8.8 Cm Flak 18/36/37/41 - Flak 18, 36 and 37

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 calibres, leading 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 casing would be thrown backward by levers, and a cam would 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 armoured vehicles.

Widespread production started with the Nazi rise to power in 1933, and 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. Further, the high muzzle velocity and large calibre made it an excellent long-range anti-vehicle 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 while in an emergency mode when still on wheels and without grounding outriggers, but with a very limited traverse and elevation. For normal emplacement, one single-axle bogie was detached from the front outrigger, one from the rear outrigger, and side outriggers were hinged from vertical position to the ground, which was estimated at a minimum of 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, and 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 Flak 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-armour purposes. The fact is all 8.8 cm Flaks were capable of the dual role.