An anti-aircraft gun (also known as anti-aircraft gun, flak for short , rarely also flak ) is a weapon originally developed during the First World War that is used to defend aircraft. The anti-aircraft cartillery was derived from this , a type of weapon that used machine cannons in addition to these guns . Range and precision (sometimes collectively called combat strength ) could be increased over the years.
After the Second World War , the anti-aircraft guns, whose excessive demands were soon apparent when fighting modern jet aircraft , were increasingly replaced by the newly developed anti-aircraft missiles . Since both types of anti-aircraft weapons have both specific advantages and disadvantages, they are now used in combination whenever possible.
According to current knowledge, the use of special weapons against aircraft took place for the first time in 1870 during the Franco-German War . After the victory of the German army at Sedan , Paris was besieged and the French troops inside the city tried to use balloons to carry messages outside. In order to shoot these balloons, Krupp modified a 3.7 cm gun so that it could be mounted on a horse-drawn wagon, making it more mobile. The successes were moderate - only the Le Daguerre balloon was shot down on November 12, 1870 and the crew captured.
First World War
Italian anti-aircraft gun 102/35 Mod. 1914 on SPA 9000 trucks
German 3.7 cm balloon flak ( Musée Royal de l'Armée )
In Germany, the development of anti-aircraft guns was promoted even before the beginning of the First World War . In 1909, the Krupp company presented a number of variants of their 6.5 cm, 7.5 cm and even 10.5 cm guns for air defense. However, tests soon showed that normal field guns were unsuitable because their projectile speed was too low and the flight path was therefore too curved. In 1913 and 1914, the army undertook target practice on the Baltic Sea with guns of the Krupp and Ehrhardt types, which could be swiveled through 360 ° on pivot mounts . As the main target military tactician saw initially less the enemy plane, but tethered balloons or military airships , hence the term set initially BAK for B allon a bwehr k anone through. It was in May 1916 in Fl ug a bwehr k changed anone.
In other countries it was not believed at the time that airplanes could play an important role in military conflicts, but soon after the outbreak of war the French aviators , who conducted astonishingly accurate artillery strikes with the help of small reconnaissance planes, were taught otherwise. All armies therefore soon used their smaller guns up to about 75 mm against aircraft, which were usually simply jacked up so that the tube pointed towards the sky. The British Army developed a new 3-inch caliber weapon.
In general, however, these ad hoc solutions have proven to be largely ineffective. With no experience in combating air targets and no way of precisely determining the location of their salvos, the artillerymen were overwhelmed, as they could only estimate the target's height. Most of the defensive fire was well below the target. The exception to this rule were the guns, which were supported by reconnaissance balloons. In this case, the height of the target could be determined very accurately by the length of the tether that held the balloon. The Krupp guns were later equipped with an optical aiming system that significantly improved their hit rate, but other armies did not use these techniques for the time being.
When planes were also used for tactical attacks on ground targets, the large guns proved too cumbersome to be aimed at the fast-moving planes. For the time being, the troops used their regular machine guns for air defense , but the development of smaller cannons began very soon; For example, the British introduced an anti-aircraft weapon with ammunition supply via a belt based on a 1 pounder (37 mm) gun. In return, the German army used a rapid-fire 3.7 cm automatic cannon. These short-range weapons proved to be far more accurate. As the war neared its end, it was clear that the ability to shoot down planes would require more serious approaches.
Second World War
The First World War had shown that airspace had become an important part of the battlefield. As the aircraft's capabilities continued to improve , especially with more powerful engines , it became clear that their future role in combat would be much broader than before.
In the early 1930s, most countries developed special anti-aircraft guns. Often several machine guns were combined into one defense gun to increase the firepower. While the British and Americans traditionally had the protection of their fleets in mind, other countries developed the guns to protect ground troops.
Against the background of the so-called Sudeten Crisis, at the end of May 1938, the first time in Germany was concerned with the establishment of a flak zone (West Air Defense Zone) in the hinterland of the West Wall under construction. At the beginning of June 1938, the first orders to build bunkered, fortress-like flak batteries were issued by the German Air Force . The attacking air forces were to be hindered on their flights into the Reich territory and to be forced to flights at altitudes above 6000 meters. It should also pose a serious threat on the return flight. At the beginning of the Second World War, anti- aircraft systems were developed in Germany , which consisted of a control tower and a combat tower, as an increase in the position was necessary in the densely built-up urban area. These included bunkers, including for the civilian population.
A number of new anti-aircraft guns were also developed in Germany, including a 2 cm rapid fire gun for low and a 3.7 cm gun for low and medium heights. In the mid-1930s, the 2 cm gun was already considered too weak against the increasingly faster aircraft, but instead of developing a new gun, Krupp mounted four of these 2 cm guns on a common carriage, which significantly increased the firepower. At the end of the war, the 2 cm cannon was no longer sufficient, but since the 3.7 cm version was only available to a limited extent and a new system based on the 3 cm MK 103 was never widely used, it was possible to open they cannot be waived.
The need for anti-aircraft defense at high altitudes was originally intended to be met by an improved 3-inch design from Krupp, but the catalog of requirements was later changed to require higher performance. Krupp's engineers therefore worked with Bofors in Sweden to develop an 8.8 cm gun, the Flak 18 . The basic development was already completed by the end of the First World War. The Flak 18 had, among other things, a fast, semi-automatic loading system and a separable barrel (the rear part wears more from the ignition taking place there). The cannon, known colloquially as the " eight-eight ", was to become one of the most famous guns of the Second World War. During its first use in the Spanish Civil War , the cannon proved to be one of the best anti-aircraft guns in the world and also particularly effective against tanks . In contrast to many other types, the eight-eight can also be directed below the horizontal , i.e. also shoot "downhill".
Especially when used on the ground, this weapon proved to be the only effective weapon against heavy tanks until the appearance of improved anti-tank guns, and in this role it was known and feared above all by the Allies . Because of its high penetration power , a modified version of the "eight-eight" was built into the Tiger armored vehicle as a combat vehicle cannon . The firing and penetration performance of the anti-aircraft gun was mainly improved by further developing the ammunition and extending the barrel. The most powerful version in the end - the 88mm Flak 41 - had a cadence of up to 25 rounds per minute and was considered a powerful German anti-aircraft gun.
The high losses in the Allied bomber formations was a high material usage over: the Quartermaster General of the Air Force calculated for the shooting down of a four-engined bomber consumption of 16,000 shot with the "88mm Flak 36" and 8500 shot with the "8.8 -cm-Flak 41 ". The 10.5 cm Flak 38 required an average of 6,000 rounds and the heavy 12.8 cm Flak 40 3,000 rounds.
Until shortly before the end of the war, the projectiles of the larger anti-aircraft cannons above the 4 cm caliber only had time fuses . A clockwork (type ZtZ S / 30) developed by the Uhrwerke Gebr. Thiel (→ Gerätebau GmbH ) was built into the head of the grenade, which ignited the grenade after an adjustable running time of 1.5 to 29.5 seconds. The delay time was calculated by the so-called "command device". This mechanical analog computer determined the lead and thus the duration of the projectile from the values determined for the course and altitude of the aircraft . Before firing, the delay time had to be set in the "fuse setting machine" on each grenade. Since there was no impact fuse, it often happened that the anti-aircraft shell penetrated a part of the aircraft and only exploded far behind. With the introduction of additional impact fuses (double fuses), which did not take place until 1945 despite the requirement, the rate of fire could be tripled.
After the Dambusters -Angriffen 1943 a new system was designed to be low approaching aircraft ( " low-flying combat"). At first, experiments were carried out with a 5 cm cannon; However, as this turned out to be imprecise, it was later replaced by a 5.5 cm version. The system used a central control system that contained both search and fire control radar , calculated the target point for the guns and sent corresponding control commands to the hydraulic drives of the guns. The crew only had to reload the guns and choose the targets. The system was very modern for the state of the art at the time and was in the final phase of development at the end of the war.
From 1943 on, high school students born in 1926 to 1928 were drafted in classes to support the flak soldiers. These flak helpers , officially called Luftwaffe helpers , were used on all devices and weapons used at the time to protect the Reich territory.
- 2 cm Flak 30
- 2 cm Flak 38
- 20 mm Oerlikon cannon
- 2 cm anti-aircraft quadruplet 38
- 2 cm mountain flak 38
- 2 cm aircraft guns mounted on a base
- 3.7 cm Flak 37
- 3.7 cm Flak 43
- 3.7 cm anti-aircraft gun twin 43
- 40 mm Bofors gun (Bofors / Sweden and captured weapons)
- 5 cm Flak 41
Radio measuring devices ( radar )
Flak evaluation device Malsi
The flak evaluation device named after Major dR Georg Malsi could be used to determine the settings of the guns in the event of failure of the command device. In special situations - for example during deep attacks - the device was able to determine values for barrages . All values were transmitted to the guns using larynx microphones.
The device was in the so-called "revaluation" within the command post. There were also in this protected space
- the message center as a connection point to the flak group,
- a glass board with the so-called Jägergradnetz to track incoming enemy planes
- and the measuring table to represent the goals you have set yourself.
In addition to the Malsium evaluation, the so-called "Hutzenlaube conversion" was also used to control anti-aircraft guns and searchlights. Here, too, the data was transmitted with three values over the telephone line and was recorded and processed with the larynx microphone. The hood revaluation automatically controlled the anti-aircraft gun and headlights via a 108-core cable if required.
At the beginning of the war, Britain had just begun the hesitant renewal of its air defense systems, including a 90mm cannon to supplement the old 3-inch guns from the First World War. Both were equipped with optical target systems. As in the German Empire, experiments were initially carried out with 20 mm designs; however, it was also concluded that these systems were of limited use against modern aircraft.
The British solution consisted of a 40mm cannon , also based on the Bofors design. With it, aircraft of any size could be shot down, provided they were within 4000 meters. Still, the gun was light enough to be mobile and easy to pivot. This gun became so important to the British that they even made a film about it (The Gun) to better motivate workers on the assembly lines.
In practice, the problem arose that an accurate range estimate and tracking of the new high-speed targets was almost impossible - at short range the required lead was so small that it could be estimated manually; at very great distances the apparent speed of the target is so slow that a simple slide rule is sufficient. In between, you got serious problems.
The solution was automation in the form of a mechanical computer, the Kerrison Director . The gun operator held it on target and the director calculated the correct target point and indicated it using a pointer mounted on the gun. The crew then simply followed the pointer and reloaded the gun. The Kerrison Director paved the way for the later use of radar ; initially for distance measurement, later also for tracking.
The Red Army used anti-aircraft guns in calibers of 25, 37, 76 and 85 mm during the Second World War. Main models were:
- 25mm automatic anti-aircraft gun M1940 (72-K) ,
- 37mm automatic anti-aircraft gun M1939 (61-K) ,
- 76 mm anti-aircraft gun M1931 (3-K) ,
- 76 mm anti-aircraft gun M1938 ,
- 85 mm anti-aircraft gun M1939 (52-K) .
In the European theater of war, anti-aircraft guns were also used by the US Army to protect ground troops during World War II . A .50 (12.7 mm) quadruple machine gun was often mounted on an M16 half-track vehicle ; which became the M16 AA (in English , flak is called AA , which stood for a nti a ircraft). Their even lower impact than that of the German 20 mm guns made up for them in part with their high availability. The larger 90 mm cannons, like the German eight-eight, proved to be excellent anti-tank guns and were used in this role long after the war. Shortly before the end of the war, a new 120 mm gun with an impressive summit height of 14,600 meters was introduced, which was also used well into the 1950s.
The American air defense was of great importance in the naval war against Japan , where, for example, the 40 mm Bofors guns - often with automated lead determination - were successfully used against the Japanese naval aviators .
During World War II, the Americans were the only power to succeed in mass-producing functional proximity fuses for anti-aircraft shells and installing them in projectiles down to a diameter of three inches. Until shortly before the end of the war, for fear of the enemy discovering the secret, these were only used over the sea or over their own territory. The detonators delivered to Great Britain significantly increased the rate of release of V1 flying bombs.
Post-war until today
Analyzes had shown that, despite modern air defense systems on both sides, around 90 percent of the enemy bombers reached their target. During the war it was an acceptable problem, but with the proliferation of the atomic bomb it was already unacceptable for a single bomber to reach its destination.
For a short time after the war, the anti-aircraft guns were improved. The United States Armed Forces, in particular , set up a large anti-aircraft network around the larger cities, consisting of 90 and 120 mm radar guns. Since anti-aircraft guns were not very successful even against propeller-driven bombers, the air defense system soon relied almost exclusively on interceptors .
In post-war Germany until the mid-1990s, 20-mm Rheinmetall automatic cannons in single and double-barreled versions were used for active airfield and property protection .
That changed with the introduction of the anti-aircraft missile . Although the Germans had already researched in this direction during the war, no ready-to-use specimens were produced - with the exception of the "Jagdfaust" rockets, which were mounted on machines of the Me 163 "Komet" type , and the unguided R4M used by the Me 262 - Missiles. Even if the existing ground-based anti-aircraft missiles had been of practical use, they could easily have been deflected by existing British countermeasures. However, after a few more years of development, these systems matured into important weapons. The US soon replaced its anti-aircraft guns with the Nike Ajax missile.
A further development direction of the artillery are short-range defense systems , which should automatically intercept missiles up to rockets and artillery shells. The American Phalanx CIWS or the German short-range protection system MANTIS can be named as representatives.
At the end of 2012, Rheinmetall presented an air defense system that uses two laser beams instead of conventional projectiles or missiles.
Advantages and disadvantages of guns and missiles
Since the introduction of reliable short-range missiles, a gradual change from guns to missiles can also be observed for short-range weapons. Originally, missiles could only replace long-range anti-aircraft guns, but from the 1960s onwards they were small enough to be sufficiently accurate even at medium range. Today, portable missiles of the Strela-2 , Strela-3 and FIM-92 Stinger types can replace even the smallest anti-aircraft guns.
Until 2010 , the Bundeswehr owned the Gepard, one of the most modern flak tanks , which was equipped with two 35 mm automatic cannons with a range of up to 5000 meters and had a highly developed active fire control system. However, these can be combated by Wild Weasel aircraft with Suppression of Enemy Air Defenses . The air defense of all troops against combat helicopters is now also carried out by on-board machine cannons of armored personnel carriers.
Because of certain tactical features, anti-aircraft guns are still used today. For reasons of cost, they are particularly common in less developed countries; an example of this is the ZSU-23-4 anti-aircraft tank developed in the Soviet Union .
The anti-aircraft guns still have some advantages over anti-aircraft missiles. This includes the ability to defend oneself against ground troops, the relative insensitivity to disruptive measures, the cheaper and easier ammunition to be accommodated in the vehicle, and a faster reaction than missiles (there is no need to interfere).
A special feature, especially of multiple guns, is the system-related spread of the bullet trajectories at high rate of fire, which makes special accuracy when aiming the guns unnecessary. This allows guns to fire barrages to make selected areas of the air impassable; this method is used today for field camp protection.
Most anti-aircraft guns fire explosive ammunition against targets. The probability of a direct hit on the target is low. An improvement in the hit rate is achieved by deliberately increasing the spread of the guns. The detonator built into the projectiles generally triggers the explosion in the following three cases:
- In the event of a direct hit by a proximity or impact fuse
- If detonated near the target by proximity detonators,
- After an adjustable flight time has elapsed, a timer is used to detonate the projectiles as close as possible to the target.
Grenades with an impact or proximity fuse usually have an additional detonator fuse so that your own troops are not endangered by falling grenades.
As a rule, the necessary detonator runtime is automatically set by the fire control system immediately before firing. Towards the end of the Second World War, the British initially equipped their larger-caliber anti-aircraft shells with a kind of miniaturized radar sensor that automatically detonated when the target was approached. This technique was used to fight the German V1 , for example .
Other types of ammunition are often available to combat ground targets, such as armor-piercing projectiles. In the case of very small-caliber anti-aircraft weapons, full projectiles are sometimes used against air targets, for example in the American Phalanx CIWS . On the one hand, the high rate of fire means that the hit probability is higher, and on the other hand, the splinters would have little effect.
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- HWL Moedebeck, Die Luftschiffahrt . 1906, in it Chapter 8, p. 126 ff. "Combating the airships with the artillery" can be viewed online
- Werner Müller:
- The light and medium flak 1906–1945. Used in the armed forces on all fronts. 2 cm, 2 cm SKC / 30, 3.7 cm SKC / 30, 4 cm, 5 cm, 5.5 cm . MTM-Verlag, Bad Soden-Salmünster 1999, ISBN 3-934507-00-X .
- 8.8 Flak on all fronts (= Das Waffen-Arsenal , special volume S 52). Podzun-Pallas, Wölfersheim-Berstadt 1998, ISBN 3-7909-0639-5 .
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- Photo: RIA Novosti archive, image # 5634 / David Trahtenberg / CC-BY-SA 3.0
- balloon cannon from Krupp, with pivot mount, description of the exhibit with inventory number 544 W History at the Deutsches Museum (consulted on 25 November 2013).
- and history of the Le Daguerre balloon (accessed November 25, 2013)
- Moedebeck: Die Luftschiffahrt , page 129 (available online) .
- Hermann Cron: History of the German Army in World Wars 1914-1918 . Berlin 1937, p. 215 (Neudruck, Osnabrück 1990).
- Ralf Schabel: The illusion of miracle weapons. The role of jet planes and anti-aircraft missiles in the armaments policy of the Third Reich . (= Contributions to military history , vol. 35). Oldenbourg-Verlag, Munich 1994, ISBN 3-486-55965-6 , p. 260.
- Oberrealschulen and Realgymnasien were uniformly renamed “Oberschule” during the Nazi era from 1937 to 1945. They led to the Abitur.
- Louis Goddard: Double-barreled 50 kW laser weapon shoots down drones and mortar rounds. In: The Verge . December 23, 2012, accessed July 23, 2017 .