The idea of strengthening guns infantry units by the self-propelled artillery appeared in Germany in the mid-thirties. It was forged into action shortly after the end of the war against Poland in 1939.
During the French campaign Wehrmacht infantry received support from the 150 mm guns combined with PzKpfw I chassis known as Bison I as well as armed with 75 mm short-barreled cannon, assault guns - Sturmgeschűtz III. Both proved to be very effective especially in combat in built-up areas and during breaking the enemy’s fortified defensive positions. Thus began the story of Sturmartillerie, the final product of which on one hand became famous StuG III and StuH 42, on the other: the so-called Brummbär – Sturmpanzer IV assault tank.
Origins of Sturmpanzer IV
The initiator of the creation of the German mobile artillery was General Erich von Manstein, in 1935, holding the post of army chief operating branch - Operationsabteilung. Even then, he expressed the view that in addition to strengthening the armored arm of rebirthing after the so-called Versailles Crisis German armed forces, headed by Adolf Hitler, in the form of tanks, to ensure the lightning war – Blitzkrieg, will not be possible without the proper assistance to infantry units. About how important problem it was, the German staff officers discovered during the Polish Campaign in September 1939. It turned out that the conventional, towed artillery, largely horse-drawn yet repeatedly fails to keep up with the assaulting forward infantry especially the motorized one.
The first, basically improvised solution was the 15 cm Sturminfanteriegeschűtz 33 heavy infantry gun, which in the German army has been used since 1927 mounted on the PzKpfw I Ausf. B light tank hull. This vehicle was called Bison I. It was sent into action in the six selected assault companies assigned to six armored divisions and proved well in combat during the battles in France in the late the spring of 1940. An extension of this idea has become a launch at the end of 1941 the production of another variant equipped with the same type of main armament – Bison II, based on a modified (extended) chassis of another German light tank – PzKpfw II. There were twelve vehicles of this type sent to fight in North Africa the following year.
That time, the dynamic development of Sturmartillerie became reality. Between 10 and 22 September 1942 the special meeting in Hitler’s headquarters was held, during which the decision of preparing as soon as possible the next group of infantry support full-tracked vehicles but this time based on the chassis of PzKpfw III medium tank. Their weapons, just as before, has become a proven 150 mm infantry gun. This time it was placed in an enclosed armored superstructure (both Bison I and Bison II was characterized by an open combat compartment). Sturminfanteriegeschűtz 33 (other name: Sturminfanteriegeschűtz III) embarked on the Eastern Front in the next month. These vehicles, which in the total number of twenty-four pieces were assigned to two assault battalions: Sturmgeschutz-Abteilung 177 and Sturmgeschutz-Abteilung 244 and a heavy self-propelled guns company of Lehr-Bataillon XVII were a direct ancestor of the machine which is the subject of this book.
In October 1942 it was decided to create another variant of the assault tank, as more and more people began calling tracked armored vehicles armed with gun caliber 150 mm, this time based on the chassis PzKpfw IV. There were designers of Altmärkisches Kettenfabrik (Alkett) factory in Berlin-Spandau who had to deal with the project. It was pointed out that the vehicle should not have straight as its predecessor, but the sloping armor superstructure. At the same time the bureau of Pilsen (Czechoslovakia) company Skoda was recommended to develop the new type of weapon that could effectively replace the worn-out 15 cm SIG 33. At the same time there was an interesting suggestion to equip the new child of German Sturmartillerie with heavier armament such as 210 or 220 mm assault mortar. It was minister of industry and armaments, Albert Speer himself, who was supervising the work. Due to the growing demand for front-line units, as well as increasing production problems in Germany themselves, it was decided that the chassis for the new machine will be derived from a few series of PzKpfw IV tanks, being sent to the long-term repairs.
Sketches of a new vehicle were ready on October 2, 1942. Twelve days later, Adolf Hitler reviewed it, indicating that the first batch of new self-propelled guns, made out roughly sixty pieces were to be ready not later than in the beginning of spring of the following year. February 7, 1943 r. Skoda representatives presented to Führer the wooden mockup of a tracked combat vehicle armed with a new assault howitzer, specially developed for it: 15 cm Sturmhaubitze 43 L/12. It was mounted in a tall, angular superstructure situated in the place where the turret of PzKpfw IV was originally installed.
The new vehicle was designated Gerät 581 166 Sturmpanzerwagen 604/16 Sonderkraftfahrzeug Alkett Sturminfanteriegeschűtz auf PzKpfw IV mit kardanischer Aufhängung. The first six vehicles, based on the overhauled chassis were finished in March. During the conference two months later it was decided that the machine would receive a new, shorter name, associated with the howitzer variant, in which was armed: Sturmpanzer 43 or, at the same time, according to the chassis: Sturmpanzer IV. The first fully completed vehicle was officially presented for the first time May 14, 1943 at the training ground in Orzysz (East Prussia) – Truppenübungsplatz Arys. Baptism of fire was soon to pass. The important not only for Wehrmacht battle of Kursk appeared on the horizon.
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