 2 pounder anti-aircraft pom poms gun. ii) The 4 inch high angle anti-aircraft gun. iii) One of the secondary armament 5.5 inch naval guns (with it's protective shield). iv) The smaller crane derricks, which were helpful for lifting both ammunition, and smaller boats. v) The torpedo look out control towers. Which I believe, would issue just one command: take evasive action! vi) Venting for the boiler rooms (located at the base of the funnels, just under various life rafts). vii) The smokestacks themselves, which vented waste gases and heat, from Hood's boiler rooms. There's an unproven theory, that the shell that sunk HMS Hood, may very well have penetrated one of these, and detonated the oil fuel (inside her boiler rooms).
Here we can see the look out posts for the various crew members of HMS Hood, that were tasked with looking out for enemy aircraft:
Most of these involved some sort of optical sight (such as binoculars), whereby it's operator would locate enemy aircraft, then obtain various measurements (such as bearing and elevation), which in-turn, was fed into several (analogue) fire control computers, which in-turn was relayed to the gun operators (who opened fire). Hood's anti-aircraft guns, were also capable of local control, when (for example) such bridge tower directors had been knocked out.
Some of the stern gun arrangements of HMS Hood:
From left to right we have: the aft-most eight barrelled 2 pounder anti-aircraft pom poms gun, two 4 inch high angle anti-aircraft guns, and one of the fifteen inch naval gun turrets (with it's local control range finder on-top). The anti-aircraft guns, were situated atop the Admiral's Day Cabin, and much pomp and ceremony, is often associated with the wooden handrail ladders, that lead to this area (bottom left). This was particularly true, of Hood's Empire Cruise, where she entertained VIPs (such as Royalty), from around the World.