Gun turret
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A gun turret (or simply turret) is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in some degree of azimuth and elevation (cone of fire).
Description
Rotating gun turrets protect the weapon and its crew as they rotate. When this meaning of the word "turret" started being used at the beginning of the 1860s, turrets were normally cylindrical.
Rotating turrets can be mounted on a
The protection provided by the turret may be against battle damage, the weather conditions, general environment in which the weapon or its crew will be operating. The name derives from the pre-existing noun turret, from the French "touret", diminutive of the word "tower",[1] meaning a self-contained protective position which is situated on top of a fortification or defensive wall as opposed to rising directly from the ground, in which case it constitutes a tower.
Cupolas
A small turret, or sub-turret set on top of a larger one, is called a cupola. The term cupola is also used for a rotating turret that carries a sighting device rather than weaponry, such as that used by a tank commander.[i]
Warships
Before the development of large-calibre, long-range guns in the mid-19th century, the classic battleship design[ii] used rows of gunport-mounted guns on each side of the ship, often mounted in casemates. Firepower was provided by a large number of guns, each of which could traverse only in a limited arc. 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. Additionally casemate mounts had to be recessed into the side of a vessel to afford a wide arc of fire, and such recesses presented shot traps, compromising the integrity of armour plating.[dubious ]
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. These presented the opportunity to concentrate firepower in fewer, better-sited positions by eliminating redundancy, in other words combining the firepower of those guns unable to engage an enemy because they sited on the wrong beam into a more powerful, and more versatile unified battery.[dubious ]
History
Designs for a rotating gun turret date back to the late 18th century.[2] In the mid-19th century, during the Crimean War, Captain Cowper Phipps Coles constructed a raft with guns protected by a 'cupola' and used the raft,[i] named the Lady Nancy, to shell the Russian town of Taganrog in the Black Sea during the Siege of Taganrog. The Lady Nancy "proved a great success"[3] and Coles patented his rotating turret design after the war.
United Kingdom: Early designs
The
The Admiralty accepted the principle of the turret gun as a useful innovation, and incorporated it into other new designs. Coles submitted a design for a ship having ten domed turrets each housing two large guns.
The design was rejected as impractical, although the Admiralty remained interested in turret ships and instructed its own designers to create better designs. Coles enlisted the support of
While Coles designed the turrets, the ship was the responsibility of Chief Constructor Isaac Watts.[4] Another ship using Coles' turret designs, HMS Royal Sovereign, was completed in August 1864. 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.[4]
Early ships like the Royal Sovereign had little sea-keeping qualities being limited to coastal waters. Sir
United States: USS Monitor
The gun turret was independently invented in the United States by the Swedish inventor
A small, armoured
Including the guns, the turret weighed approximately 160 long tons (179 short tons; 163 t); the entire weight rested on an iron spindle that had to be jacked up using a wedge before the turret was free to rotate.[8] The spindle was 9 inches (23 cm) in diameter which gave it ten times the strength needed in preventing the turret from sliding sideways.[11]
When not in use, the turret rested on a brass ring on the deck that was intended to form a watertight seal. However, in service, the interface between the turret and deck ring heavily leaked, despite
The gap between the turret and the deck proved to be another kind of problem for several Passaic-class monitors, which used the same turret design, as debris and shell fragments entered the gap and jammed the turrets during the First Battle of Charleston Harbor in April 1863.[12] Direct hits at the turret with heavy shot also had the potential to bend the spindle, which could also jam the turret.[13][14][15]
Monitor was originally intended to mount a pair of 15-inch (380 mm) smoothbore Dahlgren guns, but they were not ready in time and 11-inch (280 mm) guns were substituted,[8] each gun weighing approximately 16,000 pounds (7,300 kg). Monitor's guns used the standard propellant charge of 15 pounds (6.8 kg) specified by the 1860 ordnance instructions for targets "distant", "near", and "ordinary", established by the gun's designer Dahlgren himself.[16] They could fire a 136-pound (61.7 kg) round shot or shell up to a range of 3,650 yards (3,340 m) at an elevation of +15°.[17][18]
Later designs
The US Navy tried to save weight and deck space, and allow the much faster firing
With the advent of the
Like
The largest warship turrets were in World War II battleships where a heavily armoured enclosure protected the large gun crew during battle. The calibre of the main armament on large battleships was typically 300 to 460 mm (12 to 18 in). The turrets carrying three 460 mm (18 in) guns of
Layout
In naval terms, turret traditionally and specifically refers to a gun mounting where the entire mass rotates as one, and has a trunk that projects below the deck. The rotating part of a turret seen above deck is the gunhouse, which protects the mechanism and crew, and is where the guns are loaded. The gunhouse is supported on a bed of rotating rollers, and is not necessarily physically attached to the ship at the base of the rotating structure. In the case of the German battleship Bismarck, the turrets were not vertically restrained and fell out when she sank. The British battlecruiser Hood, like some American battleships, did have vertical restraints.[19]
Below the gunhouse there may be a working chamber, where ammunition is handled, and the main trunk, which accommodates the shell and propellant hoists that bring ammunition up from the magazines below. There may be a combined hoist (cf the animated British turret) or separate hoists (cf the US turret cutaway). The working chamber and trunk rotate with the gunhouse, and sit inside a protective armoured barbette. The barbette extends down to the main armoured deck (red in the animation). At the base of the turret sit handing rooms, where shell and propelling charges are passed from the shell room and magazine to the hoists.
The handling equipment and hoists are complex arrangements of machinery that transport the shells and charges from the magazine into the base of the turret. Bearing in mind that shells can weigh around a 5 long tons (5.6 short tons; 5.1 t), the hoists have to be powerful and rapid; a 15 inches (380 mm) turret of the type in the animation was expected to perform a complete loading and firing cycle in a minute.[20]
The loading system is fitted with a series of
As the hoist and breech must be aligned for ramming to occur, there is generally a restricted range of elevations at which the guns can be loaded; the guns return to the loading elevation, are loaded, then return to the target elevation, at which time they are said to be "in battery". The animation illustrates a turret where the rammer is fixed to the cradle that carries the guns, allowing loading to occur across a wider range of elevations.
Earlier turrets differed significantly in their operating principles. It was not until the last of the "rotating drum" designs described in the previous section were phased out that the "hooded barbette" arrangement above became the standard.
Wing turrets
A wing turret is a gun turret mounted along the side, or the wings, of a warship, off the centerline.
The positioning of a wing turret limits the gun's arc of fire, so that it generally can contribute to only the broadside weight of fire on one side of the ship. This is the major weakness of wing turrets as broadsides were the most prevalent type of gunnery duels. Depending on the configurations of ships, such as HMS Dreadnought but not SMS Blücher, the wing turrets could fire fore and aft, so this somewhat reduced the danger when an opponent crossed the T enabling it to fire a full broadside.
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.
Wing turrets were commonplace on
In the early 1900s, weapon performance,
Larger and later dreadnought battleships carried superimposed or superfiring turrets (i.e. one turret mounted higher than and firing over those in front of and below it). This allowed all turrets to train on either beam, and increased the weight of fire forward and aft. 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
Modern turrets
Many modern surface warships have mountings for larger calibre guns, although the calibres are now generally between 3 and 5 inches (76 and 127 mm) for use against both
Turret identification
On board warships, each turret is given an identification. In the British Royal Navy, these would be letters: "A" and "B" were for the turrets from the front of the ship backwards in front of the bridge, and letters near the end of the alphabet (i.e., "X", "Y", etc.) were for turrets behind the bridge ship, "Y" being the rearmost. Mountings in the middle of the ship would be "P", "Q", "R", etc.[21] Confusingly, the Dido-class cruisers had a "Q" and the Nelson-class battleships had an "X" turret in what would logically be "C" position; the latter being mounted at the main deck level in front of the bridge and behind the "B" turret, thus having restricted training fore and aft.[v]
Secondary turrets were named "P" and "S" (
There were exceptions; the battleship HMS Agincourt had the uniquely large number of seven turrets. These were numbered "1" to "7" but were unofficially nicknamed "Sunday", Monday", etc. through to "Saturday".[citation needed]
In German use, turrets were generally named "A", "B", "C", "D", "E", going from bow to stern. Usually the
In the
Aircraft
History
During World War I, air gunners initially operated guns that were mounted on pedestals or swivel mounts known as pintles. The latter evolved into the Scarff ring, a rotating ring mount which allowed the gun to be turned to any direction with the gunner remaining directly behind it, the weapon held in an intermediate elevation by bungee cord, a simple and effective mounting for single weapons such as the Lewis Gun though less handy when twin mounted as with the British Bristol F.2 Fighter and German "CL"-class two-seaters such as the Halberstadt and Hannover-designed series of compact two-seat combat aircraft. In a failed 1916 experiment, a variant of the SPAD S.A two-seat fighter was probably the first aircraft to be fitted with a remotely-controlled gun, which was located in a nose nacelle.
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
The first British operational bomber to carry an enclosed, power-operated turret was the
The Martin B-10 all-metal monocoque monoplane bomber introduced turret-mounted defensive armament within the United States Army Air Corps, almost simultaneously with the RAF's Overstrand biplane bomber design. 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. The production B-10B version started service with the USAAC in July 1935.
In time the number of turrets carried and the number of guns mounted increased. RAF heavy bombers of World War II such as the
As almost a 1930s "updated" adaptation of the
The concept came at a time when the standard armament of a fighter was only two machine guns and in the face of heavily armed bombers operating in formation, it was thought that a group of turret fighters would be able to concentrate their fire flexibly on the bombers; making beam, stern and rising attacks practicable. Although the idea had some merits in attacking unescorted bombers the weight and drag penalty of the turret (and gunner) put them at a disadvantage when Germany was able to escort its bombers with fighters from bases in Northern France. By this point British fighters were flying with eight machine guns which concentrated firepower for use in single fleeting attacks of fighters against bombers.
Attempts to put this heavier armament, such as multiple
In the US, the large, purpose-built
The intended replacement for the German
The US B-29 Superfortress had four remotely controlled turrets, comprising two dorsal and two ventral turrets. These were controlled from a trio of hemispherical, glazed, gunner-manned "astrodome" sighting stations operated from the pressurised sections in the nose and middle of the aircraft, each housing an altazimuth mounted pivoting gunsight to aim one or more of the unmanned remote turrets as needed, in addition to a B-17 style flexible manned tail gunner's station.
The defensive turret on bombers fell from favour with the realization that bombers could not attempt heavily defended targets without escort regardless of their defensive armament unless very high loss rates were acceptable and the performance penalty from the weight and drag of turrets reduced speed, range and payload and increased the number of crew required. 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.
A small number of aircraft continued to use turrets, in particular maritime patrol aircraft such as the
Layout
Aircraft carry their turrets in various locations:
- "dorsal" – on top of the fuselage, sometimes referred to as a mid-upper turret.
- "ventral" – underneath the fuselage, often on US heavy bombers, a Sperry-designed ball turret.
- "rear" or "tail" – at the very end of the fuselage.
- "nose" – at the front of the fuselage.
- "cheek" – on the flanks of the nose, as single-gun flexible defensive mounts for B-17 and B-24 heavy bombers
- "chin" – below the nose of the aircraft as on later versions of the Boeing B-17 Flying Fortress.
- "wing" – a handful of very large aircraft, such as the Messerschmitt Me 323 and the Blohm & Voss BV 222, had manned turrets in the wings
- "waist" or "beam" – mounted on the sides of the rear fuselage e.g. US twin- and four-engined bombers.
Gallery
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Consolidated B-24J Liberator nose turret
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Dorsal gun turret on aGrumman TBM Avenger
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B-29 remote controlled aft ventral turret
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Wing turrets of an Me 323
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Avro Lancaster tail turret
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The tail turret or "barbette" of a Boeing B-52 Stratofortress
Combat vehicles
History
Amongst the first armoured vehicles to be equipped with a gun turret were the
However, the first
In the 1930s, several nations produced multi-turreted tanks—probably influenced by the experimental British Vickers A1E1 Independent of 1926. Those that saw combat during the early part of World War II performed poorly and the concept was soon dropped. Combat vehicles without turrets, with the main armament mounted in the hull, or more often in a completely enclosed, integral armored casemate as part of the main hull, saw extensive use by both the German (as Sturmgeschütz and Jagdpanzer vehicles) and Soviet (as Samokhodnaya Ustanovka vehicles) armored forces during World War II as tank destroyers and assault guns. However, post-war, the concept fell out of favour due to its limitations, with the Swedish Stridsvagn 103 'S-Tank' and the German Kanonenjagdpanzer being exceptions.
Layout
In modern tanks, the turret is armoured for crew protection and rotates a full 360 degrees carrying a single large-calibre tank gun, typically in the range of 105 and 125 mm (4.1 and 4.9 in) calibre. Machine guns may be mounted inside the turret, which on modern tanks is often on a "coaxial" mount, parallel with the larger main gun.
Early designs often featured multiple weapons mounts. This concept was carried forwards into the early interwar years in Britain, Germany and the Soviet Union, arguably reaching its most absurd expression in the British Vickers A1E1 Independent tank, though this attempt was soon abandoned while the Soviet Union's similar effort produced a 'land battleship' which was actually produced and fought in defence of the Soviet Union.
In modern tanks, the turret houses all the crew except the driver (who is located in the hull). The crew located in the turret typically consist of tank commander, gunner, and often a gun loader (except in tanks that have an autoloader), while the driver sits in a separate compartment with a dedicated entry and exit, though often one that allows the driver to exit via the turret basket (fighting compartment).
For other combat vehicles, the turrets are equipped with other weapons dependent on role. An
The size of the turret is a factor in combat vehicle design. One dimension mentioned in terms of turret design is "turret ring diameter" which is the size of the aperture in the top of the chassis into which the turret is seated.
Land fortifications
In 1859, the Royal Commission on the Defence of the United Kingdom were in the process of recommending a huge programme of fortifications to protect Britain's naval bases. They interviewed Captain Coles, who had bombarded Russian fortifications during the Crimean War, however Coles repeatedly lost his temper during the discussion and the commissioners failed to ask him about the gun turret that he had patented earlier in that year, with the result that none of the Palmerston Forts mounted turrets.[26] Eventually, the Admiralty Pier Turret at Dover was commissioned in 1877 and completed in 1882.
In continental Europe, the invention of
Elsewhere, armoured turrets, sometimes described a
Some nations, from Albania to Switzerland and Austria, have embedded the turrets of obsolete tanks in concrete bunkers, while others have constructed or updated fortifications with modern artillery systems, such as the 1970s era Swedish coastal artillery battery on Landsort Island.
Gallery
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The Admiralty Pier Turret was built to protect the port of Dover in 1882.
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A German built 190 mm gun turret at Fort Copacabana in Brazil, completed in 1914.
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Turret of the Maginot Line; this could retract into the ground when not firing, for added protection.
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A twin 305 mm gun turret at Kuivasaari, Finland, completed in 1935.
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One of threeCross-Channel gun.
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12 cm tornautomatpjäs m/70 developed to defend vital points like seaports from enemy landing ships, as well as area denial and fire support, even on a nuclear battlefield.
See also
- Barbette
- Casemate
- Director (military)
- Gun carriage
- Gun mount
- Gun shield
- Rangefinder
- Remote weapon system
- Sponson
Footnotes
- ^ a b In architecture, a cupola is a small, most often dome-like, structure on top of a building, so although it is often used to describe a sub-turret such as commander's sub-turret on a tank turret, if a gun turret is mounted on a vessel or above a bunker and is dome shaped it too may be referred to as a cupola in some sources.
- ^ See box battery and central battery ship
- ^ Ericsson later admitted that this was a serious flaw in the ship's design and that the pilot house should have been placed atop the turret.
- M60A2 Patton. Given they were generally intended for an already-overburdened commander to operate, they have largely been abandoned in favour of literally lower-profile arrangements for protected observation with, in some cases, top-mounted remotely-operated weapons.
- ^ The Nelson design was an adaption of an earlier planned battleship with two turrets before the bridge and a single one behind the bridge but in front of the aft superstructure.
References
- ^ "Turret n." Online Etymology Dictionary. Retrieved 21 February 2019.
- ISBN 9780307817501. Retrieved 29 May 2017 – via Google Books.
- ISBN 978-0-85177-754-2.
- ^ a b c Barnaby, K. C. (1968). Some ship disasters and their causes. London: Hutchinson. pp. 20–30.
- ^ Barnaby, K. C. (1968). Some ship disasters and their causes. London: Hutchinson. pp. 28–29.
- ISBN 9781851094103.
- ISBN 978-1-59114-882-1.
- ^ ISSN 0043-0374.
- ISBN 978-0-8018-6250-2.
- ^ McCordock, Robert Stanley (1938). The Yankee Cheese Box. Dorrance. p. 31.
- )
- ISBN 978-0-87021-586-5.
- ^ Reed, Sir Edward James (1869). Our Iron-clad Ships: Their Qualities, Performances, and Cost. With Chapters on Turret Ships, Iron-clad Rams. London: J. Murray. pp. 253–54.
- ISBN 978-1-60344-473-6.
- ^ Wilson, H. W. (1896). Ironclads in Action: A Sketch of Naval Warfare From 1855 to 1895. Vol. 1. Boston: Little, Brown. p. 30.
- ISBN 978-1-78096-141-5.
- ISBN 978-0-88855-012-5.
- ISBN 1-86176-032-9pp. 240–42.
- CiteSeerX 10.1.1.202.317
- ISBN 1-55750-719-8
- ISBN 978-0-670-81416-9.
- ^ Reuter, Claus (2000). Development of Aircraft Turrets in the AAF, 1917–1944, Scarborough, Ont., German Canadian Museum of Applied History, p. 11.
- ^ "The Overstrand's Turret". Flight, 1936.
- ^ "Graphic of usage and stowage positions for B-17G chin turret control yoke". www.lonesentry.com.
- Dorling Kindersley, p. 59.
- ISBN 978-1-905816-04-0, pp. 46–47.
- ISBN 978-1848848139.
- ISBN 0-356-08122-2.
- ^ Hogg. p. 116
Bibliography
- Brown, J. (1977). "RCT Armament in the Boeing B-29". ISSN 0143-5450.
External links
- Media related to Gun turrets at Wikimedia Commons
- Air Gunnery Archived 2014-01-11 at the Wayback Machine November 1943 Popular Science article on aircraft turrets
- Flight article on aircraft gun turrets amongst others
- Lone Sentry's Bendix B-17 chin turret manual and details