Which 20th century battleship featured artillery with a specially reinforced barrel and steam turbine propulsion?
Built-up gun A built-up gun is artillery with a specially reinforced barrel. An inner tube of metal stretches within its elastic limit under the pressure of confined powder gases to transmit stress to outer cylinders that are under tension. Concentric metal cylinders or wire windings are assembled to minimize the weight required to resist the pressure of powder gases pushing a projectile out of the barrel. Built-up construction was the norm for guns mounted aboard 20th century Dreadnoughts and contemporary railway guns, coastal artillery, and siege guns through World War II.
H-class battleship proposals The H class was a series of battleship designs for Nazi Germany's "Kriegsmarine", intended to fulfill the requirements of Plan Z in the late 1930s and early 1940s. The first variation, "H-39," called for six ships to be built, essentially as enlarged "Bismarck"-class battleship s with 40.6 cm guns. The "H-41" design improved the "H-39" ship with still larger main guns, with eight 42 cm weapons. Two subsequent plans, "H-42" and "H-43", increased the main battery yet again, with 48 cm pieces, and the enormous "H-44" design ultimately resulted with 50.8 cm guns. The ships ranged in size from the "H-39", which was 277.8 m long on a displacement of 56444 MT , to the "H-44", at 345 m on a displacement of 131000 MT . Most of the designs had a top speed in excess of 30 kn .