dreadnought

A dreadnought is a battleship design that dominated naval warfare from the early 1900s until jet aircraft changed the game. The original HMS Dreadnought, launched by the Royal Navy in 1906, packed a uniform main battery of heavy guns (ten 12-inch guns in her case) all of the same calibre, mounted on a single class of fire control system. This was revolutionary. Earlier battleships mixed gun sizes, making gunnery calculations messy. The dreadnought's uniform armament, combined with steam turbine propulsion and thicker armour belt, made every older battleship look timid by comparison.

The term became generic almost immediately. Within a decade, every major naval power was building dreadnoughts or "super-dreadnoughts" with bigger guns, thicker plate, and better engines. A typical dreadnought of the 1910s displaced 20,000 to 35,000 tons and carried four or five turrets, each housing two or three guns of 12 to 15 inches. Speed ranged from 18 to 21 knots. The cost was enormous: a single dreadnought could consume half a nation's naval building budget in a year.

Design variants and tactical limits

Navies experimented with layouts. Some placed turrets en echelon (offset) to allow more guns to fire broadside. Others built battlecruisers: dreadnought-type ships with lighter armour but higher speed (23 to 26 knots) for scouting and commerce raiding. The battlecruiser proved a dangerous compromise; at Jutland in 1916, three British battlecruisers blew up when hit by German shells that punched through their thinner belts. The dreadnought's real weakness was submarine and air attack. Armour protected you from gunfire, not from a torpedo in the magazine or a bomb from above. By 1940, dreadnoughts were sitting ducks for aircraft. The last true dreadnought-type battleships were commissioned in the 1940s, but they spent most of World War II hiding from air attack or being sunk by it.

In shipyards, the dreadnought represented a step change in construction discipline. Building a ship with ten heavy guns that would not tear itself apart required advances in welding, riveting, turbine design, and fire control. The guns themselves needed new recoil systems and loading mechanisms. The term "dreadnought" is slang; officially these ships were classed as battleships. In informal trade speech, "dreadnought" refers to any all-big-gun battleship of the post-1906 type, regardless of nationality or size. A Japanese dreadnought looked much like a British or American dreadnought because physics and the gun problem are universal.