Gun turret

Due to stability issues, fewer large (and thus heavy) guns can be carried high on a ship, but as this set casemates low and thus near the waterline they were vulnerable to flooding, effectively restricted their use to calm seas.

[dubious – discuss] Rotating turrets were weapon mounts designed to protect the crew and mechanism of the artillery piece and with the capability of being aimed and fired over a broad arc, typically between a three-quarter circle up to a full 360 degrees.

The British Admiralty ordered a prototype of Coles's patented design in 1859, which was installed in the ironclad floating battery, HMS Trusty, for trials in 1861, becoming the first warship to be fitted with a revolving gun turret.

In January 1862, the Admiralty agreed to construct a ship, HMS Prince Albert which had four turrets and a low freeboard, intended only for coastal defence.

Its existing broadside guns were replaced with four turrets on a flat deck and the ship was fitted with 5.5 inches (140 mm) of armour in a belt around the waterline.

[5] The gun turret was independently invented in the United States by the Swedish inventor John Ericsson, although his design was technologically inferior to Coles's version.

[6] Ericsson designed USS Monitor in 1861, its most prominent feature being a large, cylindrical gun turret mounted amidships above the low-freeboard upper hull, also referred to as the "raft".

A small, armoured pilot house was fitted on the upper deck towards the bow; however, its position prevented Monitor from firing her guns straight forward.

[iv] With the advent of the South Carolina-class battleships in 1908, the main battery turrets were designed so as to superfire, to improve fire arcs on centerline mounted weapons.

A similar advancement was in the Kongō-class battlecruisers and Queen Elizabeth-class battleships, which dispensed with the "Q" turret amidships in favour of heavier guns in fewer mountings.

The first ship to be built with triple turrets was the Italian Dante Alighieri, although the first to be actually commissioned was the Austro-Hungarian SMS Viribus Unitis of the Tegetthoff class.

By the beginning of World War II, most battleships used triple or, occasionally, quadruple turrets, which reduced the total number of mountings and improved armour protection.

The largest warship turrets were in World War II battleships where a heavily armoured enclosure protected the large gun crew during battle.

[21] The loading system is fitted with a series of mechanical interlocks that ensure that there is never an open path from the gunhouse to the magazine down which an explosive flash might pass.

Attempts were made to mount turrets en echelon so that they could fire on either beam, such as the Invincible-class and SMS Von der Tann battlecruisers, but this tended to cause great damage to the ships' deck from the muzzle blast.

At the time, large numbers of smaller calibre guns contributing to the broadside were thought to be of great value in demolishing a ship's upperworks and secondary armaments, as distances of battle were limited by fire control and weapon performance.

Therefore, most early dreadnought battleships featured "all big gun" armaments of identical calibre, typically 11 or 12 inches (280 or 300 mm), some of which were mounted in wing turrets.

This arrangement was not satisfactory, however, as the wing turrets not only had a reduced fire arc for broadsides, but also because the weight of the guns put great strain on the hull and it was increasingly difficult to properly armour them.

The superfiring or superimposed arrangement had not been proven until after South Carolina went to sea, and it was initially feared that the weakness of the previous Virginia-class ship's stacked turrets would repeat itself.

Modern turrets are often automatic in their operation, with no humans working inside them and only a small team passing fixed ammunition into the feed system.

As aircraft flew higher and faster, the need for protection from the elements led to the enclosure or shielding of the gun positions, as in the "lobsterback" rear seat of the Hawker Demon biplane fighter.

The Martin XB-10 prototype aircraft first featured the nose turret in June 1932—roughly a year before the less advanced Overstrand airframe design—and was first produced as the YB-10 service test version by November 1933.

Attempts to put this heavier armament, such as multiple 20 mm cannon in low profile aerodynamic turrets were explored by the British in the Boulton Paul P.92 and other designs but were not successful this class of weapons and heavier armament (up to and including artillery pieces as in the 1,420 examples produced of the American B-25G and B-25H Mitchell medium bombers and the experimental 'Tsetse' variant of the de Havilland Mosquito) being exclusively fuselage or underwing-mounted and thus aimed by pointing the aircraft.

Specifically designed to be compact and not obstruct the bombardier, this was operated by a swing-away diagonal column possessing a yoke to traverse the turret, and aimed by a reflector sight mounted in the windscreen.

By 1942, the German He 177A Greif heavy bomber would feature a Fernbedienbare Drehlafette (Remotely controlled rotary carriage) FDL 131Z remotely operated forward dorsal turret, armed with twin 13mm MG 131 machine guns on the top of the fuselage, which was operated from the astrodome a hemispherical, clear rotating observation cover, just behind the cockpit glazing and offset to starboard atop the fuselage—a second, manned powered Hydraulische Drehlafette (Hydraulic rotary mount) HDL 131 dorsal turret, further aft on the fuselage with a MG 131 was also used on most examples.

The de Havilland Mosquito light bomber was designed to operate without any defensive armament and used its speed to avoid engagement with fighters, much as the minimally armed German Schnellbomber aircraft concepts had been meant to do early in World War II.

Hetherington, designed the superstructure which consisted of armoured bodywork and a single fully rotating turret holding a regular water cooled Vickers machine gun.

However, the first tracked combat vehicles were not equipped with turrets due to the problems with getting sufficient trench crossing while keeping the centre of gravity low, and it was not until late in World War I that the French Renault FT light tank introduced the single fully rotating turret carrying the vehicle's main armament that continues to be the standard of almost every modern main battle tank and many post-World War II self-propelled guns.

In continental Europe, the invention of high explosive shells in 1885 threatened to make all existing fortifications obsolete; a partial solution was the protection of fortress guns in armoured turrets.

Mougin's designs were incorporated in a new generation of polygonal forts constructed by Raymond Adolphe Séré de Rivières in France and Henri Alexis Brialmont in Belgium.