Two 18 Inch Gun Battleships

The IJN Yamato was not the only battleship to have wielded 18 inch guns, nor was Japan the first nation to develop such a large navy gun.  The 18 inch "gun size" milestone really belongs to the Royal Navy, which in 1917 commissioned HMS Furious.

HMS Furious was originally designed to carry two eighteen inch guns: with one barrel in each turret.  Unfortunately, she was too "light" a vessel to cope with the stresses that were generated when the guns were fired, and as such, was soon converted into an aircraft carrier.

Twenty four years later, the Japanese were also to learn important lessons about the firing of 18 inch guns, when IJN Yamato was completed.  In this case, each turret featured three 18.1 inch gun barrels, and it was found that the "blast effects" were very extreme when they were fired.  Now, although Yamato was "heavy" enough to cope with these stresses, exposed personnel certainly were not!  This meant that deck-mounted anti-aircraft guns had to be shielded.