8.8 cm Flak 18/36/37/41

The 88 mm gun (commonly called the eighty-eight) was a German anti-aircraft and anti-tank artillery gun from World War II. It was widely used by Germany throughout the war, and was one of the most recognized German weapons of that conflict. Development of the original models led to a wide variety of guns.

The name applies to a series of guns, the first one officially called the 8.8 cm Flak 18, the improved 8.8 cm Flak 36, and later the 8.8 cm Flak 37. Flak is a contraction of German Flugzeugabwehrkanone meaning "aircraft-defense cannon", the original purpose of the eighty-eight. In English, "flak" became a generic term for ground anti-aircraft fire. In informal German use, the guns were universally known as the Acht-acht ("eight-eight").

The versatile carriage allowed the eighty-eight to be fired in a limited anti-tank mode when still on its wheels; it could be completely emplaced in only two-and-a-half minutes. Its successful use as an improvised anti-tank gun led to the development of a tank gun based upon it. These related guns served as the main armament of tanks such as the Tiger I: the 8.8 cm KwK 36, with the "KwK" abbreviation standing for KampfwagenKanone (literally "battle vehicle cannon", or "tank cannon").

In addition to these Krupp designs, Rheinmetall later created a more powerful anti-aircraft gun, the 8.8 cm Flak 41, which was produced in relatively small numbers. Krupp responded with another prototype of the long-barreled 88 mm gun, which was further developed into the anti-tank and tank destroyer 8.8 cm Pak 43 gun used for the Elefant and Jagdpanther, and turret-mounted 8.8 cm KwK 43 heavy tank gun of the Tiger II.

Background
Initially, anti-aircraft artillery guns of World War I were adaptations of existing medium-caliber weapons, mounted to allow fire at higher angles. By 1915, the German command realized that these were useless for anything beyond deterrence, even against the vulnerable balloons and slow-moving aircraft of the period. With the increase of aircraft performance, many armies developed dedicated AA guns with a high muzzle velocity – allowing the projectiles to reach greater altitudes – and a high rate of fire. The first such German gun was introduced in 1917, and it used the 88 mm caliber, common in the Kaiserliche Marine German navy.

After losing the war, Germany had been forbidden from procuring new weapons of most types. Nevertheless, the Krupp company started the development of a new gun in partnership with Bofors of Sweden. The original design was a 75 mm model. During the prototype phase, the army asked for a gun with considerably greater capability. The designers started again, using 88 mm caliber.

Flak 18, 36 and 37
Prototype 88s were first produced in 1928. These early models, the Flak 18, used a single-piece barrel with a length of 56 calibers, led to the commonly-seen designation L/56.

The Flak 18 was mounted on a cruciform gun carriage. A simple to operate "semi-automatic" loading system ejected fired shells, allowing it to be reloaded by simply inserting a new shell into a tray. The gun would then fire, recoil, and, during the return stroke, the empty case would be thrown backward by levers, a cam would then engage and recock the gun. This resulted in firing rates of 15 to 20 rounds a minute, which was better than similar weapons of the era. High explosive ammunition was used against aircraft and personnel, and armour-piercing and high-explosive anti-tank against tanks and other armored vehicles.

Widespread production started with the Nazi rise to power in 1933, the Flak 18 was available in small numbers when Germany intervened in the Spanish Civil War. It quickly proved to be the best anti-aircraft weapon then available. The flak detachment with 88s proved accurate and versatile in combat against mainly land targets, the high muzzle velocity and large caliber made it an excellent long-range anti-vehicle and anti-bunker weapon. This experience also demonstrated a number of minor problems and potential improvement opportunities.

Many of these were incorporated into the Flak 36, which had a two-piece barrel for easier replacement of worn liners. The new, heavier, carriage allowed it to fire in an emergency when still on its wheels and without its outriggers, but with a very limited traverse and elevation. For normal emplacement, one single-axle bogie was detached from the front outrigger and one from the rear, side outriggers were then hinged from the vertical position to the ground; the total time to setup was estimated at two-and-a-half minutes. Both modes of operation made the gun much more suitable for fast-moving operations, the basic concept of the blitzkrieg. Flak 36s were often fitted with an armoured shield that provided limited protection for the gunners. The weight of the gun meant that only large vehicles could move it, the SdKfz 7 half-track became a common prime mover. Targeting indicators were attached from the central controller to each of the four guns of a battery, allowing for coordinated fire. Indeed, with the automatic loading system, the gun layers' job was to keep the gun barrel trained on the target area based on the signals from the controller. The loaders would keep the weapon fed with live ammunition which would fire immediately upon insertion—all while the gun layer aimed the weapon according to the data.

The later Flak 37 included updated instrumentation to allow the gun layers to follow directions from the single director more easily. The parts of the various versions of the guns were interchangeable, and it was not uncommon for various parts to be "mixed and matched" on a particular example. Some sources mistakenly cite that the Flak 37 was not equipped for anti-armor purposes. The fact is all 8.8 cm guns were capable of the dual role.

8.8 cm Flak 41
Due to the problems of defending against attack by high-flying aircraft the Luftwaffe asked for newer weapons with an even better performance as early as 1939. Rheinmetall responded with a new 88 mm design with a longer cartridge and a longer barrel. A prototype was ready in early 1941 leading to the designation 8.8 cm Flak 41. The new gun fired a 9.4 kg shell at a muzzle velocity of 1,000 m/s (3,280 ft/s), giving it an effective ceiling of 11300 m and a maximum of 15000 m, which General Otto Wilhelm von Renz said to be "almost equal to the 128-mm." It featured a lower silhouette on its turntable mounting than did the 8.8-cm Flak 18/36/37 on its pedestal mounting. The barrel was at first a three-section one with a length of 74 calibers, and then redesigned to dual-section with a length of 72 calibers. Improvements in reloading raised the firing rate, with 20 to 25 rounds a minute being quoted.

Because of problems in service, the guns were almost exclusively used in Germany where they could be properly maintained and serviced. The Flak 41 had the disadvantage of complexity, and was prone to problems with ammunition, empty cases often jamming on extraction. Because of the high cost and complexity of this weapon, the Germans manufactured relatively few of them, 556 in all. The first deliveries were made in March 1943 and, as of August 1944, only 157 were fielded; with 318 in January 1945. A final adaptation, known as the Flak 37/41, mounted the Flak 41 gun on the Flak 37 carriage, of which only 13 were produced.

Production numbers
Thousands of 88 mm guns were produced throughout the war in various models and mounts.

Compared to other artillery types, German industry built for example, 570 heavy (caliber 88–128 mm) flak guns, 1,020 field artillery pieces (caliber 75–210 mm), and 1,300 tank guns, anti-tank guns, plus self-propelled guns in December 1943.

Combat history
The eighty-eight was used in two roles: as a mobile heavy anti-aircraft gun, and in a more static role for home defence.

Anti-aircraft defense of the Reich
Since 1935, the anti-aircraft defense of Nazi Germany was controlled by the Luftwaffe. By the beginning of World War II (which is usually regarded as 1 September 1939), the Luftwaffe's anti-aircraft artillery employed 6,700 light (2 cm and 3,7 cm) and 2,628 heavy flak guns. Of the latter, a small number were 10.5 cm Flak 38s or 39s, the majority were 8.8 cm Flak 18s, 36s or 37s. This was twice as many heavy AA guns as the Air Defence of Great Britain (ADGB) had at the time, with France and the United States having even less.

Throughout the entire war, the majority of 88 mm guns were used in their original anti-aircraft role.

The pecuniary costs associated with anti-aircraft cannon were substantial, especially when compared to fighter aircraft. For example, in January 1943 – at a time Germany was desperately fighting to regain the strategic initiative in the East and was also facing a heavy bombing campaign in the West – expenditures on anti-aircraft defenses were 39 million reichsmarks, whereas all the remaining weapons and munitions production amounted to 93 million (including 20 million of the navy budget and only nine million of the aircraft-related budget).

By August 1944, there were 10,704 Flak 18, 36 and 37 guns in service, now complemented also by the formidable 12.8 cm Flak 40, owing to the increase in US and British bombing raids during 1943 and 1944. There were complaints that, due to the apparent ineffectiveness of anti-aircraft defenses as a whole, the guns should be transferred from air defense units to anti-tank duties, but this politically unpopular move was never made.

Support of German ground troops
The 88 performed well in its original role of an anti-aircraft gun, but it proved to be a superb anti-tank gun as well. Its success was due to its versatility: the standard anti-aircraft platform allowed gunners to depress the muzzle below the horizontal, unlike most of its contemporaries. During the initial stages of the war, as it was becoming increasingly clear that existing anti-tank weapons were unable to pierce the armor of heavier enemy tanks, gunners were more likely to put the weapon to use against enemy tanks, a situation that was aided by the prevalence of the 88 among German forces.

Similarly to the anti-aircraft role, as an anti-tank weapon the 88 was tactically arranged into batteries, usually four guns to each. The higher-level tactical unit was, most commonly, a mixed anti-aircraft battalion (Flak-Abteilung, gemischte). It totaled 12 such guns on average, supplanted by light cannons.

The German Condor Legion made extensive use of the 88 in the Spanish Civil War, where its usefulness as an anti-tank weapon and a general artillery piece exceeded its role as an anti-aircraft gun.

For the 1940 Battle of France, the army was supported by eighty-eights deployed in twenty-four mixed flak battalions. The eighty-eight was used against heavily armored tanks such as the Char B1 bis and Matilda II, whose frontal armour could not be penetrated by the light 3.7 cm anti-tank guns then available. The 88 was powerful enough to penetrate over 84 mm of armor at a range of 2 km, making it an unparalleled anti-tank weapon during the early days of the war, and still formidable against all but the heaviest tanks at the end. Erwin Rommel's timely use of the gun to blunt the British counterattack at Arras ended any hope of a breakout from the blitzkrieg encirclement of May 1940. In the entire Battle of France, the weapon destroyed 152 tanks and 151 bunkers.

During the North African campaign, Rommel made the most effective use of the weapon, as he lured tanks of the British 8th Army into traps by baiting them with apparently retreating German panzers. When the enemy tanks pursued, concealed 88s picked them off at ranges far beyond those of their 2-pdr and 6-pdr guns. A mere two flak battalions destroyed 264 tanks throughout 1941.

For the invasion of the Soviet Union, Germany deployed the 88 in 51 mixed AA battalions. They were mostly Luftwaffe-subordinated units attached to the Heer at corps or army level, with approximately one battalion per corps. The weapon saw continuous use on the eastern front. The appearance of the outstanding T-34 and KV tanks shocked the German panzer crews and anti-tank teams, who could only penetrate the Soviet tanks' armor at extremely close range when using the standard 37 mm and 50 mm guns.

The 88 was arguably most effective in the flat and open terrain of Libya, Egypt and the eastern front. The less open terrain in Italy and Northern France was less suitable for it. The success of the 88 caused the Allies to take steps to defend against it in new tank designs.

On July 18th and 19th 1944 a Luftwaffe 8.8cm anti-aircraft battery was re-purposed by then Major Hans von Luck to attack British tanks near Cagny taking part in Operation Goodwood. 20 tanks were killed by these guns within the first few seconds and at least 40 tanks were knocked out by 88's during the engagement.

By February 1945, there were 327 heavy anti-aircraft batteries delegated against the Soviet land armies, which was 21% of those dedicated solely to the anti-aircraft defense of the country.

Coastal defence
On 14 September 1942, Flak-Abt. I./43 (Major Wegener) employed these guns against a commando landing raid called Operation Agreement by the British Royal Navy near Tobruk, damaging the destroyer HMS Sikh so severely that she sank while being towed by HMS Zulu.

China
In 1937, the Chinese Nationalist Government imported 20 Flak 18 guns and used them to defend the Castles along the Yangtze River. They were captured by the Japanese Imperial Army during the Sino-Japanese War.

Spain
Four batteries ( 16 guns) of 88mm guns (Flak. 18) initially reached Spain as AA with the Condor Legion in 1936, but it was soon used as anti-tank, anti-bunker and even as anti-battery. More guns were sent later and some more 88-mm guns were supplied to Spanish army units. At the end of the war the Spanish Army AA was using all of them, 52 guns Flak 18 88/56mm.

The Flak 18 batteries initially were deployed to protect the airfields and logistics bases used by German Condor legion. The nature of war in Spain, with its wildly fluctuating front lines and the presence of Russian tanks, forced the Germans to employ the Flak 18 guns in a direct fire mode against ground targets. Besides this, the initial scarcity of Nationalist Spanish artillery and the general low proficiency of its crews soon forced the usage of the Flak 18 gun as a direct infantry support weapon. By the end of the war the 88-mm guns had performed far more missions as an anti-tank and direct-fire Field Artillery gun than as an anti-aircraft gun. During the war German 88-mm guns were involved in 377 combat engagements, only 31 were against enemy aircraft. On the other side the use of the 88-mm in close proximity to the enemy made it vulnerable to infantry fire. Casualties among the legion's 88-mm gun batteries in the Spanish Civil War were second only to those among the bomber pilots.

In early 1937 in the fighting around Malaga, a battery of 88-mm guns was assigned to support an infantry brigade. Bad weather grounded the main bomber force, but the assault succeeded, mainly because of the concentrated and accurate fire of the supporting 88-mm guns. Flak 18 batteries were by the nationalist army at the Battle of Ebro, used for direct fire against pillboxes and for indirect fire in the advance towards Barcelona.

Following the Spanish Civil war, more Flak. 36 models arrived in 1943 (88 guns 88/56 mm Flak-36) and since 1943 they were manufactured under licence in Trubia under the denomination FT 44 (about 200 guns).

Allied
The Flak 36 guns were briefly issued in late 1944 to the American 7th Army as captured weapons. The 79th Field Artillery Battalion (Provisional) was formed from personnel of the 79th and 179th Field Artillery Groups to fire captured German artillery pieces at the height of an ammunition shortage. Similarly, the 244th Field Artillery Battalion was temporarily equipped with a miscellany of captured German 88mm guns and 105mm and 150mm howitzers.

Yugoslavia
During the civil war in Yugoslavia in the 1990s, various Flak guns were used, mainly by the naval artillery of the Yugoslav People's Army (JNA). The Serbian Army (VJ) also used Flak carriages mounted with double 262 mm rocket launch tubes from the M-87 Orkan MLRS, instead of the 88mm gun. It was capable of deploying cluster bombs, as well as anti-personnel and anti-tank mines, at up to 50 km. Only a few were built in mid-1993, the entire project was generally regarded as unsuccessful.

Comparison to other anti-aircraft guns
The Flak 18 was not as powerful as its Italian or Allied counterparts. As an anti-aircraft gun it fired a 9.2 kilogram (20 lb) shell at a muzzle velocity of 790 m/s (2,600 ft/s) to an effective ceiling of 7900 m (at maximum 10600 m). Although this was useful against US daylight raids, which typically flew at 7600 m, many aircraft could fly higher than its maximum effective ceiling. In comparison, the British 3.7 in Mark 3 fired a 13 kg projectile at 790 m/s (2,600 ft/s) to an effective ceiling of 10600 m, and the American 90 mm M1 fired a 10 kg shell at 820 m/s (2,700 ft/s) to the same height, while the Italian Cannone da 90/53 fired a 10.33 kg projectile at 830 m/s to an effective ceiling of 12000 m. The Allied weapons' capabilities were augmented by the introduction of proximity fuses, which vastly increased their effectiveness, especially after the introduction of jet-engined aircraft. The Allies' and Italian weapons were heavier and less mobile, with the Allied weapons being almost useless for ground fire until numerous modifications were carried out. While the US and Italian 90 mm would go on to serve as powerful anti-tank guns, they were by no means as universally deployed as tank-killers as was the German 88.

Pak 43 and KwK 43


At the time Rheinmetall developed the Flak 41, Krupp's tried to compete with their 8.8 cm Gerät 42 proposal, but it was not accepted for production as an anti-aircraft gun. Krupp continued development, resulting in the dreaded 8.8 cm Pak 43 anti-tank gun and 8.8 cm KwK 43 tank gun.

Pak 43 (an abbreviation of Panzerabwehrkanone 43) used a new cruciform mount with the gun much closer to the ground, making it far easier to hide and harder to hit. It was also provided with a much stronger and more angled armour shield to provide better protection. All versions were able to penetrate about 200 mm of armour at 1,000 m, allowing it to defeat the armor of any contemporary tank. The standard armament of the Tiger II, the KwK 43 tank gun, was essentially the Pak 43 externally modified to fit into a turret. There were also self-propelled versions of the gun, including the lightly-armored Nashorn and, later, strongly-armored Elefant and Jagdpanther tank destroyers.

Guns using the 88×571R mm cartridge

 * 8.8 cm Flak 18 Had a new semi-automatic breech, making it a high velocity gun. It entered production in Germany in 1933 and used the Sonderanhänger 201 trailer. its weight was seven tonnes. Its rate of fire was 15 to 20 rounds per minute. It was later fitted with a gun shield to protect the crew when engaging ground targets. It was produced by Krupp.
 * Mod 1938 II: Approximately 50 guns were modified so a single man could adjust the elevation and traverse.
 * 8.8 cm Flak 36 Entered service 1936–37. It used the redesigned trailer Sonderanhänger 202 which enabled a faster time into action from the move. The SdAnh 202 had twin wheels on two similar carriages. It could engage ground targets from the traveling position. Its weight was seven tonnes. Its rate of fire was 15 to 20 rounds per minute. It was produced by Krupp. It was subsequently fitted with a shield to protect the crew when engaging ground targets.
 * 8.8 cm KwK 36: The main gun of the PzKw VI Ausf. E (Tiger I) tank. Despite its designation, some classify it as a parallel development with very similar specifications rather than a derivative of the Flak 36. 2001gun88mmwiki.jpg, Duxford]]
 * 8.8 cm Flak 37: It was an updated version of the Flak 36, the main difference being Übertragungser 37 (a data transmission system). It was produced by Krupp.

Guns using the 88×855R mm cartridge

 * 8.8 cm Flak 41: This was a weapon developed and produced by Rheinmetall-Borsig to be used with a 855 mm cartridge case. It was fitted to the existing Sonderanhänger 202 as standard and entered service in 1943. The barrel was at first designed as three-section with a length of 74 calibers, and then redesigned to dual-section with a length of 72 calibers.

Guns using the 88×822R mm cartridge

 * 8.8 cm Gerät 42: Was a new Krupp design to compete with the Flak 41; it did not enter service as an anti-aircraft gun. Further development of the weapon led to the Pak 43 anti-tank gun.
 * 8.8 cm Pak 43: An anti-tank model developed from Krupp's 8.8 cm Gerät 42. With a new gun carriage, the Sonderanhänger 204 was developed by Krupp and manufactured in different versions, including the KwK 43, by at least Dortmund Hoerder-Hüttenverein, Henschel, Weserhütte and Fr. Garny. It had a 71 caliber barrel and a 822 mm cartridge case.
 * 8.8 cm Pak 43/41: The Pak 43 was mounted on a single axle split-trail field gun carriage which was produced as a stop-gap measure due to the scarcity of materials. Its weight was 4.9 tonnes.
 * 8.8 cm Pak 43/1: The Pak 43 mounted in the Nashorn tank destroyer.
 * 8.8 cm Pak 43/2 The Pak 43 mounted in the Ferdinand/Elefant tank destroyer. It was occasionally referred to as the "StuK 43/1".
 * 8.8 cm Pak 43/3 and 43/4: The Pak 43 mounted in the Jagdpanther tank destroyer. It had a falling wedge breech block.
 * 8.8 cm KwK 43: The Pak 43 modified as a tank gun. It was the main gun of the Tiger II heavy tank. It also had a falling wedge breech block.

Weapons of comparable role, performance and era

 * QF 3.7-inch AA gun : contemporary British anti-aircraft gun, firing a heavier (28 lb) shell
 * Cannone da 90/53 : contemporary Italian anti-aircraft gun
 * 90 mm Gun M1 : contemporary US anti-aircraft gun
 * 85 mm air defense gun M1939 (52-K) : contemporary Soviet anti-aircraft gun

External links and further reading

 * History of the 88 mm series of guns
 * US Military Intelligence document on the 88 mm gun
 * The New 88 and Its Carriages
 * Detailed examination of the effect of 88 mm FlaK on B-17 and B-24 bombers
 * Technical Manual German 88 mm Antiaircraft Gun Materiel - US War Department, 29 June 1943
 * Extract from "Handbuch für den Flakartilleristen" - Die 8.8 cm – Flak 1939