Mortar (weapon)
Encyclopedia
A mortar is an indirect fire
weapon that fires explosive projectiles
known as (mortar) bombs at low velocities, short ranges, and high-arcing ballistic trajectories
. It is typically muzzle-loading
and has a barrel length less than 15 times its caliber
.
A mortar is relatively simple and easy to operate. A modern mortar consists of a tube into which gunners drop a purpose-designed bomb. The tube is generally set at between 45 and 85 degrees angle to the ground, with the higher angle giving shorter firing distances. The bomb has no cartridge case; the propellant is attached to the bomb's fins . When it reaches the base of the tube it hits a firing pin
, which detonates the propellant and fires the bomb. Some larger caliber mortars have a string-operated firing pin.
These attributes contrast with the mortar's larger siblings, howitzer
s and field gun
s, that fire shells
at higher velocities, longer ranges, flatter arcs, and sometimes using direct fire
. These weapons also do not use the mortar's gravity-assisted means of detonating the shell.
From the 18th to the early 20th century very heavy, relatively immobile siege
mortars were used, of up to one metre calibre, often made of cast iron and with outside barrel diameter many times that of the bore diameter. Smaller and more portable designs were introduced during the First World War, primarily for trench warfare
, which took place at relatively close ranges. Mortars continue to be in use to the present day.
Light and medium mortars are portable, and usually used by infantry
units. The chief advantage a mortar section has over an artillery
battery is the flexibility of small numbers, mobility and the ability to engage targets in the defilade
with plunging fires. Mortars are able to fire from the protection of a trench
or defilade. In these aspects the mortar is an excellent infantry support weapon, as it can be transported over any terrain and is not burdened by the logistical support
needed for artillery.
Heavy mortars are typically between 120- and 300-mm caliber. These weapons are usually towed or vehicle-mounted, sometimes breech-loaded, and normally employed by infantry units attached to battalion
through division
level. Even at this size, mortars are simpler and less expensive than comparable howitzers or field guns.
A mortar can be carried by one or more people (larger mortars can usually be broken down into components), or transported in a vehicle. An infantry mortar can usually also be mounted and fired from a mortar-carrier
, a purpose-built or modified armoured vehicle with a large roof hatch. A mortar can also be a launcher for fireworks
, a hand-held or vehicle-mounted projector for smoke shells or flares, or a large grenade launcher
. Heavy mortars can be mounted on a towed carriage, or permanently vehicle-mounted as a self-propelled mortar. Twin-barrelled self-loading mortars—such as the Patria AMOS
PT1—are the latest evolution of these heavy mortars and are mounted on platforms such as armored personnel carriers, tank chassis, and coastal patrol boats.
Modern mortars normally range in caliber
from 60 mm (2.36 in) to 120 mm (4.72 in). However, mortars both larger and smaller than these specifications have been produced. An example of the smaller scale is the British
51 mm Light Mortar
which is carried by an individual and consists of only a tube and a base plate. Conversely, a large example is the Soviet
2S4 M1975 Tyulpan
(tulip
flower) 240 mm self-propelled mortar.
Smaller mortars (up to 82 mm) are commonly used and transported by infantry based mortar sections as a substitute for, or in addition to, artillery.
Ammunition for mortars generally comes in two main varieties: fin-stabilised and spin-stabilised. The former have short fins on their posterior portion which control the path of the bomb in flight. Spin-stabilized mortar bombs rotate as they travel along and leave the mortar tube, which stabilizes them in much the same way as a rifle bullet. Both types of rounds can be either illumination (infra-red or visible illumination), smoke, or high explosive.
Spin-stabilised rounds may be fired from a smoothbore or a rifled barrel. Since mortars generally are muzzle loaded, mortar bombs for rifled barrels have a pre-engraved band, called an obturator, that engages with the rifling of the barrel. They are more accurate, but slower to load and the trajectory is affected by drift: any spinning projectile is subject to the Magnus effect
which causes the trajectory to drift perpendicular to the spin axis; this is also what makes spinning balls follow a curved trajectory in sports such as baseball, football, and tennis.
Mortars are made in a range of calibers. The French 81 mm mortar became standard for many countries, while the Soviet bloc standardized on the 82mm mortar.
Mortars suffer from instability when used on snow and soft ground, because the recoil pushes them into the ground or snow unevenly. A solution to this problem is the Raschen Bag
.
Mortars are also highly effective when used from concealed positions, such as the natural escarpments on hillsides or from woods, especially if forward observers are being employed in strategic positions to direct fire; an arrangement where the mortar is in relatively close proximity both to its FO and its target, allowing for fire to be quickly and accurately delivered to lethal effect.
Fin-stabilized mortar bombs do not have to withstand the rotational forces placed upon them by rifling, and can carry a higher payload in a thinner skin than rifled artillery ammunition. Due to the difference in available volume a smooth-bore mortar of a given diameter will have a greater explosive yield than a similarly sized artillery shell. For example a 120 mm mortar bomb has about the same explosive capability as a 155 mm artillery shell. Also, fin-stabilized munitions fired from a smooth-bore, which do not rely upon the spin imparted by a rifled-bore for greater accuracy, do not have the drawback of veering in the direction of the spin.
such as cordite
. There is usually a trigger mechanism built into the base of the spigot, with a long firing pin running up the length of the spigot activating a primer
inside the projectile and firing the propellant charge.
The advantage of a spigot mortar is that the firing unit (baseplate and spigot) is smaller and lighter than a conventional tube mortar of equivalent payload and range. It is also somewhat simpler to manufacture.
The disadvantage is that while most mortar bombs have a streamlined shape towards the back that fits a spigot mortar application well, using that space for the spigot mortar tube takes volume and mass away from the payload of the projectile. If a soldier is carrying only a few projectiles, the projectile weight disadvantage is not significant. However, the weight of a large quantity of the heavier and more complex spigot projectiles offsets the weight saved due to the spigot mortar being lighter than a conventional mortar.
A near-silent mortar can operate using the spigot principle. Each round has a close-fitting movable plug in the tube that fits over the spigot. When the round is fired, the projectile is pushed off the spigot, but before the plug clears the spigot it is caught by a constriction at the base of the tube. This traps the gases from the propelling charge and hence the sound of the firing. After World War II
the Belgium Fly-K silent spigot mortar was accepted into French service as the TN-8111.
Spigot mortars are generally out of favor in modern usage, replaced by small conventional mortars.
Military applications of spigot mortars include
Non-military applications include use of small-caliber spigot mortars to launch lightweight, low-velocity foam dummy targets used for training retriever
dogs for bird hunting. Extremely simple launchers use a separate small primer cap as the sole propellant (similar or identical to the cartridges used in industrial nail gun
s).
. A European account of the siege of Belgrade (1456) by Giovanni da Tagliacozzo credits the Ottomans for using seven mortars that fired "stone shots one Italian mile high". The speed of these was apparently slow enough that casualties could be avoided by posting observers that gave warning of their trajectories.
Early mortars, such as the Pumhart von Steyr
, were also large and heavy, and could not be easily transported. Simply made, these weapons were no more than iron bowls reminiscent of the kitchen and apothecary mortars from where they drew their name. An early transportable mortar was invented by Baron Menno van Coehoorn
(Siege of Grave, 1673). Coehorn-type mortars of approximately 180 pounds (81.6 kg) weight were used by both sides during the American Civil War
.
During the Russo-Japanese War
, Leonid Gobyato
for the first time applied deflection from closed firing positions in the field and with General Roman Kondratenko
designed the first mortar that fired navy shells. However, it was not until the Stokes trench mortar
devised by Sir Wilfred Stokes
in 1915, that the modern mortar transportable by one person was born. The Germans also developed a series of trench mortars or Minenwerfer
in calibers from 7.58 cm to 25 cm during World War I
, though these were rifled.
Extremely useful in the muddy trenches of the Western Front
, mortars were praised because of the bombs' high angle of flight; a mortar round could be aimed to fall directly into trench
es where artillery shells, due to their low angle of flight, could not possibly go. Modern mortars have improved upon these designs, offering a weapon that is light, adaptable, easy to operate, and yet possesses enough accuracy and firepower to provide the infantry
with quality close fire support against soft and hard targets more quickly than any other means.
During the battle of Iwo Jima
, the Imperial Japanese Army
used twelve 320 mm mortar
s against the American forces.
in 1832), Mallet's Mortar
(36 inches; 910 mm; designed by Robert Mallet
and tested by the Woolwich Arsenal, London, in 1857) and the "Little David
" (36 inches; 910 mm; developed in the United States for use in World War II
). All three mortars had a caliber
of 36 "inches", but only the "Monster Mortar" saw action (at the Battle of Antwerp in 1832).
groups, usually to attack fortified military installations. The Provisional Irish Republican Army
used some of the best-known examples during the 1970s, 1980s and 1990s. The largest types came to be known as "barracks busters
" and were usually constructed from heavy steel piping mounted on a steel frame. The largest had a caliber of 320 millimetres (12.6 in) and fired home-made rounds carrying from 80 to 100 kg (176.4 to 220.5 lb) of explosive.
As each tube fired only one round, mortars were usually deployed as a battery of four or six welded onto a steel frame. This was often concealed inside a van such as a Ford Transit
. The vehicle would be parked, pointing roughly at the target. A timer fired the propellant charges after a delay – this allowed the mortar gunner time to escape. After firing, a timer-operated incendiary device could set the vehicle on fire in order to destroy any forensic evidence it contained.
Well-known incidents using these weapons include the 1985 Newry mortar attack
, when nine members of the Royal Ulster Constabulary
were killed, and the Downing Street mortar attack
in 1991. The IRA
mortared 10 Downing Street
as a Cabinet meeting was in session. Three bombs were launched but only one detonated, it landed in the back garden of the British Prime Minister
's residence and only shattered the rear windows. Prime Minister John Major
had to move to Admiralty House
while repairs were effected.
Indirect fire
Indirect fire means aiming and firing a projectile in a high trajectory without relying on a direct line of sight between the gun and its target, as in the case of direct fire...
weapon that fires explosive projectiles
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...
known as (mortar) bombs at low velocities, short ranges, and high-arcing ballistic trajectories
Trajectory of a projectile
In physics, the ballistic trajectory of a projectile is the path that a thrown or launched projectile will take under the action of gravity, neglecting all other forces, such as friction from air resistance, without propulsion....
. It is typically muzzle-loading
Muzzleloader
A muzzleloader is any firearm into which the projectile and usually the propellant charge is loaded from the muzzle of the gun . This is distinct from the more popular modern designs of breech-loading firearms...
and has a barrel length less than 15 times its caliber
Caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
.
Function
Firing pin
A firing pin or striker is part of the firing mechanism used in a firearm or explosive device e.g. an M14 landmine or bomb fuze. Firing pins may take many forms, though the types used in landmines, bombs, grenade fuzes or other single-use devices generally have a sharpened point...
, which detonates the propellant and fires the bomb. Some larger caliber mortars have a string-operated firing pin.
These attributes contrast with the mortar's larger siblings, howitzer
Howitzer
A howitzer is a type of artillery piece characterized by a relatively short barrel and the use of comparatively small propellant charges to propel projectiles at relatively high trajectories, with a steep angle of descent...
s and field gun
Field gun
A field gun is an artillery piece. Originally the term referred to smaller guns that could accompany a field army on the march and when in combat could be moved about the battlefield in response to changing circumstances, as to opposed guns installed in a fort, or to siege cannon or mortars which...
s, that fire shells
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...
at higher velocities, longer ranges, flatter arcs, and sometimes using direct fire
Direct fire
Direct fire refers to the launching of a projectile directly at a target on a relatively flat trajectory. The firing weapon must have a sighting device and an unobstructed line of sight to the target, which means no objects or friendly units can be between it and the target...
. These weapons also do not use the mortar's gravity-assisted means of detonating the shell.
From the 18th to the early 20th century very heavy, relatively immobile siege
Siege
A siege is a military blockade of a city or fortress with the intent of conquering by attrition or assault. The term derives from sedere, Latin for "to sit". Generally speaking, siege warfare is a form of constant, low intensity conflict characterized by one party holding a strong, static...
mortars were used, of up to one metre calibre, often made of cast iron and with outside barrel diameter many times that of the bore diameter. Smaller and more portable designs were introduced during the First World War, primarily for trench warfare
Trench warfare
Trench warfare is a form of occupied fighting lines, consisting largely of trenches, in which troops are largely immune to the enemy's small arms fire and are substantially sheltered from artillery...
, which took place at relatively close ranges. Mortars continue to be in use to the present day.
Light and medium mortars are portable, and usually used by infantry
Infantry
Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...
units. The chief advantage a mortar section has over an artillery
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
battery is the flexibility of small numbers, mobility and the ability to engage targets in the defilade
Enfilade and defilade
Enfilade and defilade are concepts in military tactics used to describe a military formation's exposure to enemy fire. A formation or position is "in enfilade" if weapons fire can be directed along its longest axis. A unit or position is "in defilade" if it uses natural or artificial obstacles to...
with plunging fires. Mortars are able to fire from the protection of a trench
Trench
A trench is a type of excavation or depression in the ground. Trenches are generally defined by being deeper than they are wide , and by being narrow compared to their length ....
or defilade. In these aspects the mortar is an excellent infantry support weapon, as it can be transported over any terrain and is not burdened by the logistical support
Logistics
Logistics is the management of the flow of goods between the point of origin and the point of destination in order to meet the requirements of customers or corporations. Logistics involves the integration of information, transportation, inventory, warehousing, material handling, and packaging, and...
needed for artillery.
Heavy mortars are typically between 120- and 300-mm caliber. These weapons are usually towed or vehicle-mounted, sometimes breech-loaded, and normally employed by infantry units attached to battalion
Battalion
A battalion is a military unit of around 300–1,200 soldiers usually consisting of between two and seven companies and typically commanded by either a Lieutenant Colonel or a Colonel...
through division
Division (military)
A division is a large military unit or formation usually consisting of between 10,000 and 20,000 soldiers. In most armies, a division is composed of several regiments or brigades, and in turn several divisions typically make up a corps...
level. Even at this size, mortars are simpler and less expensive than comparable howitzers or field guns.
A mortar can be carried by one or more people (larger mortars can usually be broken down into components), or transported in a vehicle. An infantry mortar can usually also be mounted and fired from a mortar-carrier
Self-propelled artillery
Self-propelled artillery vehicles are combat vehicles armed with artillery. Within the term are covered self-propelled guns and rocket artillery...
, a purpose-built or modified armoured vehicle with a large roof hatch. A mortar can also be a launcher for fireworks
Fireworks
Fireworks are a class of explosive pyrotechnic devices used for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display. A fireworks event is a display of the effects produced by firework devices...
, a hand-held or vehicle-mounted projector for smoke shells or flares, or a large grenade launcher
Grenade launcher
A grenade launcher or grenade discharger is a weapon that launches a grenade with more accuracy, higher velocity, and to greater distances than a soldier could throw it by hand....
. Heavy mortars can be mounted on a towed carriage, or permanently vehicle-mounted as a self-propelled mortar. Twin-barrelled self-loading mortars—such as the Patria AMOS
AMOS
AMOS or Advanced Mortar System is a 120 mm automatic twin barrelled, breech loaded mortar turret. AMOS has been fitted to a wide range of armoured vehicles such as the Sisu Pasi, Patria AMV, Combat Vehicle 90 or Combat Boat 90....
PT1—are the latest evolution of these heavy mortars and are mounted on platforms such as armored personnel carriers, tank chassis, and coastal patrol boats.
Design
Most modern mortar systems consist of three main components: a barrel, a base plate, and a bipod.Modern mortars normally range in caliber
Caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
from 60 mm (2.36 in) to 120 mm (4.72 in). However, mortars both larger and smaller than these specifications have been produced. An example of the smaller scale is the British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
51 mm Light Mortar
L9A1 51 mm Light Mortar
The L9A1 51 mm Light Mortar is a man-portable mortar system used by the British Army. Smoke, illuminating and high explosive bombs are available. A short range insert device allows the weapon to be used in a direct fire mode...
which is carried by an individual and consists of only a tube and a base plate. Conversely, a large example is the Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
2S4 M1975 Tyulpan
2S4 Tyulpan
The 2S4 Tyulpan is a Soviet self-propelled mortar. "2S4" is its GRAU designation.It was identified for the first time in 1975 in the Soviet army and so was called M-1975 by NATO , whereas its official designation is SM-240...
(tulip
Tulip
The tulip is a perennial, bulbous plant with showy flowers in the genus Tulipa, which comprises 109 species and belongs to the family Liliaceae. The genus's native range extends from as far west as Southern Europe, North Africa, Anatolia, and Iran to the Northwest of China. The tulip's centre of...
flower) 240 mm self-propelled mortar.
Smaller mortars (up to 82 mm) are commonly used and transported by infantry based mortar sections as a substitute for, or in addition to, artillery.
Ammunition for mortars generally comes in two main varieties: fin-stabilised and spin-stabilised. The former have short fins on their posterior portion which control the path of the bomb in flight. Spin-stabilized mortar bombs rotate as they travel along and leave the mortar tube, which stabilizes them in much the same way as a rifle bullet. Both types of rounds can be either illumination (infra-red or visible illumination), smoke, or high explosive.
Spin-stabilised rounds may be fired from a smoothbore or a rifled barrel. Since mortars generally are muzzle loaded, mortar bombs for rifled barrels have a pre-engraved band, called an obturator, that engages with the rifling of the barrel. They are more accurate, but slower to load and the trajectory is affected by drift: any spinning projectile is subject to the Magnus effect
Magnus effect
The Magnus effect is the phenomenon whereby a spinning object flying in a fluid creates a whirlpool of fluid around itself, and experiences a force perpendicular to the line of motion...
which causes the trajectory to drift perpendicular to the spin axis; this is also what makes spinning balls follow a curved trajectory in sports such as baseball, football, and tennis.
Mortars are made in a range of calibers. The French 81 mm mortar became standard for many countries, while the Soviet bloc standardized on the 82mm mortar.
Mortars suffer from instability when used on snow and soft ground, because the recoil pushes them into the ground or snow unevenly. A solution to this problem is the Raschen Bag
Raschen Bag
A Raschen Bag is a bag of ballast that is placed underneath the baseplate of a mortar to improve its accuracy when used on snow or other soft ground conditions. They are named after Colonel Dan Raschen, Royal Engineers, who invented them....
.
Distinctive features of mortars
Mortars and their ammunition are generally much smaller and lighter than other artillery, such as guns and howitzers, which allows light and medium (typically, 60mm and 81/82mm) mortars to be considered small-arms; i.e. capable of transport by personnel without vehicle assistance. They are short-range weapons, and often more effective than other artillery for many purposes within their shorter range. In particular, due its high, parabolic trajectory with a near vertical descent, the mortar can land bombs on nearby targets, including those behind obstacles or in fortifications, such as light vehicles behind hills or structures, or infantry in trenches or spider holes. This also makes it possible to launch attacks from positions lower than the target of the attack. (E.g., long-range artillery could not shell a target 1 km away and 30 metres (100 ft) higher; a target easily accessible to a mortar.Mortars are also highly effective when used from concealed positions, such as the natural escarpments on hillsides or from woods, especially if forward observers are being employed in strategic positions to direct fire; an arrangement where the mortar is in relatively close proximity both to its FO and its target, allowing for fire to be quickly and accurately delivered to lethal effect.
Fin-stabilized mortar bombs do not have to withstand the rotational forces placed upon them by rifling, and can carry a higher payload in a thinner skin than rifled artillery ammunition. Due to the difference in available volume a smooth-bore mortar of a given diameter will have a greater explosive yield than a similarly sized artillery shell. For example a 120 mm mortar bomb has about the same explosive capability as a 155 mm artillery shell. Also, fin-stabilized munitions fired from a smooth-bore, which do not rely upon the spin imparted by a rifled-bore for greater accuracy, do not have the drawback of veering in the direction of the spin.
Spigot mortar
Spigot mortars, a particular type of mortar, consist of a mostly solid rod or spigot, onto which a hollow tube in the projectile fits - inverting the normal tube-mortar arrangement. At the top of the tube in the projectile, a cavity contains propellantPropellant
A propellant is a material that produces pressurized gas that:* can be directed through a nozzle, thereby producing thrust ;...
such as cordite
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance...
. There is usually a trigger mechanism built into the base of the spigot, with a long firing pin running up the length of the spigot activating a primer
Percussion cap
The percussion cap, introduced around 1830, was the crucial invention that enabled muzzleloading firearms to fire reliably in any weather.Before this development, firearms used flintlock ignition systems which produced flint-on-steel sparks to ignite a pan of priming powder and thereby fire the...
inside the projectile and firing the propellant charge.
The advantage of a spigot mortar is that the firing unit (baseplate and spigot) is smaller and lighter than a conventional tube mortar of equivalent payload and range. It is also somewhat simpler to manufacture.
The disadvantage is that while most mortar bombs have a streamlined shape towards the back that fits a spigot mortar application well, using that space for the spigot mortar tube takes volume and mass away from the payload of the projectile. If a soldier is carrying only a few projectiles, the projectile weight disadvantage is not significant. However, the weight of a large quantity of the heavier and more complex spigot projectiles offsets the weight saved due to the spigot mortar being lighter than a conventional mortar.
A near-silent mortar can operate using the spigot principle. Each round has a close-fitting movable plug in the tube that fits over the spigot. When the round is fired, the projectile is pushed off the spigot, but before the plug clears the spigot it is caught by a constriction at the base of the tube. This traps the gases from the propelling charge and hence the sound of the firing. After World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
the Belgium Fly-K silent spigot mortar was accepted into French service as the TN-8111.
Spigot mortars are generally out of favor in modern usage, replaced by small conventional mortars.
- The 290 mm petard mortar used on the Churchill AVRE by Britain in World War II
- The 320 mm Type 98 mortar used by Japan in World War II to some psychological effect in the battles of Iwo JimaIwo JimaIwo Jima, officially , is an island of the Japanese Volcano Islands chain, which lie south of the Ogasawara Islands and together with them form the Ogasawara Archipelago. The island is located south of mainland Tokyo and administered as part of Ogasawara, one of eight villages of Tokyo...
and Okinawa
- Anti-tank launchers
- The Blacker BombardBlacker BombardThe Blacker Bombard, also known as the 29mm Spigot Mortar, was an infantry anti-tank weapon devised by Lieutenant-Colonel Stewart Blacker in the early years of the Second World War.-Development:...
and PIATPIATThe Projector, Infantry, Anti Tank was a British hand-held anti-tank weapon developed during the Second World War. The PIAT was designed in 1942 in response to the British Army's need for a more effective infantry anti-tank weapon, and entered service in 1943.The PIAT was based on the spigot...
anti-tank launcher used by Britain in World War II utilised a spigot mortar type of launcher.
- The Blacker Bombard
- Anti-submarine launchers
- The HedgehogHedgehog (weapon)The Hedgehog was an anti-submarine weapon developed by the Royal Navy during World War II, that was deployed on convoy escort warships such as destroyers to supplement the depth charge. The weapon worked by firing a number of small spigot mortar bombs from spiked fittings...
launcher, used from the deck of a ship, used 24 spigot mortars which fired a circular pattern of anti-submarine projectiles into the sea ahead of the ship. A sinking projectile detonated if it struck a submarine, and the pattern was such that any submarine partly in the landing zone of the projectiles would be struck one or more times.
- The Hedgehog
Non-military applications include use of small-caliber spigot mortars to launch lightweight, low-velocity foam dummy targets used for training retriever
Retriever
A retriever is a type of gun dog that retrieves game for a hunter. Generally gun-dogs are divided into three major classifications: retrievers, flushing spaniels, and pointing breeds. Retrievers were bred primarily to retrieve birds or other prey and return them to the hunter without damage...
dogs for bird hunting. Extremely simple launchers use a separate small primer cap as the sole propellant (similar or identical to the cartridges used in industrial nail gun
Nail gun
A nail gun, nailgun or nailer is a type of tool used to drive nails into wood or some other kind of material. It is usually driven by electromagnetism, compressed air , highly flammable gases such as butane or propane, or, for powder-actuated tools, a small explosive charge...
s).
History
Mortars have existed for hundreds of years, first seeing use in siege warfare. Turkish historians claim that the first mortars were used at the 1453 siege of ConstantinopleFall of Constantinople
The Fall of Constantinople was the capture of the capital of the Byzantine Empire, which occurred after a siege by the Ottoman Empire, under the command of Ottoman Sultan Mehmed II, against the defending army commanded by Byzantine Emperor Constantine XI...
. A European account of the siege of Belgrade (1456) by Giovanni da Tagliacozzo credits the Ottomans for using seven mortars that fired "stone shots one Italian mile high". The speed of these was apparently slow enough that casualties could be avoided by posting observers that gave warning of their trajectories.
Early mortars, such as the Pumhart von Steyr
Pumhart von Steyr
The Pumhart von Steyr is a medieval supergun from Styria, Austria, and the largest known wrought-iron bombard by caliber. The cannon was produced in the early 15th century and could fire, according to modern calculations, a 690 kg stone ball around 600 m, loaded with 15 kg of powder and set up at...
, were also large and heavy, and could not be easily transported. Simply made, these weapons were no more than iron bowls reminiscent of the kitchen and apothecary mortars from where they drew their name. An early transportable mortar was invented by Baron Menno van Coehoorn
Menno van Coehoorn
Menno, Baron van Coehoorn was a Dutch soldier and military engineer of Swedish extraction. He made a number of influential weaponry innovations in siege warfare and fortification techniques...
(Siege of Grave, 1673). Coehorn-type mortars of approximately 180 pounds (81.6 kg) weight were used by both sides during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...
.
During the Russo-Japanese War
Russo-Japanese War
The Russo-Japanese War was "the first great war of the 20th century." It grew out of rival imperial ambitions of the Russian Empire and Japanese Empire over Manchuria and Korea...
, Leonid Gobyato
Leonid Gobyato
Leonid Nikolaevich Gobyato was a lieutenant-general in the Imperial Russian Army and designer of the modern, man-portable mortar.-Biography:...
for the first time applied deflection from closed firing positions in the field and with General Roman Kondratenko
Roman Kondratenko
Roman Isidorovich Kondratenko was a general in the Imperial Russian Army famous for his devout defense of Port Arthur during the Russo-Japanese War of 1904-1905.- Biography :...
designed the first mortar that fired navy shells. However, it was not until the Stokes trench mortar
Stokes Mortar
The Stokes mortar was a British trench mortar invented by Sir Wilfred Stokes KBE which was issued to the British Army and the Commonwealth armies during the latter half of the First World War.-History:...
devised by Sir Wilfred Stokes
Wilfred Stokes
-External links:...
in 1915, that the modern mortar transportable by one person was born. The Germans also developed a series of trench mortars or Minenwerfer
Minenwerfer
Minenwerfer is the German name for a class of short range mortars used extensively during the First World War by the German Army...
in calibers from 7.58 cm to 25 cm during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, though these were rifled.
Extremely useful in the muddy trenches of the Western Front
Western Front (World War I)
Following the outbreak of World War I in 1914, the German Army opened the Western Front by first invading Luxembourg and Belgium, then gaining military control of important industrial regions in France. The tide of the advance was dramatically turned with the Battle of the Marne...
, mortars were praised because of the bombs' high angle of flight; a mortar round could be aimed to fall directly into trench
Trench
A trench is a type of excavation or depression in the ground. Trenches are generally defined by being deeper than they are wide , and by being narrow compared to their length ....
es where artillery shells, due to their low angle of flight, could not possibly go. Modern mortars have improved upon these designs, offering a weapon that is light, adaptable, easy to operate, and yet possesses enough accuracy and firepower to provide the infantry
Infantry
Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...
with quality close fire support against soft and hard targets more quickly than any other means.
During the battle of Iwo Jima
Battle of Iwo Jima
The Battle of Iwo Jima , or Operation Detachment, was a major battle in which the United States fought for and captured the island of Iwo Jima from the Empire of Japan. The U.S...
, the Imperial Japanese Army
Imperial Japanese Army
-Foundation:During the Meiji Restoration, the military forces loyal to the Emperor were samurai drawn primarily from the loyalist feudal domains of Satsuma and Chōshū...
used twelve 320 mm mortar
320 mm mortar
The 320 mm Type 98 mortar , was an artillery weapon used by the Japanese military during World War II, especially during the Battle of Iwo Jima.-Specifications:...
s against the American forces.
Largest mortars
The largest mortars ever developed were the French "Monster Mortar" (36 French inches; 975 mm; developed by Henri-Joseph PaixhansHenri-Joseph Paixhans
Henri-Joseph Paixhans was a French artillery officer of the beginning of the 19th century.Henri-Joseph Paixhans graduated from the École Polytechnique...
in 1832), Mallet's Mortar
Mallet's Mortar
Mallet's Mortar was a British siege mortar built for, but never used in, the Crimean WarThe mortar was design by Robert Mallet. It was constructed in sections so that it could be transported....
(36 inches; 910 mm; designed by Robert Mallet
Robert Mallet
Robert Mallet FRS , Irish geophysicist, civil engineer, and inventor who distinguished himself in research on earthquakes and is sometimes called the father of seismology.-Early life:...
and tested by the Woolwich Arsenal, London, in 1857) and the "Little David
Little David
Little David was the nickname of an American 36 inch caliber mortar used for test firing aerial bombs during World War II.-History:...
" (36 inches; 910 mm; developed in the United States for use in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
). All three mortars had a caliber
Caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
of 36 "inches", but only the "Monster Mortar" saw action (at the Battle of Antwerp in 1832).
Improvised mortars
Improvised, or "homemade", mortars have been used by insurgentInsurgency
An insurgency is an armed rebellion against a constituted authority when those taking part in the rebellion are not recognized as belligerents...
groups, usually to attack fortified military installations. The Provisional Irish Republican Army
Provisional Irish Republican Army
The Provisional Irish Republican Army is an Irish republican paramilitary organisation whose aim was to remove Northern Ireland from the United Kingdom and bring about a socialist republic within a united Ireland by force of arms and political persuasion...
used some of the best-known examples during the 1970s, 1980s and 1990s. The largest types came to be known as "barracks busters
Barrack buster
Barrack buster is the colloquial name given to several improvised mortars, developed in the 1990s by the engineering group of the Provisional Irish Republican Army ....
" and were usually constructed from heavy steel piping mounted on a steel frame. The largest had a caliber of 320 millimetres (12.6 in) and fired home-made rounds carrying from 80 to 100 kg (176.4 to 220.5 lb) of explosive.
As each tube fired only one round, mortars were usually deployed as a battery of four or six welded onto a steel frame. This was often concealed inside a van such as a Ford Transit
Ford Transit
The Ford Transit is a range of panel vans, minibuses, and pickup trucks, produced by the Ford Motor Company in Europe.The Transit has been the best-selling light commercial vehicle in Europe for 40 years, and in some countries the term "Transit" has passed into common usage as a generic term...
. The vehicle would be parked, pointing roughly at the target. A timer fired the propellant charges after a delay – this allowed the mortar gunner time to escape. After firing, a timer-operated incendiary device could set the vehicle on fire in order to destroy any forensic evidence it contained.
Well-known incidents using these weapons include the 1985 Newry mortar attack
1985 Newry mortar attack
The 1985 Newry mortar attack was an attack carried out by the Provisional Irish Republican Army on a Royal Ulster Constabulary station in Corry Square, Newry, Northern Ireland. The attack killed nine RUC officers.-Background:...
, when nine members of the Royal Ulster Constabulary
Royal Ulster Constabulary
The Royal Ulster Constabulary was the name of the police force in Northern Ireland from 1922 to 2000. Following the awarding of the George Cross in 2000, it was subsequently known as the Royal Ulster Constabulary GC. It was founded on 1 June 1922 out of the Royal Irish Constabulary...
were killed, and the Downing Street mortar attack
Downing Street mortar attack
The Downing Street mortar attack was carried out by the Provisional Irish Republican Army on 10 Downing Street, London, the British Prime Minister John Major's official residence. The 7 February 1991 attack, an assassination attempt on Major and his War Cabinet who were meeting to discuss the...
in 1991. The IRA
Provisional Irish Republican Army
The Provisional Irish Republican Army is an Irish republican paramilitary organisation whose aim was to remove Northern Ireland from the United Kingdom and bring about a socialist republic within a united Ireland by force of arms and political persuasion...
mortared 10 Downing Street
10 Downing Street
10 Downing Street, colloquially known in the United Kingdom as "Number 10", is the headquarters of Her Majesty's Government and the official residence and office of the First Lord of the Treasury, who is now always the Prime Minister....
as a Cabinet meeting was in session. Three bombs were launched but only one detonated, it landed in the back garden of the British Prime Minister
Prime Minister of the United Kingdom
The Prime Minister of the United Kingdom of Great Britain and Northern Ireland is the Head of Her Majesty's Government in the United Kingdom. The Prime Minister and Cabinet are collectively accountable for their policies and actions to the Sovereign, to Parliament, to their political party and...
's residence and only shattered the rear windows. Prime Minister John Major
John Major
Sir John Major, is a British Conservative politician, who served as Prime Minister of the United Kingdom and Leader of the Conservative Party from 1990–1997...
had to move to Admiralty House
Admiralty House (London)
Admiralty House in London is a Grade I listedbuilding facing Whitehall, currently used for UK government functions and as ministerial flats. It was opened in 1788 and until 1964 was the official residence of First Lords of the Admiralty.-Description:...
while repairs were effected.
See also
- List of heavy mortars
- List of infantry mortars
- Carcass (projectile)Carcass (projectile)A carcass was an early form of incendiary bomb or shell, intended to set targets on fire. It comprised an external casing, usually of cast iron, filled with a highly flammable mixture, and having three to five holes through which the burning filling could blaze outward...
, used in mortars before the modern age - Military technology and equipment
- Chemical mortar battalionChemical mortar battalionThe United States chemical mortar battalions were army units attached to U.S. Infantry divisions, and it was their responsibility to service the 4.2 in chemical mortar during World War II. For this reason they were also called the "Four-deucers"....
s of the United States ArmyUnited States ArmyThe United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services... - Strix mortar roundStrix mortar roundThe Saab Bofors Dynamics STRIX is a Swedish guided projectile fired from a 120 mm mortar.STRIX is fired like a conventional mortar round. The round contains an infrared sensor that it uses to guide itself onto any tank or armoured fighting vehicle in the vicinity where it lands.STRIX has been in...
- HedgehogHedgehog (weapon)The Hedgehog was an anti-submarine weapon developed by the Royal Navy during World War II, that was deployed on convoy escort warships such as destroyers to supplement the depth charge. The weapon worked by firing a number of small spigot mortar bombs from spiked fittings...
World War II anti-submarine weapons - Barrack busterBarrack busterBarrack buster is the colloquial name given to several improvised mortars, developed in the 1990s by the engineering group of the Provisional Irish Republican Army ....
- M2 4.2 Inch MortarM2 4.2 inch mortar-External links:* early detailed article on 4.2 mortar...
- 2S4 Tyulpan2S4 TyulpanThe 2S4 Tyulpan is a Soviet self-propelled mortar. "2S4" is its GRAU designation.It was identified for the first time in 1975 in the Soviet army and so was called M-1975 by NATO , whereas its official designation is SM-240...
- Mortar carrierMortar carrierA mortar carrier, also known as a self-propelled mortar, is a self-propelled artillery vehicle carrying a mortar as it's primary weapon. Mortar carriers cannot be fired while on the move and some must be dismounted to fire.In U.S...
Further reading
- FM 3-22.90 Mortars - 7 Dec 2007(US Army)
- FM 3-22.91 Mortar Fire Direction Procedures - 17 July 2008 (US Army)
External links
- Mallet's Mortar, the largest British mortar ever made.
- Defense Update: Modern Mobile 120mm Mortars
- Defense Update: Advanced Mortar Munitions
- Mortars during World War I
- The Karl Morser, WW IIWorld War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
-era German 60 cm self-propelled mortar. - Video (streaming wmv)