Flak

Flak or FlaK is the abbreviation for the German weapon Flugabwehrkanone or Fliegerabwehrkanone (English: anti-aircraft gun or aircraft defence cannon). Flak or Fla is also used as a name for the anti-aircraft force in general. The term was introduced to the English language in World War II, although in this case written "flak" and mainly referring to the anti-aircraft fire coming from the anti-aircraft guns. The units of the branch Flakartillerie (Flugabwehrartillerie or Flak-Artillerie) in the German Wehrmacht were subordinate to the Luftwaffe. Their weapon color was bright red. In addition, there were army anti-aircraft artillery in the Heer and naval anti-aircraft units in the Kriegsmarine.

Luftwaffe Flak Battle Badge (Flak-Kampfabzeichen der Luftwaffe)

History

FlaK-Panzer "Grille 10": 8.8 cm FlaK 41 on special chassis (modified Panzer IVc chassis)

German 88 mm flak battery of the Luftwaffe in action against Allied terror bombers

Army Anti-Aircraft Flak Battle Badge (Heeres-Flakabzeichen)

Anti-aircraft position during a combat break in France on the invasion front, 21 June 1944

Luftwaffenhelfer by Herbert Smagon

Memorial to the fallen of the Anti-Aircraft Artillery by Felix Kupsch in Berlin-Steglitz

In the German Empire, the development of anti-aircraft guns was already underway before the start of the First World War. In 1909, the Krupp company presented a number of variants of its 6.5 cm, 7.5 cm and even 10.5 cm guns for anti-aircraft defense. However, tests soon showed that normal field guns were unsuitable due to their low projectile speed and the resulting excessively curved trajectory. In 1913 and 1914, the Prussian Army carried out shooting exercises on the Baltic Sea with Krupp and Ehrhardt guns, which could be swiveled 360° on pivot mounts. Military tacticians initially saw the main target as being less the enemy aircraft than tethered balloons or military airships, which is why the term Bak for balloon anti-aircraft gun initially prevailed. It was changed to anti-aircraft gun in May 1916.

Other countries did not believe that aircraft could play an important role in military conflicts at that time, but soon after the war began, French pilots proved this wrong. They used small reconnaissance aircraft to direct artillery strikes with astonishing accuracy. All armies therefore soon began using their smaller guns of up to 75 mm against aircraft, which were usually simply jacked up so that the barrel pointed towards the sky. The British Army developed a new 3-inch caliber weapon.

World War I

Since the first Zeppelin made its first flight over Lake Constance on 2 July 1900, the German General Staff generally considered the airship and not the airplane to be an important weapon that should be used as a bomb carrier and for aerial reconnaissance. This assessment remained unchanged until the outbreak of the First World War.

Contrary to the expectations of the German General Staff, however, the tasks assigned to the military airship by the enemy were mainly carried out by aircraft. The rigidity of the fronts in the West also favored the fundamental further development of the aircraft's function from an artillery observer to a bomb carrier. This meant that targets in enemy territory that were far behind the front and therefore beyond the reach of artillery could also be attacked.

Two things quickly became clear to the Imperial German Army:

• Firstly, with the few anti-balloon guns available (8 Bak or 18 with older test vehicles) and the expected 7.7 cm guns from forced production, the existing danger from the enemy's aircraft could not be contained in bulk. In order to alleviate this quantitative shortage of anti-aircraft guns, makeshift anti-aircraft guns were used from the end of 1914, which had to continue to be used throughout the war.

• Secondly, the previous anti-aircraft guns and the ammunition used in the Feldkanone 96 were, in terms of their performance data, not very suitable for combating aircraft: in principle, aircraft and Zeppelins both used the possibilities of movement in the three dimensions of space. However, the airplane was significantly faster than the Zeppelin. For these reasons, the projectile flight time had to be minimized again compared to the existing anti-balloon guns (Bak) in order to reach the target quickly (a low projectile flight time is in principle only achieved through a particularly high initial speed of the projectile).

At the beginning of 1915, the Supreme Army Command (Oberste Heeresleitung; OHL) ordered round tables with artillery officers and representatives of the companies Krupp (Professor Rausenberger) and Rheinmetall (Director Völler) in order to incorporate the troops' previous front-line experience into the companies' development work. In January 1915, there was a meeting at the Imperial Grand Headquarters (Königliche Großes Hauptquartier) in Charleville with officers from the Western Front, and in February 1915, one with officers from the Eastern Front in Berlin. In addition to troop officers, representatives of the Artillery Examination Commission (APK), the War Ministry (KM), the Army Field Equipment Inspection (Fz) and the OHL were also present. The companies Krupp and Rheinmetall were commissioned to develop special anti-aircraft guns with larger calibers (8.0, 8.8 and 10.5 cm), better ballistic performance and semi-automatic bolts for rapid fire.

In December 1916, Krupp and Rheinmetall each delivered two 8.8 cm and 10.5 cm anti-aircraft guns (Flugabwehrgeschütze) to the army. The two armaments companies had developed these new gun types separately. However, the "competing" 8.8 cm anti-aircraft guns from both companies had identical barrel lengths, the same V0 and fired the same ammunition. The ballistic performance of the 10.5 Flak from Rheinmetall (V0 = 580 m/sec) was worse than that of the Krupp gun (V0 = 720 m/sec). The main reason for this difference was that no standard ammunition was used for the 10.5 cm anti-aircraft guns, but rather the company's own developments. The Rheinmetall projectile weighed 18.3 kg, which was 0.9 kg heavier than the Krupp one.

From the beginning of 1916, there was a general attempt to have gun production carried out by more than just traditional manufacturers in order to increase output. The newly developed German anti-aircraft guns were in principle exempt from this. This was due on the one hand to their complexity, and on the other hand to the fact that new experiences from the front were still being incorporated into their design. However, as the Krupp and Rheinmetall factories were overloaded with production orders and aircraft, despite their growing importance, still posed the least of the threats, the development process and production were delayed. A new cartridge was also developed for anti-aircraft artillery: the most important innovation was the development of mechanical time fuses by the Thiel (Krupp) and Junghans companies. The Thiel timer had a mechanical clockwork, while the Junghans fuse worked with the rotation of the projectile. Due to the fact that the production facilities for these fuses had yet to be built, they could only be introduced from 1918 onwards for the 7.62 cm Flak (M.K.Z. 17 by Junghans) and for the 8.8 cm Flak (D.Z. 16 by Thiel).

In general, however, these ad hoc solutions proved largely ineffective. Without experience in engaging air targets and without the ability to accurately determine the location of their salvos, the artillerymen were overwhelmed, as they could only estimate the target's altitude. Most of the defensive fire was well below the target. The exception to this rule was the guns supported by reconnaissance balloons. In this case, the target's altitude could be determined very precisely by the length of the tether cable holding the balloon. The Krupp guns were later equipped with an optical aiming system that significantly improved their hit rate, but other armies did not initially use these techniques.

When aircraft were also used for tactical attacks against ground targets, the large guns proved too cumbersome to aim at the fast-moving aircraft. At first, the troops used their regular machine guns for anti-aircraft defense, but the development of smaller cannons began quite soon; The British, for example, introduced an anti-aircraft weapon based on a 1-pounder (37 mm) gun with ammunition fed via a belt. The German army, in turn, used a rapid-firing 3.7 cm machine gun. These short-range weapons proved to be far more accurate. As the war drew to a close, it was clear that the ability to shoot down aircraft would require a more serious approach. The German military historian George Soldan cited statistics that showed that for every 12,000 anti-aircraft shots, one hit was scored.

Between wars and World War II

World War I had shown that airspace had become an important part of the battlefield. As aircraft capabilities continued to improve, especially with more powerful engines, it became clear that their future role in combat would be much more extensive than before. In the early 1930s, most countries developed special anti-aircraft guns. Often, several machine guns were combined into one anti-aircraft gun to increase firepower. While the British and Americans traditionally had the protection of their fleet in mind, other countries developed the guns to protect ground troops.

Anti-aircraft artillery was one of the branches of the military that the German Reich was not allowed to establish under the Treaty of Versailles. When the German Reich began rearmament (1933–1945), the department of the Reich Defense Ministry, previously disguised as a motorized transport battalion (Fahrabteilung), was established in the Luftwaffe in 1935.

Against the backdrop of the Sudetenland Crisis, at the end of May 1938, Germany first began to consider setting up an anti-aircraft zone (West Air Defense Zone) in the hinterland of the West Wall, which was under construction. As early as the beginning of June 1938, the first orders for the German Luftwaffe to build bunkered, fortress-like anti-aircraft batteries were issued. The attacking air forces were to be hindered when flying into the Reich and forced to fly at altitudes of over 6,000 meters. These anti-aircraft batteries were also to pose a serious threat on the return flight. At the beginning of the Second World War, anti-aircraft tower systems were developed in Germany, which consisted of a control tower and a combat tower, as an elevated position was necessary in densely built-up urban areas. These included bunkers, including for the civilian population.

A number of new anti-aircraft guns were also developed in the German Reich, including a 2 cm rapid-fire low-altitude gun and a 3.7 cm gun for low and medium altitudes. By the mid-1930s, the 2 cm gun was already considered too weak against the increasingly faster aircraft, but rather than develop a new gun, Krupp mounted four of these 2 cm guns on a common carriage, thereby increasing firepower considerably. By the end of the war, the 2 cm gun was no longer sufficient, but with the 3.7 cm variant only being available in limited quantities and a new system based on the 3 cm MK 103 never gaining widespread use, it could not be dispensed with.

The need for high-altitude anti-aircraft defense was originally to be met by an improved 7.5 cm design from Krupp, but the requirements were later changed to require higher performance. Krupp's engineers therefore worked with Bofors in Sweden (a traditional Swedish arms manufacturer) 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 divisible barrel (the rear part wears more due to the ignition taking place there). The cannon, colloquially known 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 (Condor Legion; F/88), the cannon proved to be one of the best anti-aircraft guns in the world and also particularly effective against tanks. Unlike many other types, the eight-eight can also be aimed below the horizontal, i.e. can also fire "downhill".

This weapon proved to be the only effective weapon against heavy tanks, especially in ground operations, until the appearance of improved anti-tank guns, and in this role it was known and feared, especially by the Allies. Because of its high penetrating power, a modified version of the "Acht-Acht" was installed as a tank gun in the Tiger Panzer. Its firing and penetrating power was improved mainly by further developing the ammunition and extending the barrel. The ultimately most powerful version – the 8.8 cm Flak 41 – had a rate of fire of up to 25 rounds per minute and was considered the most powerful German anti-aircraft gun.

The high losses suffered by the Allied bomber units, such as those in the Central German anti-aircraft belt, were offset by a high use of materials: the Quartermaster General of the Luftwaffe calculated that shooting down a four-engine bomber would require 16,000 rounds with the "8.8 cm Flak 36" and 8,500 rounds 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 required 3,000 rounds.

Until shortly before the end of the war, the projectiles of the larger anti-aircraft guns with a caliber of over 4 cm only had time fuses. A clockwork (type ZtZ S/30) developed by the Gebr. Thiel watch factory (→ 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 analogue computer determined the lead and thus the running time of the projectile from the determined values ​​of the aircraft's course and altitude. Before firing, the delay time had to be set in the "fuze setting machine" on each grenade. Since there was no impact fuse, it often happened that the anti-aircraft grenade penetrated part of an aircraft and only exploded far behind it. The introduction of additional impact fuses (double fuses), which did not take place until 1945 despite a request, meant that the firing rate could be roughly tripled.

After the Dambusters attacks in May 1943, a new system was developed to combat low-flying aircraft (“strafing”). Initially, tests were carried out with a 5 cm cannon; however, as this proved to be inaccurate, it was later replaced by a 5.5 cm variant. The system used a central control system that contained both search and fire control radar, calculated the aiming point for the guns and sent the corresponding control commands to the hydraulic drives of the guns. The crew only had to reload the guns and select 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, high school students born between 1926 and 1928 were drafted in classes to support the anti-aircraft soldiers. These anti-aircraft helpers (Flakhelfer), officially known as Luftwaffenhelfer, were deployed on all equipment and weapons used at the time to protect the Reich (Reichsverteidigung).

Schools

A well-known anti-aircraft artillery school (Flakschule) was located in Döberitz. The commander was Alfred Haubold in 1934/35. The largest anti-aircraft artillery school, the FAS I, was located in Rerik on the Wustrow peninsula. The anti-aircraft artillery school II was also located on the Baltic Sea in Stolpmünde. The Wehrmacht had seven Flakartillerieschulen and at least another 17 field Flak schools (Feld-Flakartillerie-Schulen).

Flaks

Light Flak

• 10.5 cm Flak 38
• 2 cm Flak 30
• 2 cm Flak 38
• 20 mm Oerlikon cannon
• 2 cm Flak Vierling 38 (quad anti-aircraft gun)
• 2 cm mountain Flak 38
• 2 cm aircraft cannons mounted on base

Medium Flak

• 3.7 cm Flak 37
• 3.7 cm Flak 43
• 3.7 cm Flak Zwilling 43 (twin anti-aircraft gun)
• 40 mm Bofors gun (Bofors/Sweden and captured weapons)
• 5 cm Flak 41

Heavy Flak

• 8.8 cm Flak 18/36/37
  • The 8.8 cm Flak 18/36/37, also called Acht-Acht or Acht-Achter, was a German anti-aircraft gun built and used primarily during World War II, but also frequently used against ground targets.
• 8.8 cm Flak 41
  • The 8.8 cm Flak 41 was a completely new development that was created to keep up with the increasing altitudes of enemy aircraft, such as in the Central German anti-aircraft belt. Although it had the same caliber as its predecessors, the 8.8 cm Flak 18/36/37, it used different ammunition than the earlier models.
• 10.5 cm Flak 38
• 12.8 cm Flak 40
• 12.8 cm Flak-Zwilling 40 (twin anti-aircraft gun)
  • The 12.8 cm Flak-Zwilling 40 was a further development of the 12.8 cm Flak 40. The second barrel doubled the rate of fire to up to 28 rounds per minute. The doubled weight was not important, as the anti-aircraft gun was only used in a fixed position in a base mount, mostly on anti-aircraft towers or, for example, on the Central German anti-aircraft belt. Only a very few of the very expensive anti-aircraft guns were manufactured by Hanomag in Hanover and Oberschlesische Gerätebau GmbH in Laurahütte. The highest stock was reached in January 1945 with 33 units. The 12.8 cm Flak-Zwilling 40 could fire 26 kilogram explosive shells to a height of 14,800 meters. The service life of a barrel was approximately 1,000 to 2,000 rounds.

Radars

Funkmeßgeräte:

• FuMG 39 "Würzburg"
  • The code name "Würzburg" was used for the mobile radio measuring device in the decimeter wave range developed by Telefunken (designation: radio transceiver FuSE 62 or radio measuring device FuMG 62; initially also FMG 39; anti-aircraft measuring device), which the German Air Force used on a large scale in World War II to guide Nachtjäger and anti-aircraft guns.
• FuMG 65 "Würzburg-Riese"
  • The stationary "giants" (designation: radio transceiver FuSE 65 or radio measuring device FuMG 65) introduced in mid-1941 were used to guide the Luftwaffe's night fighters and were installed on the control towers of the large anti-aircraft towers for fire control. The mobile Würzburg giants FuSE 65 E were mounted on railway carriages, while the stationary version for the Kriegsmarine was the radio measuring and locating device FuMO 214, which was used to control the fire of its coastal artillery (e.g. at the Fjell fortress).
• FuMG 40 "Mainz"
• FuMG 40 L "Kurmark"
• FuMG 41 "Mannheim"

See also

• Flakhelfer

External links

• General der Flak-Ausbildung
• General der Flakartillerie