Martin von Wahrendorff , and Joseph Whitworth independently produced rifled cannon in the s, but it was Armstrong's gun that was first to see widespread use during the Crimean War. This spin, together with the elimination of windage as a result of the tight fit, enabled the gun to achieve greater range and accuracy than existing smooth-bore muzzle-loaders with a smaller powder charge. His gun was also a breech-loader. Although attempts at breech-loading mechanisms had been made since medieval times, the essential engineering problem was that the mechanism couldn't withstand the explosive charge.
It was only with the advances in metallurgy and precision engineering capabilities during the Industrial Revolution that Armstrong was able to construct a viable solution. The gun combined all the properties that make up an effective artillery piece. The gun was mounted on a carriage in such a way as to return the gun to firing position after the recoil. What made the gun really revolutionary lay in the technique of the construction of the gun barrel that allowed it to withstand much more powerful explosive forces.
The " built-up " method involved assembling the barrel with wrought-iron later mild steel was used tubes of successively smaller diameter. When it cooled the gun would contract although not back to its original size, which allowed an even pressure along the walls of the gun which was directed inward against the outward forces that the gun's firing exerted on the barrel.
Another innovative feature, more usually associated with 20th-century guns, was what Armstrong called its "grip", which was essentially a squeeze bore ; the 6 inches of the bore at the muzzle end was of slightly smaller diameter, which centered the shell before it left the barrel and at the same time slightly swaged down its lead coating, reducing its diameter and slightly improving its ballistic qualities.
Armstrong's system was adopted in , initially for "special service in the field" and initially he produced only smaller artillery pieces, 6-pounder 2. The first cannon to contain all 'modern' features is generally considered to be the French 75 of Since it did not need to be re-aimed after each shot, the crew could fire as soon as the barrel returned to its resting position.
In typical use, the French 75 could deliver fifteen rounds per minute on its target, either shrapnel or melinite high-explosive , up to about 5 miles 8, m away. Its firing rate could even reach close to 30 rounds per minute, albeit only for a very short time and with a highly experienced crew.
These were rates that contemporary bolt action rifles could not match. The gun used cased ammunition, was breech-loading, and had modern sights, a self-contained firing mechanism and hydro-pneumatic recoil dampening. Indirect fire, the firing of a projectile without relying on direct line of sight between the gun and the target, possibly dates back to the 16th century. In , Russian Lieutenant Colonel KG Guk published Indirect Fire for Field Artillery , which provided a practical method of using aiming points for indirect fire by describing, "all the essentials of aiming points, crest clearance, and corrections to fire by an observer".
Despite conservative opposition within the German army , indirect fire was adopted as doctrine by the s. In the early s, Goertz in Germany developed an optical sight for azimuth laying. The British halfheartedly experimented with indirect fire techniques since the s, but with the onset of the Boer War , they were the first to apply the theory in practice in , although they had to improvise without a lining-plane sight. In the next 15 years leading up to World War I , the techniques of indirect fire became available for all types of artillery.
Indirect fire was the defining characteristic of 20th-century artillery and led to undreamt of changes in the amount of artillery, its tactics, organisation, and techniques, most of which occurred during World War I. An implication of indirect fire and improving guns was increasing range between gun and target, this increased the time of flight and the vertex of the trajectory. The result was decreasing accuracy the increasing distance between the target and the mean point of impact of the shells aimed at it caused by the increasing effects of non-standard conditions.
Indirect firing data was based on standard conditions including a specific muzzle velocity, zero wind, air temperature and density, and propellant temperature. In practice, this standard combination of conditions almost never existed, they varied throughout the day and day to day, and the greater the time of flight, the greater the inaccuracy.
An added complication was the need for survey to accurately fix the coordinates of the gun position and provide accurate orientation for the guns. Of course, targets had to be accurately located, but by , air photo interpretation techniques enabled this, and ground survey techniques could sometimes be used. In , the methods of correcting firing data for the actual conditions were often convoluted, and the availability of data about actual conditions was rudimentary or non-existent, the assumption was that fire would always be ranged adjusted.
British heavy artillery worked energetically to progressively solve all these problems from late onwards, and by early , had effective processes in place for both field and heavy artillery. These processes enabled 'map-shooting', later called 'predicted fire'; it meant that effective fire could be delivered against an accurately located target without ranging.
Nevertheless, the mean point of impact was still some tens of yards from the target-centre aiming point. It was not precision fire, but it was good enough for concentrations and barrages. These processes remain in use into the 21st Century with refinements to calculations enabled by computers and improved data capture about non-standard conditions. The British major-general Henry Hugh Tudor pioneered armour and artillery cooperation at the breakthrough Battle of Cambrai. The improvements in providing and using data for non-standard conditions propellant temperature, muzzle velocity, wind, air temperature, and barometric pressure were developed by the major combatants throughout the war and enabled effective predicted fire.
In the sixty years preceding , this figure was probably as low as 10 percent. The remaining 90 percent fell to small arms, whose range and accuracy had come to rival those of artillery. Bellamy , pp. An estimated 75, French soldiers were casualties of friendly artillery fire in the four years of World War I. Modern artillery is most obviously distinguished by its long range, firing an explosive shell or rocket and a mobile carriage for firing and transport. However, its most important characteristic is the use of indirect fire, whereby the firing equipment is aimed without seeing the target through its sights.
Indirect fire emerged at the beginning of the 20th century and was greatly enhanced by the development of predicted fire methods in World War I. However, indirect fire was area fire; it was and is not suitable for destroying point targets; its primary purpose is area suppression. These relied on laser designation to 'illuminate' the target that the shell homed onto. The introduction of these led to a new issue, the need for very accurate three dimensional target coordinates—the mensuration process.
Weapons covered by the term 'modern artillery' include " cannon " artillery such as howitzer , mortar , and field gun and rocket artillery. Certain smaller-caliber mortars are more properly designated small arms rather than artillery, albeit indirect-fire small arms. This term also came to include coastal artillery which traditionally defended coastal areas against seaborne attack and controlled the passage of ships.
With the advent of powered flight at the start of the 20th century, artillery also included ground-based anti-aircraft batteries. The term "artillery" has traditionally not been used for projectiles with internal guidance systems , preferring the term "missilery", [ citation needed ] though some modern artillery units employ surface-to-surface missiles. Advances in terminal guidance systems for small munitions has allowed large-caliber guided projectiles to be developed, blurring this distinction.
One of the most important roles of logistics is the supply of munitions as a primary type of artillery consumable, their storage ammunition dump , arsenal , magazine and the provision of fuses, detonators and warheads at the point where artillery troops will assemble the charge, projectile, bomb or shell. Fuzes are the devices that initiate an artillery projectile, either to detonate its high explosive HE filling or eject its cargo illuminating flare or smoke canisters being examples.
The official military spelling is "fuze". Most artillery fuzes are nose fuzes. At least one nuclear shell and its non-nuclear spotting version also used a multi-deck mechanical time fuze fitted into its base. Impact fuzes were, and in some armies remain, the standard fuze for HE projectiles. Their default action is normally 'superquick', some have had a 'graze' action which allows them to penetrate light cover and others have 'delay'. Delay fuzes allow the shell to penetrate the ground before exploding.
Armor- or concrete-piercing fuzes are specially hardened. During World War I and later, ricochet fire with delay or graze fuzed HE shells, fired with a flat angle of descent, was used to achieve airburst. HE shells can be fitted with other fuzes. Airburst fuzes usually have a combined airburst and impact function. However, until the introduction of proximity fuzes , the airburst function was mostly used with cargo munitions—for example, shrapnel, illumination, and smoke. The larger calibers of anti-aircraft artillery are almost always used airburst. Airburst fuzes have to have the fuze length running time set on them.
This is done just before firing using either a wrench or a fuze setter pre-set to the required fuze length. Early airburst fuzes used igniferous timers which lasted into the second half of the 20th century. Mechanical time fuzes appeared in the early part of the century. These required a means of powering them. The Thiel mechanism used a spring and escapement i. From about , electronic time fuzes started replacing mechanical ones for use with cargo munitions. Proximity fuzes have been of two types: The former was not very successful and seems only to have been used with British anti-aircraft artillery 'unrotated projectiles' rockets in World War II.
Radar proximity fuzes were a big improvement over the mechanical time fuzes which they replaced. Mechanical time fuzes required an accurate calculation of their running time, which was affected by non-standard conditions. With HE requiring a burst 20 to 30 feet 9. Accurate running time was less important with cargo munitions that burst much higher.
Their ground use was delayed for fear of the enemy recovering 'blinds' artillery shells which failed to detonate and copying the fuze. The first proximity fuzes were designed to detonate about 30 feet 9. These air-bursts are much more lethal against personnel than ground bursts because they deliver a greater proportion of useful fragments and deliver them into terrain where a prone soldier would be protected from ground bursts.
However, proximity fuzes can suffer premature detonation because of the moisture in heavy rain clouds. These fuzes have a mechanical timer that switched on the radar about 5 seconds before expected impact, they also detonated on impact. The proximity fuze emerged on the battlefields of Europe in late December They have become known as the U.
Artillery's "Christmas present", and were much appreciated when they arrived during the Battle of the Bulge.
They were also used to great effect in anti-aircraft projectiles in the Pacific against kamikaze as well as in Britain against V-1 flying bombs. Electronic multi-function fuzes started to appear around Using solid-state electronics they were relatively cheap and reliable, and became the standard fitted fuze in operational ammunition stocks in some western armies. The early versions were often limited to proximity airburst, albeit with height of burst options, and impact. Later versions introduced induction fuze setting and testing instead of physically placing a fuze setter on the fuze.
The latest, such as Junghan's DM84U provide options giving, superquick, delay, a choice of proximity heights of burst, time and a choice of foliage penetration depths. A new type of artillery fuze will appear soon. In addition to other functions these offer some course correction capability, not full precision but sufficient to significantly reduce the dispersion of the shells on the ground. The projectile is the munition or "bullet" fired downrange. This may or may not be an explosive device.
Traditionally, projectiles have been classified as "shot" or "shell", the former being solid and the latter having some form of "payload". Shells can also be divided into three configurations: The latter is sometimes called the shrapnel configuration. The most modern is base ejection, which was introduced in World War I. Both base and nose ejection are almost always used with airburst fuzes. Bursting shells use various types of fuze depending on the nature of the payload and the tactical need at the time. Most forms of artillery require a propellant to propel the projectile at the target.
Propellant is always a low explosive, this means it deflagrates instead of detonating , as with high explosives. The shell is accelerated to a high velocity in a very short time by the rapid generation of gas from the burning propellant. This high pressure is achieved by burning the propellant in a contained area, either the chamber of a gun barrel or the combustion chamber of a rocket motor.
Until the late 19th century, the only available propellant was black powder. Black powder had many disadvantages as a propellant; it has relatively low power, requiring large amounts of powder to fire projectiles, and created thick clouds of white smoke that would obscure the targets, betray the positions of guns, and make aiming impossible. In , nitrocellulose also known as guncotton was discovered, and the high explosive nitroglycerin was discovered at much the same time.
Nitrocellulose was significantly more powerful than black powder, and was smokeless. Early guncotton was unstable, however, and burned very fast and hot, leading to greatly increased barrel wear. Widespread introduction of smokeless powder would wait until the advent of the double-base powders, which combine nitrocellulose and nitroglycerin to produce powerful, smokeless, stable propellant.
Many other formulations were developed in the following decades, generally trying to find the optimum characteristics of a good artillery propellant; low temperature, high energy, non-corrosive, highly stable, cheap, and easy to manufacture in large quantities. Broadly, modern gun propellants are divided into three classes: Propelling charges for tube artillery can be provided in one of two ways: Generally, anti-aircraft artillery and smaller-caliber up to 3" or This simplifies loading and is necessary for very high rates of fire.
Bagged propellant allows the amount of powder to be raised or lowered, depending on the range to the target. It also makes handling of larger shells easier. Each requires a totally different type of breech to the other. A metal case holds an integral primer to initiate the propellant and provides the gas seal to prevent the gases leaking out of the breech; this is called obturation. With bagged charges, the breech itself provides obturation and holds the primer. In either case, the primer is usually percussion, but electrical is also used, and laser ignition is emerging.
Because field artillery mostly uses indirect fire the guns have to be part of a system that enables them to attack targets invisible to them in accordance with the combined arms plan. All these calculations to produce a quadrant elevation or range and azimuth were done manually using instruments, tablulated, data of the moment, and approximations until battlefield computers started appearing in the s and s. While some early calculators copied the manual method typically substituting polynomials for tabulated data , computers use a different approach. They simulate a shell's trajectory by 'flying' it in short steps and applying data about the conditions affecting the trajectory at each step.
This simulation is repeated until it produces a quadrant elevation and azimuth that lands the shell within the required 'closing' distance of the target coordinates. Supply of artillery ammunition has always been a major component of military logistics. Up until World War I some armies made artillery responsible for all forward ammunition supply because the load of small arms ammunition was trivial compared to artillery. Different armies use different approaches to ammunition supply, which can vary with the nature of operations.
Differences include where the logistic service transfers artillery ammunition to artillery, the amount of ammunition carried in units and extent to which stocks are held at unit or battery level. A key difference is whether supply is 'push' or 'pull'. In the former the 'pipeline' keeps pushing ammunition into formations or units at a defined rate. In the latter units fire as tactically necessary and replenish to maintain or reach their authorised holding which can vary , so the logistic system has to be able to cope with surge and slack. Artillery types can be categorised in several ways, for example by type or size of weapon or ordnance, by role or by organizational arrangements.
The types of cannon artillery are generally distinguished by the velocity at which they fire projectiles. Modern field artillery can also be split into two other subcategories: As the name suggests, towed artillery has a prime mover, usually an artillery tractor or truck, to move the piece, crew, and ammunition around.
Close air support
Towed artillery is in some cases equipped with an APU for small displacements. Self-propelled artillery is permanently mounted on a carriage or vehicle with room for the crew and ammunition and is thus capable of moving quickly from one firing position to another, both to support the fluid nature of modern combat and to avoid counter-battery fire.
It includes mortar carrier vehicles, many of which allow the mortar to be removed from the vehicle and be used dismounted, potentially in terrain in which the vehicle cannot navigate, or in order to avoid detection. At the beginning of the modern artillery period, the late 19th century, many armies had three main types of artillery, in some case they were sub-branches within the artillery branch in others they were separate branches or corps.
There were also other types excluding the armament fitted to warships:. After World War I many nations merged these different artillery branches, in some cases keeping some as sub-branches. Naval artillery disappeared apart from that belonging to marines. However, two new branches of artillery emerged during that war and its aftermath, both used specialised guns and a few rockets and used direct not indirect fire, in the s and s both started to make extensive use of missiles:.
However, the general switch by artillery to indirect fire before and during World War I led to a reaction in some armies.
CiteSeerX — Fire for Effect: Field Artillery and Close Air Support
The result was accompanying or infantry guns. These were usually small, short range guns, that could be easily man-handled and used mostly for direct fire but some could use indirect fire. Some were operated by the artillery branch but under command of the supported unit. In World War II they were joined by self-propelled assault guns, although other armies adopted infantry or close support tanks in armoured branch units for the same purpose, subsequently tanks generally took on the accompanying role.
The three main types of artillery "gun" are guns, howitzers, and mortars. During the 20th century, guns and howitzers have steadily merged in artillery use, making a distinction between the terms somewhat meaningless. The term "cannon" is a United States generic term that includes guns, howitzers, and mortars; it is not used in other English speaking armies.
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These three criteria give eight possible combinations, of which guns and howitzers are but two. However, modern "howitzers" have higher velocities and longer barrels than the equivalent "guns" of the first half of the 20th century. The latter often led to fixed ammunition where the projectile is locked to the cartridge case.
There is no generally accepted minimum muzzle velocity or barrel length associated with a gun. Howitzers also have a choice of charges, meaning that the same elevation angle of fire will achieve a different range depending on the charge used. They have rifled bores, lower muzzle velocities and shorter barrels than equivalent guns. All this means they can deliver fire with a steep angle of descent. Because of their multi-charge capability, their ammunition is mostly separate loading the projectile and propellant are loaded separately.
That leaves six combinations of the three criteria, some of which have been termed gun howitzers. A term first used in the s when howitzers with a relatively high maximum muzzle velocities were introduced, it never became widely accepted, most armies electing to widen the definition of "gun" or "howitzer".
The modern mortar originated in World War I and there were several patterns. The projectile with its integral propelling charge was dropped down the barrel from the muzzle to hit a fixed firing pin. Since that time, a few mortars have become rifled and adopted breech loading. There are other recognized typifying characteristics for artillery. One such characteristic is the type of obturation used to seal the chamber and prevent gases escaping through the breech. This may use a metal cartridge case that also holds the propelling charge, a configuration called "QF" or "quickfiring" by some nations.
The alternative does not use a metal cartridge case, the propellant being merely bagged or in combustible cases with the breech itself providing all the sealing. This is called "BL" or "breech loading" by some nations. A second characteristic is the form of propulsion. Modern equipment can either be towed or self-propelled SP. A towed gun fires from the ground and any inherent protection is limited to a gun shield. Towing by horse teams lasted throughout World War II in some armies, but others were fully mechanized with wheeled or tracked gun towing vehicles by the outbreak of that war.
The size of a towing vehicle depends on the weight of the equipment and the amount of ammunition it has to carry. A variation of towed is portee, where the vehicle carries the gun which is dismounted for firing. Mortars are often carried this way. A mortar is sometimes carried in an armored vehicle and can either fire from it or be dismounted to fire from the ground. Since the early s it has been possible to carry lighter towed guns and most mortars by helicopter.
Even before that, they were parachuted or landed by glider from the time of the first airborne trials in the USSR in the s. In an SP equipment, the gun is an integral part of the vehicle that carries it. They are mostly tracked vehicles, but wheeled SPs started to appear in the s. Some SPs have no armor and carry little or no ammunition. Armoured SPs usually carry a useful ammunition load.
Early armoured SPs were mostly a "casemate" configuration, in essence an open top armored box offering only limited traverse. However, most modern armored SPs have a full enclosed armored turret, usually giving full traverse for the gun. Many SPs cannot fire without deploying stabilizers or spades, sometimes hydraulic. A few SPs are designed so that the recoil forces of the gun are transferred directly onto the ground through a baseplate. A few towed guns have been given limited self-propulsion by means of an auxiliary engine.
Two other forms of tactical propulsion were used in the first half of the 20th century: Railways or transporting the equipment by road, as two or three separate loads, with disassembly and re-assembly at the beginning and end of the journey. Railway artillery took two forms, railway mountings for heavy and super-heavy guns and howitzers and armored trains as "fighting vehicles" armed with light artillery in a direct fire role.
Disassembled transport was also used with heavy and super heavy weapons and lasted into the s. A third form of artillery typing is to classify it as "light", "medium", "heavy" and various other terms. It appears to have been introduced in World War I, which spawned a very wide array of artillery in all sorts of sizes so a simple categorical system was needed. Some armies defined these categories by bands of calibers. Different bands were used for different types of weapons—field guns, mortars, anti-aircraft guns and coastal guns.
List of countries in order of amount of artillery: Artillery is used in a variety of roles depending on its type and caliber. The general role of artillery is to provide fire support —"the application of fire, coordinated with the manoeuvre of forces to destroy, neutralize or suppress the enemy". The italicised terms are NATO's. Unlike rockets, guns or howitzers as some armies still call them and mortars are suitable for delivering close supporting fire. However, they are all suitable for providing deep supporting fire although the limited range of many mortars tends to exclude them from the role.
Their control arrangements and limited range also mean that mortars are most suited to direct supporting fire. Guns are used either for this or general supporting fire while rockets are mostly used for the latter. However, lighter rockets may be used for direct fire support. These rules of thumb apply to NATO armies. Modern mortars , because of their lighter weight and simpler, more transportable design, are usually an integral part of infantry and, in some armies, armor units.
This means they generally do not have to concentrate their fire so their shorter range is not a disadvantage. Some armies also consider infantry operated mortars to be more responsive than artillery, but this is a function of the control arrangements and not the case in all armies. However, mortars have always been used by artillery units and remain with them in many armies, including a few in NATO.
In NATO armies artillery is usually assigned a tactical mission that establishes its relationship and responsibilities to the formation or units it is assigned to. The standard terms are: These tactical missions are in the context of the command authority: In NATO direct support generally means that the directly supporting artillery unit provides observers and liaison to the manoeuvre troops being supported, typically an artillery battalion or equivalent is assigned to a brigade and its batteries to the brigade's battalions.
However, some armies achieve this by placing the assigned artillery units under command of the directly supported formation. Nevertheless, the batteries' fire can be concentrated onto a single target, as can the fire of units in range and with the other tactical missions. There are several dimensions to this subject. The first is the notion that fire may be against an opportunity target or may be prearranged. If it is the latter it may be either on-call or scheduled. Prearranged targets may be part of a fire plan. Fire may be either observed or unobserved , if the former it may be adjusted , if the latter then it has to be predicted.
Observation of adjusted fire may be directly by a forward observer or indirectly via some other target acquisition system. These purposes have existed for most of the 20th century, although their definitions have evolved and will continue to do so, lack of suppression in counterbattery is an omission.
Security is continuous throughout advance party operations. Once a location is determined to be safe, the advance party prepares the position for eventual howitzer emplacement. This consists of several procedures, such as escorting each howitzer to its prepared position, setting up communications, providing the unit with its initial azimuth of fire, and providing each gun with an initial deflection.
This entire process is covered in U. Army Field Manual Chapter 2. Modern day FOs are also [ citation needed ] trained in the rudiments of calling close air support , naval gunfire support and other indirect fire weapons systems. Using a standardized format, the FO sends either an absolute position or a position relative to another point, a brief target description, a recommended munition to use, and any special instructions, such as "danger close" warning that friendly troops are close to the target, requiring extra precision from the guns.
Firing begins with an adjustment phase where only a single gun fires, and if the rounds are not accurate, the FO will issue instructions to adjust fire in four dimensions three spatial and one temporal. When the degree of accuracy is acceptable, the FO will then typically call " fire for effect ", unless the objective of that fire mission is something other than suppression or destruction of the target. The forward observer can also be airborne; one of the original roles of aircraft in the military was airborne artillery spotting [ citation needed ].
The fire direction center concept was developed at the Field Artillery School at Ft. Sill, Oklahoma , during the s under the leadership of its Director of Gunnery, Carlos Brewer  and his instructors, who abandoned massing fire by a described terrain feature or grid coordinate reference. They introduced a firing chart, adopted the practice of locating battery positions by survey, and designated targets with reference to the base point on the chart.
In the spring of , the Gunnery Department successfully demonstrated massing battalion fire using this method, which was used extensively by field artillery during World War II. Typically, there is one FDC for a battery of six guns, in a light division. In a typical heavy division configuration, there exists two FDC elements capable of operating two four gun sections, also known as a split battery.
The FDC computes firing data, fire direction , for the guns. The process consists of determining the precise target location based on the observer's location if needed, then computing range and direction to the target from the guns' location. This data can be computed manually, using special protractors and slide rules with precomputed firing data. Corrections can be added for conditions such as a difference between target and howitzer altitudes, propellant temperature, atmospheric conditions, and even the curvature and rotation of the Earth. In most cases, some corrections are omitted, sacrificing accuracy for speed.
In recent decades, FDCs have become computerized, allowing for much faster and more accurate computation of firing data. The FDC will transmit a warning order to the guns, followed by orders specifying the type of ammunition, fuze setting and propelling charge, bearing, elevation, and the method of adjustment or orders for fire for effect FFE. Elevation vertical direction and bearing orders are specified in mils , and any special instructions, such as to wait for the observer's command to fire relayed through the FDC.
The crews load the howitzers and traverse and elevate the tube to the required point, using either hand cranks usually on towed guns or hydraulics on self-propelled models. FDCs also exist in the next-higher parent battalion that "owns" 2—4 artillery batteries. The rule is "silence is consent", meaning that if the lower unit does not hear a "cancel the mission" don't shoot or even a "check firing" cease firing order from the higher monitoring unit, then the mission goes on.
Higher-level units monitor their subordinate unit's missions for both active as well as passive purposes. Artillery gunners are taught how to use direct fire to engage a target such as mounted or dismounted troops attacking them. In such a case, however, the artillery crews are able to see what they are shooting at. With indirect fire , in normal artillery missions, the crews manning the guns cannot see their target directly, or observers are doing that work for them. Suribachi , the actual adjustment of their fire was accomplished by forward observers directly supporting and attached to infantry units, because they were in the position not only to see the enemy but to prevent friendly fire incidents and to coordinate shelling the Japanese with their infantry unit's movements.
From Wikipedia, the free encyclopedia. Gabriel and Karen S. Strategic Studies Institute, U. Retrieved September 9,