Earliest use The use of balloons by the U.S. Army during the American Civil War compelled the Confederates to develop methods of combating them. These included the use of artillery, small arms, and saboteurs. They were unsuccessful, and internal politics led the United States Army's
Balloon Corps to be disbanded mid-war. The Confederates experimented with balloons as well. Turks carried out the first ever anti-airplane operation in history during the
Italo-Turkish War. Although lacking anti-aircraft weapons, they were the first to shoot down an airplane by rifle fire. The first aircraft to crash in a war was the one of Lieutenant Piero Manzini, shot down on 25 August 1912. The earliest known use of weapons specifically made for the anti-aircraft role occurred during the
Franco-Prussian War of 1870. After the
disaster at Sedan,
Paris was besieged and French troops outside the city started an attempt at communication via
balloon. Gustav
Krupp mounted a modified 1-pounder (37 mm) gun – the
Ballonabwehrkanone (Balloon defence cannon) or
BaK — on top of a horse-drawn carriage for the purpose of shooting down these balloons. File:Canon antiballons.JPG|
Ballonabwehrkanone by Krupp File:Ballonkanone.JPG|
Ballonabwehrkanone by Krupp File:Balloon gun on Prussian corvette Nymphe 1872 NLV.jpeg|
Ballonabwehrkanone on the Prussian corvette
Nymphe 1872 File:Becker Flab 1917.jpg|20 mm Becker-Oerlikon Model 1917 AA-gun By the early 20th century balloon, or airship, guns, for land and naval use were attracting attention. Various types of ammunition were proposed, high explosive, incendiary, bullet-chains, rod bullets and shrapnel. The need for some form of tracer or smoke trail was articulated. Fuzing options were also examined, both impact and time types. Mountings were generally pedestal type but could be on field platforms. Trials were underway in most countries in Europe but only Krupp, Erhardt,
Vickers Maxim, and
Schneider had published any information by 1910. Krupp's designs included adaptations of their 65 mm 9-pounder, a 75 mm 12-pounder, and even a 105 mm gun. Erhardt also had a 12-pounder, while Vickers Maxim offered a 3-pounder and Schneider a 47 mm. The French balloon gun appeared in 1910, it was an 11-pounder but mounted on a vehicle, with a total uncrewed weight of two tons. However, since balloons were slow moving, sights were simple. But the challenges of faster moving aeroplanes were recognised. By 1913 only France and Germany had developed field guns suitable for engaging balloons and aircraft and addressed issues of military organisation. Britain's Royal Navy would soon introduce the
QF 3-inch and
QF 4-inch AA guns and also had
Vickers 1-pounder quick firing "pom-poms" that could be used in various mountings. The first US anti-aircraft cannon was a 1-pounder concept design by
Admiral Twining in 1911 to meet the perceived threat of airships, that eventually was used as the basis for the US Navy's first operational anti-aircraft cannon: the
3-inch/23 caliber gun.
First World War near Paris. From the journal
Horseless Age, 1916. On 30 September 1915, troops of the
Serbian Army observed three enemy aircraft approaching
Kragujevac. Soldiers fired at them with shotguns and machine-guns but failed to prevent them from dropping 45 bombs over the city, hitting military installations, the railway station and many other, mostly civilian, targets in the city. During the bombing raid, private
Radoje Ljutovac fired his cannon at the enemy aircraft and successfully shot one down. It crashed in the city and both pilots died from their injuries. The cannon Ljutovac used was not designed as an anti-aircraft gun; it was a slightly modified Turkish cannon captured during the
First Balkan War in 1912. This was the first occasion in military history that a military aircraft was shot down with
ground-to-air artillery fire. The British recognised the need for anti-aircraft capability a few weeks before World War I broke out; on 8 July 1914, the
New York Times reported that the British government had decided to "dot the coasts of the British Isles with a series of towers, each armed with two quick-firing guns of special design," while "a complete circle of towers" was to be built around "naval installations" and "at other especially vulnerable points". By December 1914 the
Royal Naval Volunteer Reserve (RNVR) was manning AA guns and searchlights assembled from various sources at some nine ports. The
Royal Garrison Artillery (RGA) was given responsibility for AA defence in the field, using motorised two-gun sections. The first were formally formed in November 1914. Initially they used
QF 1-pounder "pom-pom"s (37 mm versions of the
Maxim Gun). All armies soon deployed AA guns often based on their smaller field pieces, notably the French 75 mm and Russian 76.2 mm, typically simply propped up on some sort of embankment to get the muzzle pointed skyward. The
British Army adopted the 13-pounder quickly producing new mountings suitable for AA use, the
13-pounder QF 6 cwt Mk III was issued in 1915. It remained in service throughout the war but 18-pounder guns were lined down to take the 13-pounder shell with a larger cartridge producing the
13-pounder QF 9 cwt and these proved much more satisfactory. However, in general, these ad hoc solutions proved largely useless. With little experience in the role, no means of measuring target, range, height or speed the difficulty of observing their shell bursts relative to the target gunners proved unable to get their fuse setting correct and most rounds burst well below their targets. The exception to this rule was the guns protecting spotting balloons, in which case the altitude could be accurately measured from the length of the cable holding the balloon. The first issue was ammunition. Before the war it was recognised that ammunition needed to explode in the air. Both high explosive (HE) and
shrapnel were used, mostly the former. Airburst fuses were either igniferious (based on a burning fuse) or mechanical (clockwork). Igniferious fuses were not well suited for anti-aircraft use. The fuse length was determined by time of flight, but the burning rate of the gunpowder was affected by altitude. The British pom-poms had only contact-fused ammunition.
Zeppelins, being hydrogen-filled balloons, were targets for incendiary shells and the British introduced these with airburst fuses, both shrapnel type-forward projection of incendiary "pot" and base ejection of an incendiary stream. The British also fitted tracers to their shells for use at night. Smoke shells were also available for some AA guns, these bursts were used as targets during training. German air attacks on the British Isles increased in 1915 and the AA efforts were deemed somewhat ineffective, so a
Royal Navy gunnery expert, Admiral Sir
Percy Scott, was appointed to make improvements, particularly an integrated AA defence for London. The air defences were expanded with more RNVR AA guns, 75 mm and 3-inch, the pom-poms being ineffective. The naval 3-inch was also adopted by the army, the
QF 3-inch 20 cwt (76 mm), a new field mounting was introduced in 1916. Since most attacks were at night, searchlights were soon used, and acoustic methods of detection and locating were developed. By December 1916 there were 183 AA sections defending Britain (most with the 3-inch), 74 with the BEF in France and 10 in the Middle East. AA gunnery was a difficult business. The problem was of successfully aiming a shell to burst close to its target's future position, with various factors affecting the shells' predicted trajectory. This was called deflection gun-laying, where "off-set" angles for range and elevation were set on the gunsight and updated as their target moved. In this method, when the sights were on the target, the barrel was pointed at the target's future position. Range and height of the target determined fuse length. The difficulties increased as aircraft performance improved. The British dealt with range measurement first, when it was realised that range was the key to producing a better fuse setting. This led to the
height/range finder (HRF), the first model being the
Barr & Stroud UB2, a two-metre
optical coincident rangefinder mounted on a tripod. It measured the distance to the target and the elevation angle, which together gave the height of the aircraft. These were complex instruments and various other methods were also used. The HRF was soon joined by the height/fuse indicator (HFI), this was marked with elevation angles and height lines overlaid with fuse length curves, using the height reported by the HRF operator, the necessary fuse length could be read off. However, the problem of deflection settings — "aim-off" — required knowing the rate of change in the target's position. Both France and the UK introduced tachymetric devices to track targets and produce vertical and horizontal deflection angles. The French Brocq system was electrical; the operator entered the target range and had displays at guns; it was used with their 75 mm. The British Wilson-Dalby gun director used a pair of trackers and mechanical tachymetry; the operator entered the fuse length, and deflection angles were read from the instruments. By the start of
World War I, the 77 mm had become the standard German weapon, and came mounted on a large traverse that could be easily transported on a wagon. Krupp 75 mm guns were supplied with an optical sighting system that improved their capabilities. The German Army also adapted a revolving cannon that came to be known to Allied fliers as the "
flaming onion" from the shells in flight. This gun had five barrels that quickly launched a series of 37 mm artillery shells. As aircraft started to be used against ground targets on the battlefield, the AA guns could not be traversed quickly enough at close targets and, being relatively few, were not always in the right place (and were often unpopular with other troops), so changed positions frequently. Soon the forces were adding various machine-gun based weapons mounted on poles. These short-range weapons proved more deadly, and the "
Red Baron" is believed to have been shot down by an anti-aircraft
Vickers machine gun. When the war ended, it was clear that the increasing capabilities of aircraft would require better means of acquiring targets and aiming at them. Nevertheless, a pattern had been set: anti-aircraft warfare would employ heavy weapons to attack high-altitude targets and lighter weapons for use when aircraft came to lower altitudes. was a mechanical computer.
Interwar years World War I demonstrated that aircraft could be an important part of the battlefield, but in some nations it was the prospect of strategic air attack that was the main issue, presenting both a threat and an opportunity. The experience of four years of air attacks on London by Zeppelins and
Gotha G.V bombers had particularly influenced the British and was one of if not the main driver for forming an independent air force. As the capabilities of aircraft and their engines improved it was clear that their role in future war would be even more critical as their range and weapon load grew. However, in the years immediately after World War I, the prospect of another major war seemed remote, particularly in Europe, where the most militarily capable nations were, and little financing was available. Four years of war had seen the creation of a new and technically demanding branch of military activity. Air defence had made huge advances, albeit from a very low starting point. However, it was new and often lacked influential 'friends' in the competition for a share of limited defence budgets. Demobilisation meant that most AA guns were taken out of service, leaving only the most modern. However, there were lessons to be learned. In particular the British, who had had AA guns in most theatres in action in daylight and used them against night attacks at home. Furthermore, they had also formed an
Anti-Aircraft Experimental Section during the war and accumulated large amounts of data that was subjected to extensive analysis. As a result, they published the two-volume
Textbook of Anti-Aircraft Gunnery in 1924–1925. It included five key recommendations for HAA equipment: • Shells of improved ballistic shape with HE fillings and mechanical time fuses • Higher rates of fire assisted by automation • Height finding by long-base optical instruments • Centralised control of fire on each gun position, directed by tachymetric instruments incorporating the facility to apply corrections of the moment for meteorological and wear factors • More accurate sound-location for the direction of searchlights and to provide plots for barrage fire Two assumptions underpinned the British approach to HAA fire; first, aimed fire was the primary method and this was enabled by predicting gun data from visually tracking the target and having its height. Second, that the target would maintain a steady course, speed and height. This HAA was to engage targets up to . Mechanical time fuses were required because the speed of powder burning varied with height, so fuse length was not a simple function of time of flight. Automated fire ensured a constant rate of fire that made it easier to predict where each shell should be individually aimed. In 1925 the British adopted a new instrument developed by Vickers. It was a mechanical
analogue computer – the Predictor AA No 1. Given the target height, its operators tracked the target and the predictor produced bearing, quadrant elevation and fuse setting. These were passed electrically to the guns, where they were displayed on repeater dials to the layers who "matched pointers" (target data and the gun's actual data) to lay the guns. This system of repeater electrical dials built on the arrangements introduced by British coast artillery in the 1880s, and coast artillery was the background of many AA officers. Similar systems were adopted in other countries and for example the later Sperry M3A3 in the US, was also used by Britain as the Predictor AA No 2. Height finders were also increasing in size; in Britain, the optical base World War I
Barr & Stroud UB 2
stereoscopic rangefinder was replaced by the optical base UB 7 and the base UB 10 (only used on static AA sites). Goertz in Germany and Levallois in France produced instruments. However, in most countries the main effort in HAA guns until the mid-1930s was improving existing ones, although various new designs were on drawing boards. From the early 1930s eight countries
developed radar; these developments were sufficiently advanced by the late 1930s for development work on
sound-locating acoustic devices to be generally halted, although equipment was retained. Furthermore, in Britain the volunteer
Observer Corps formed in 1925 provided a network of observation posts to report hostile aircraft flying over Britain. Initially radar was used for airspace surveillance to detect approaching hostile aircraft. However, the German
Würzburg radar put into use in 1940 was capable of providing data suitable for controlling AA guns, and the British
Radar, Gun Laying, Mark I, was designed to be used on AA gun positions and was in use by 1939. The
Treaty of Versailles prevented Germany having AA weapons, and for example, the Krupps designers joined Bofors in Sweden. Some World War I guns were retained and some covert AA training started in the late 1920s. Germany introduced the 8.8 cm FlaK 18 in 1933, the 36 and 37 models followed with various improvements, but ballistic performance was unchanged. In the late 1930s the
10.5 cm FlaK 38 appeared, soon followed by the 39; this was designed primarily for static sites but had a mobile mounting, and the unit had 220 V 24 kW generators. In 1938 design started on the
12.8 cm FlaK. Britain had successfully tested a new 3.6-inch gun, in 1918. In 1928 a gun became the preferred solution, but it took six years to gain funding. Production of the
QF 3.7-inch gun began in 1937; this gun was used on mobile carriages with the field army and transportable guns on fixed mountings for static positions. At the same time the Royal Navy adopted a new
4.5-inch (113 mm) gun in a twin turret, which the army adopted in simplified single-gun mountings for static positions, mostly around ports where naval ammunition was available. The performance of the new guns was limited by their standard fuse No 199, with a 30-second running time, although a new mechanical time fuse giving 43 seconds was nearing readiness. In 1939 a machine fuse setter was introduced to eliminate manual fuse setting. The US ended World War I with two 3-inch AA guns and improvements were developed throughout the inter-war period. However, in 1924 work started on a new 105 mm static mounting AA gun, but only a few were produced by the mid-1930s because by this time work had started on the 90 mm AA gun, with mobile carriages and static mountings able to engage air, sea and ground targets. The M1 version was approved in 1940. During the 1920s there was some work on a 4.7-inch which lapsed, but revived in 1937, leading to a new gun in 1944. While HAA and its associated target acquisition and fire control was the primary focus of AA efforts, low-level close-range targets remained and by the mid-1930s were becoming an issue. Until this time the British, at RAF insistence, continued their use of World War I machine guns, and introduced twin MG mountings for AAAD. The army was forbidden from considering anything larger than .50-inch. However, in 1935 their trials showed that the minimum effective round was an impact-fused 2 lb HE shell. The following year they decided to adopt the
Bofors 40 mm and a
twin barrel Vickers 2-pounder (40 mm) on a modified naval mount. The air-cooled Bofors was vastly superior for land use, being much lighter than the water-cooled "pom-pom", and UK production of the Bofors 40 mm was licensed. The Predictor AA No 3, as the
Kerrison Predictor was officially known, was introduced with it. The 40 mm Bofors had become available in 1931. In the late 1920s the
Swedish Navy had ordered the development of a 40 mm naval anti-aircraft gun from the Bofors company. It was light, rapid-firing and reliable, and a mobile version on a four-wheel carriage was soon developed. Known simply as the
40 mm, it was adopted by some 17 different nations just before World War II and is still in use today in some applications such as on coastguard frigates. Rheinmetall in Germany developed an automatic 20 mm in the 1920s and Oerlikon in Switzerland had acquired the patent to an automatic 20 mm gun designed in Germany during World War I. Germany introduced the rapid-fire
2 cm FlaK 30 and later in the decade it was redesigned by Mauser-Werke and became the 2 cm FlaK 38. Nevertheless, while 20 mm was better than a machine gun and mounted on a very small trailer made it easy to move, its effectiveness was limited. Germany therefore added a 3.7 cm. The first, the
3.7 cm FlaK 18 developed by Rheinmetall in the early 1930s, was basically an enlarged 2 cm FlaK 30. It was introduced in 1935 and production stopped the following year. A redesigned gun 3.7 cm FlaK 36 entered service in 1938, it too had a two-wheel carriage. However, by the mid-1930s the Luftwaffe realised that there was still a coverage gap between 3.7 cm and 8.8 cm guns. They started development of a 5 cm gun on a four-wheel carriage. After World War I the US Army started developing a dual-role (AA/ground) automatic 37 mm cannon, designed by
John M. Browning. It was standardised in 1927 as the T9 AA cannon, but trials quickly revealed that it was worthless in the ground role. However, while the shell was a bit light (well under 2 lbs) it had a good effective ceiling and fired 125 rounds per minute; an AA carriage was developed and it entered service in 1939 as the
37 mm gun M1. It proved prone to jamming, and was eventually replaced in AA units by the Bofors 40 mm. The Bofors had attracted attention from the US Navy, but none were acquired before 1939. Also, in 1931 the US Army worked on a mobile anti-aircraft machine mount on the back of a heavy truck having four .30 calibre water-cooled machine guns and an optical director. It proved unsuccessful and was abandoned. The USSR introduced a new 76 mm
M1931 in 1937, an 85 mm
M1938 and developed the
37 mm M1939 (61-K), which appears to have been copied from the Bofors 40 mm. A Bofors 25 mm, essentially a scaled down 40 mm, was also copied as the
25 mm M1939. During the 1930s solid-fuel rockets were under development in the Soviet Union and Britain. In Britain the interest was for anti-aircraft fire, it quickly became clear that guidance would be required for precision. However, rockets, or "
Unrotated Projectiles" as they were called, could be used for anti-aircraft barrages. A two-inch rocket using HE or wire obstacle warheads – the
Z Battery – was introduced first to deal with low-level or dive bombing attacks on smaller targets such as airfields. The three-inch was in development at the end of the inter-war period.
Naval aspects WWI had been a war in which air warfare blossomed, but had not matured to the point of being a real threat to naval forces. The prevailing assumption was that a few relatively small caliber naval guns could manage to keep enemy aircraft beyond a range where harm might be expected. In 1939 radio controlled
target drones became available to the US Navy in quantity allowing a more realistic testing of existing anti-aircraft suites against actual flying and manoeuvring targets. The results were sobering to an unexpected degree. The United States was still emerging from the effects of the
Great Depression and funds for the military had been sparse to the degree that 50% of shells used were still powder fused. So rapid was the performance leaps of evolving aircraft that the British
High Angle Control System (HACS) was obsolete and designing a successor very difficult for the British establishment. Electronics would prove to be an enabler for effective anti-aircraft systems and both the US and UK had a growing electronics industry. There is no evidence of other powers using drones in this application at all. It may have caused a major underestimation of the threat and an inflated view of their AA systems.
Second World War flak gun in action against Allied bombers Poland's AA defences were no match for the German attack, and the situation was similar in other European countries. Significant AAW (Anti-Air Warfare) started with the
Battle of Britain in the summer of 1940.
QF 3.7-inch AA guns provided the backbone of the ground-based AA defences, although initially significant numbers of
QF 3-inch 20 cwt were also used. The Army's Anti-aircraft command, which was under operational command of
RAF Fighter Command within Air Defence GB, grew to 12 AA divisions in three AA corps.
Bofors 40 mm guns entered service in increasing numbers. In addition, the RAF regiment was formed in 1941 with responsibility for airfield air defence, eventually with Bofors 40 mm as their main armament. Fixed AA defences, using HAA and LAA, were established by the Army in key overseas places, notably
Malta,
Suez Canal and
Singapore. While the 3.7-inch was the main HAA gun in fixed defences and the only mobile HAA gun with the field army, the
QF 4.5-inch gun, manned by artillery, was used in the vicinity of naval ports and made use of the naval ammunition supply. The 4.5-inch at Singapore had the first success in shooting down Japanese bombers. Mid war
QF 5.25-inch naval guns started being emplaced in some permanent sites around London. This gun was also deployed in dual-role coast defence/AA positions. anti-aircraft gun in WWII Germany's high-altitude needs were originally going to be filled by a 75 mm gun from
Krupp, designed in collaboration with their Swedish counterpart
Bofors, but the specifications were later amended to require much higher performance. In response Krupp's engineers presented a new 88 mm design, the
FlaK 36. First used in Spain during the
Spanish Civil War, the gun proved to be one of the best anti-aircraft guns in the world, as well as particularly deadly against light, medium, and even early heavy tanks. After the
Dambusters raid in 1943 an entirely new system was developed that was required to knock down any low-flying aircraft with a single hit. The first attempt to produce such a system used a 50 mm gun, but this proved inaccurate and a new 55 mm gun replaced it. The system used a centralised control system including both search and targeting
radar, which calculated the aim point for the guns after considering windage and ballistics, and then sent electrical commands to the guns, which used
hydraulics to point themselves at high speeds. Operators simply fed the guns and selected the targets. This system, modern even by today's standards, was in late development when the war ended.
Consolidated B-24 Liberator hit by flak over Italy, 10 April 1945 The British had already arranged licence building of the Bofors 40 mm, and introduced these into service. These had the power to knock down aircraft of any size, yet were light enough to be mobile and easily swung. The gun became so important to the British war effort that they even produced a movie,
The Gun, that encouraged workers on the assembly line to work harder. The Imperial measurement production drawings the British had developed were supplied to the Americans who produced their own (unlicensed) copy of the 40 mm at the start of the war, moving to licensed production in mid-1941. Service trials demonstrated another problem however: that ranging and tracking the new high-speed targets was almost impossible. At short range, the apparent target area is relatively large, the trajectory is flat and the time of flight is short, allowing to correct lead by watching the tracers. At long range, the aircraft remains in firing range for a long time, so the necessary calculations can, in theory, be done by slide rules—though, because small errors in distance cause large errors in shell fall height and detonation time, exact ranging is crucial. For the ranges and speeds that the Bofors worked at, neither answer was good enough. gun in London in 1939 The solution was
automation, in the form of a mechanical computer, the
Kerrison Predictor. Operators kept it pointed at the target, and the Predictor then calculated the proper aim point automatically and displayed it as a pointer mounted on the gun. The gun operators simply followed the pointer and loaded the shells. The Kerrison was fairly simple, but it pointed the way to future generations that incorporated radar, first for ranging and later for tracking. Similar predictor systems were introduced by Germany during the war, also adding radar ranging as the war progressed. A plethora of anti-aircraft gun systems of smaller calibre was available to the German Wehrmacht combined forces, and among them the 1940-origin
Flakvierling quadruple-20 mm-
autocannon-based anti-aircraft weapon system was one of the most often-seen weapons, seeing service on both land and sea. The similar
Allied smaller-calibre air-defence weapons of the American forces were also quite capable. Their needs could cogently be met with smaller-calibre ordnance beyond using the usual singly-mounted
M2 .50 caliber machine gun atop a tank's turret, as four of the ground-used "heavy barrel" (M2HB) guns were mounted together on the American Maxson
M45 Quadmount weapon (as a direct answer to the
Flakvierling), which were often mounted on the back of a
half-track to form the
M16 Multiple Gun Motor Carriage. Although of less power than Germany's 20 mm systems, the typical four or five combat batteries of an Army AAA battalion were often spread many kilometres apart from each other, rapidly attaching and detaching to larger ground combat units to provide welcome defence from enemy aircraft. in an anti-aircraft mount in 1941 AAA battalions were also used to help suppress ground targets. Their larger
90 mm M3 gun would prove, as did the eighty-eight, to make an excellent anti-tank gun as well, and was widely used late in the war in this role. Also available to the Americans at the start of the war was the
120 mm M1 gun stratosphere gun, which was the most powerful AA gun with an impressive altitude capability, however no 120 M1 was ever fired at an enemy aircraft. The 90 mm and 120 mm guns continued to be used into the 1950s. The
United States Navy had also put some thought into the problem, When the US Navy began to rearm in 1939 in many ships the primary short ranged gun was the M2 .50 caliber machine gun. While effective in fighters at 300 to 400 yards this is point blank range in naval anti-aircraft ranges. Production of the Swiss Oerlikon 20 mm had already started to provide protection for the British and this was adopted in exchange for the M2 machine guns. From December 1941 to January 1942, production had risen to not only cover all British requirements but also allowed 812 units to be actually delivered to the US Navy. By the end of 1942 the 20 mm had accounted for 42% of all aircraft destroyed by the US Navy's shipboard AA. However, the King Board had noted that the balance was shifting towards the larger guns used by the fleet. The US Navy had intended to use the British pom-pom, however, the weapon required the use of
cordite which BuOrd had found objectionable for US service. Further investigation revealed that US powders would not work in the pom-pom. Bureau of Ordnance was well aware of the Bofors 40 mm gun. The firm York Safe and Lock was negotiating with Bofors to attain the rights to the air-cooled version of the weapon. At the same time Henry Howard, an engineer, and businessman became aware of it and contacted RADM W. R. Furlong, chief of the Bureau of Ordnance. He ordered the Bofors weapon system to be investigated. York Safe and Lock would be used as the contracting agent. The system had to be redesigned for both the English measurement system and mass production, as the original documents recommended hand fitting parts and drilling to shape. As early as 1928 the US Navy saw the need to replace the .50 caliber machine gun with something heavier. The 1.1"/75 (28 mm) Mark 1 was designed. Placed in quadruple mounts with a 500 rpm rate of fire it would have fit the requirements. However, the gun was suffering teething issues being prone to jamming. While this could have been solved the weight of the system was equal to that of the quad-mount Bofors 40 mm while lacking the range and power that the Bofors provided. The gun was relegated to smaller less vital ships by the end of the war. The
5"/38 naval gun rounded out the US Navy's AA suite. A dual purpose mount, it was used in both the surface and AA roles with great success. Mated with the Mark 37 director and the proximity fuse it could routinely knock drones out of the sky at ranges as far as 13,000 yards.,
40 mm and
20 mm fire directed from
USS New Mexico at a
Kamikaze,
Battle of Okinawa, 1945A 3"/50 MK 22 semiautomatic dual gun was produced but not employed before the end of the war and therefore beyond the scope of this article. However early marks of the 3"/50 were employed in destroyer escorts and on merchant ships. 3″/50
caliber guns (Marks 10, 17, 18, and 20) first entered service in 1915 as a refit to , and were subsequently mounted on many types of ships as the need for anti-aircraft protection was recognised. During World War II, they were the primary gun armament on
destroyer escorts,
patrol frigates,
submarine chasers,
minesweepers, some fleet
submarines, and other auxiliary vessels, and were used as a secondary dual-purpose battery on some other types of ships, including some older battleships. They also replaced the original low-angle
4"/50 caliber guns (Mark 9) on "flush-deck" and s to provide better anti-aircraft protection. The gun was also used on specialist destroyer conversions; the "AVD"
seaplane tender conversions received two guns; the "APD"
high-speed transports, "DM"
minelayers, and
"DMS" minesweeper conversions received three guns, and those retaining destroyer classification received six. s built during
World War II in Vienna The Germans developed massive reinforced-concrete
blockhouses, some more than six stories high, which were known as
Hochbunker 'high bunkers' or "
Flaktürme flak towers, on which they placed anti-aircraft artillery. Those in cities attacked by the Allied land forces became fortresses. Several in
Berlin were some of the last buildings to fall to the Soviets during the
Battle of Berlin in 1945. The British built structures such as the
Maunsell Forts in the
North Sea, the
Thames Estuary and other tidal areas upon which they based guns. After the war most were left to rot. Some were outside territorial waters, and had a second life in the 1960s as platforms for
pirate radio stations, while another became the base of a
micronation, the
Principality of Sealand. bomber emerges from a cloud of flak with its No. 2 engine smoking. Some nations started rocket research before World War II, including for anti-aircraft use. Further research started during the war. The first step was unguided missile systems like the British
2-inch RP and 3-inch, which was fired in large numbers from
Z batteries, and were also fitted to warships. The firing of one of these devices during an air raid is suspected to have caused the
Bethnal Green disaster in 1943. Facing the threat of Japanese
Kamikaze attacks the British and US developed surface-to-air rockets like British
Fairey Stooge or the American
Lark as counter measures, but none of them were ready at the end of the war. The Germans missile research was the most advanced of the war as the Germans put considerable effort in the research and development of rocket systems for all purposes. Among them were several
guided and unguided systems. Unguided systems involved the
Fliegerfaust (literally "aircraft fist") rocket launcher as the first
MANPADS. Guided systems were several sophisticated radio, wire, or radar guided missiles like the
Wasserfall ('waterfall') rocket. Owing to the severe war situation for Germany all of those systems were only produced in small numbers and most of them were only used by training or trial units. ) Another aspect of anti-aircraft defence was the use of
barrage balloons to act as physical obstacle initially to bomber aircraft over cities and later for ground attack aircraft over the
Normandy invasion fleets. The balloon, a simple blimp tethered to the ground, worked in two ways. Firstly, it and the steel cable were a danger to any aircraft that tried to fly among them. Secondly, to avoid the balloons, bombers had to fly at a higher altitude, which was more favourable for the guns. Barrage balloons were limited in application, and had minimal success at bringing down aircraft, being largely immobile and passive defences. The Allies' most advanced technologies were showcased by the anti-aircraft defence against the German
V-1 cruise missiles (V stands for
Vergeltungswaffe, 'retaliation weapon'). The 419th and 601st anti-aircraft gun battalions of the US Army were first allocated to the Folkestone-Dover coast to defend London, and then moved to Belgium to become part of the "Antwerp X" project coordinated from the in
Keerbergen. With the liberation of Antwerp, the port city immediately became the highest priority target, and received the largest number of V-1 and V-2 missiles of any city. The smallest tactical unit of the operation was a gun battery consisting of four 90 mm guns firing shells equipped with a radio
proximity fuse. Incoming targets were acquired and automatically tracked by
SCR-584 radar,. Output from the gun-laying radar was fed to the
M9 Gun Director, an electronic analogue computer to calculate the lead and elevation corrections for the guns. With the help of these three technologies, close to 90% of the V-1 missiles, on track to the defence zone around the port, were destroyed.
Cold War anti-aircraft missile, fired from a
cruiser Post-war analysis demonstrated that even with newest anti-aircraft systems employed by both sides, the vast majority of bombers reached their targets successfully, on the order of 90%. While these figures were undesirable during the war, the advent of the
nuclear bomb considerably altered the acceptability of even a single bomber reaching its target. The developments during World War II continued for a short time into the post-war period as well. In particular the US Army set up a huge air defence network around its larger cities based on radar-guided 90 mm and 120 mm guns. US efforts continued into the 1950s with the 75 mm
Skysweeper system, an almost fully automated system including the radar, computers, power, and auto-loading gun on a single powered platform. The Skysweeper replaced all smaller guns then in use in the Army, notably the 40 mm Bofors. By 1955, the US military deemed the 40 mm Bofors obsolete due to its reduced capability to shoot down jet powered aircraft, and turned to SAM development, with the
Nike Ajax and the
RSD-58. In Europe NATO's Allied Command Europe developed an integrated air defence system, NATO Air Defence Ground Environment (NADGE), that later became the
NATO Integrated Air Defence System. The introduction of the guided missile resulted in a significant shift in anti-aircraft strategy. Although Germany had been desperate to introduce anti-aircraft missile systems, none became operational during World War II. Following several years of post-war development, however, these systems began to mature into viable weapons. The US started an upgrade of their defences using the Nike Ajax missile, and soon the larger anti-aircraft guns disappeared. The same thing occurred in the
USSR after the introduction of their
SA-2 Guideline systems. fireteam practices using a rocket target with a training variant of a
Type 91 Kai MANPADS during an exercise at
Eielson Air Force Base, Alaska, as part of Red Flag – Alaska As this process continued, the missile found itself being used for more and more of the roles formerly filled by guns. First to go were the large weapons, replaced by equally large missile systems of much higher performance. Smaller missiles soon followed, eventually becoming small enough to be mounted on armoured cars and tank chassis. These started replacing, or at least supplanting, similar gun-based
SPAAG systems in the 1960s, and by the 1990s had replaced almost all such systems in modern armies. Man-portable missiles, MANPADS, as they are known today, were introduced in the 1960s and have supplanted or replaced even the smallest guns in most advanced armies. In the 1982
Falklands War, the Argentine armed forces deployed the newest west European weapons including the 35 mm
Oerlikon GDF-002 twin cannon and
Roland missile. The
Rapier missile system was the primary GBAD system, used by both British artillery and RAF regiment, a few brand-new
FIM-92 Stinger were used by British special forces. Both sides also used the
Blowpipe missile. British naval missiles used included
Sea Dart and the older
Sea Slug longer range systems,
SeaCat and the new
Sea Wolf short range systems. Machine guns in AA mountings were used both ashore and afloat.
Post-Cold War During the
2008 South Ossetia war air power faced off against powerful SAM systems, like the 1980s
Buk-M1. In February 2018, an Israeli F-16 fighter was downed in the
Golan Heights province, after it had attacked an Iranian target in Syria. In 2006, Israel also lost a helicopter over Lebanon, shot down by a Hezbollah rocket. == AA warfare systems ==