Sturmpanzer IV Brummbär was german armoured infantry support gun based on the Panzer IV chassis. Also known as Sturmpanzer 43 or Sd Kfz 166.

History

Since the StuG assault guns were used more and more as tank destroyers, the infantry lacked a support vehicle. Moreover, during the battles in Stalingrad, it turned out that the previous assault guns did not have sufficient firepower in the city battle. The available vehicles were gapped fillers such as the SiG 33 B on Sturmgeschütz III chassis or like the Sturmpanzer I on converted chassis antiquated tanks, both equipped with a 15 cm howitzer sIG 33. The StuG III, on the other hand, was unable to bring down an average city building with two or three shots, as was now demanded. On June 9, 1941 it was therefore demanded to mount a 15 cm sIG 33 on a heavily armored chassis. Therefore, it was decided to construct a large-caliber on the chassis of the Panzerkampfwagen IV. The result was Sturmpanzer IV, called "Brummbär" by the allied forces. The German troops cut off this name with "StuPa". He received the Sturmhaubitze 43 from the sIG 33 in a caliber of 150 mm and was thus ideally suited for the task of infantry support. The design was strongly oriented to the highly successful StuG III. On 20 October 1942, after seeing Alketts plans Hitler demanded that 40 - 60 Sturmpanzer IV be built as soon as possible. On 7 February 1943 the first wood models were presented to him in original size. Convinced of the troops' need for these vehicles, he ordered an investigation to see if and how destroyed and damaged Panzerkampfwagen IV could be converted. The production was approved. A first series of 40 vehicles should be completed by 12 May, another 20 vehicles should follow. By April 1943, the vehicle had been designated Gerät 581 – Sturmpanzerwagen 604/16 (Alkett) sIG auf Panzer IV mit kardanischem Fahrwerk. In April 1943 the type number Sd.Kfz. 166 have been awarded. On Hitler's instructions, the vehicle was not assigned to the artillery as the assault-guns, but fell into the responsibility of the Panzerwaffe, and he also ordered the name Sturmpanzer. The most common designations are the Sturmpanzer IV or the Sturmpanzer 43. On the basis of repaired Panzerkampfwagen IV chassis, the Heereszeugamt Wien set up twenty vehicles in April 1943, another 40 followed in May. A major revision took place for the second and third constructions of which 60 vehicles were produced between November 1943 and May 1944 on the basis of new chassis of the Nibelungenwerke in Sankt Valentin. The superstructure was made in the Eisenwerken Oberdonau and Böhler in Kapfenberg. The Austrian companies Saurer and Simmering-Graz-Pauker were responsible for the production. From spring 1944 the development and production responsibility was transferred to the Deutschen Eisenwerke in Duisburg. The first vehicles produced there were delivered from June 1944 onwards. The first tests showed a weight of 28.2 tons (including 5 men, crew and 38 rounds of ammunition for the 15 cm sIG 33), so the engine and chassis were heavily overloaded. After initail run, the production of a long term series went ahead in November 1943 and continued until the end of the war. The 60 vehicles of the early production were equipped with the 15-cm-Sturmhaubitze 43 L/12. Starting from December 1944 the 15 cm Sturmhaubitze 43/1 L / 12 was used. Compared to the previous model, this was lighter in weight. From the late version, an MG 34 was installed in the front of the superstructure.

The following two types of ammunition were used in Sturmpanzer IV: Igr 38 FES - 38 kg HE grenade against buildings, bunkers and field positions Igr 39 H.I/A - a 25 kg shell against fighting armored vehicles Total production: 306 guns.

Specifications

crew	5
armor	front: 100 mm, sides:  50 mm, rear 20 mm, top: 20 mm, bottom: 10 mm
main armament	15 cm StuH 43 L/12 (32 rounds)
secondary armament	1 x MG34 or MG42 (600 rounds)
weight (kg)	28200
length (mm)	5800
width (mm)	2860
height (mm)	2450
track base (mm)	3520
ground pressure (kg/cm2)	0,85
engine	Maybach HL 120 TRM, 300 hp at 3000 rpm. 12 cylinder, water-cooled, gasoline 11867 cm3
transmission	ZF SSG 76 Aphon, 6 forward, 1 reverse
fuel capacity (l)	470
fuel consumption (l) (road / off road)	250/350
range (road km/ off-road km)	210/130
speed (km/h)	40
number of links per track	99 (type: Kgs 61/400/120)
ground clearance (mm)	400
trench crossing (mm)	2200
vertical obstacle (mm)	600
fording ability (mm)	1200
climbing ability (degrees)	30
turning circle (mm)	5920
manufacturer	Nibelungenwerke
chassis numbers	80501 - 84400, 86601 - 87100, 89101 - ?

Bibliography and sources

• Nashorn, Hummel, Brummbär, Waffen-Arsenal 3 (german)
• Markus Jaugitz: Der Sturmpanzer IV "Brummbar",  Waffen-Arsenal 160 (german)
• George Parada, Krzysztof Mucha: Sturmpanzer IV Brummbar, Kagero Photosniper 12 (Polish/English )
• Janusz Ledwoch: Hummel, Nashorn, Brummbär - Wydawnictwo Militaria 16
• Waldemar Trojca, Markus Jaugitz: Sd.Kfz.166 Sturmpanzer "Brummbär" Vol.1, Trojca 4
• Tom Cockle: Battle on Two Fronts 1944-45, Concord Armor At War Series 7048
• Samir Karmieh, Krzysztof Mucha, Łukasz Gładysiak: Sturmpanzer IV Brummbär, Kagero Photosniper 3D
• Hiromu Araki: Achtung Panzer No. 4