the Möbelwagen prototype armed with four 20 mm cannons and with the side panels raised, source: Flickr.com with the permission of the publishing user, edited

From roughly the middle of 1943, the problems with anti-aircraft defence of German ground forces escalated sharply and urgently needed to be addressed. The Luftwaffe was no longer able to provide adequate fighter cover for German units dispersed across an enormous front. The only ground-based defensive means available at the time were towed anti-aircraft guns or self-propelled guns mounted on half-track tractors. The anti-aircraft tank Flakpanzer I was already out of the picture — all examples had long since been lost in combat — and the Flakpanzer 38(t) was still under development.

Origins of the Flakpanzer

Tank units in particular lacked a self-propelled anti-aircraft weapon capable of keeping pace with them across even the most difficult terrain. The designers considered a number of possible solutions, but time pressure forced them to base the new vehicle on some existing platform. The chassis of the Panzer III, which by that point had no future as a fighting tank, was one option — but it proved not entirely suited to mounting an anti-aircraft weapon. The choice therefore fell on the more robust chassis of the Panzer IV. The programme to develop an anti-aircraft tank on this basis produced, over the following years, several different vehicles of this type. The first of them was the vehicle known by the combat name Möbelwagen.

The original army specification from the summer of 1943 called for armament in the form of the 2 cm Flakvierling 38, a combination of four rapid-fire 20 mm cannons. The design of the new vehicle was entrusted to Krupp.

Design description

The turret was removed from a standard Panzer IV tank. The original fighting compartment below the turret was significantly widened outward, extending almost to the edges of the track mudguards. It also received a new front wall, which no longer featured an opening for the hull machine gun. The hole left by the removed turret was plated over, creating a platform on top of the original fighting compartment for the installation of the weapon. Four hatches were cut into the floor of the new fighting space. The two hatches at the front served as entry and exit points for the driver and radio operator seated there. The hatches at the rear of the floor gave access to the space beneath the gun, where most of the ammunition was stored. To protect the crew, tall flat walls were erected around the gun on all sides. The top of the fighting space was left open so that the crew could easily spot and hear approaching enemy aircraft and open fire on them.

a late-production series Möbelwagen with the side panels raised, source: Flickr.com with the permission of the publishing user, edited

The walls of the fighting space consisted of double armour plates 2 × 12 mm thick. The walls could be folded down to the horizontal position so as not to obstruct the gun's movement when engaging ground targets. With the side panels folded down, the gun and its crew were protected only by the weapon's own gun shield. The side walls also had an intermediate position — they could be tilted outward by around 35 to 40 degrees, which extended the gun's range of movement while still keeping it within an enclosed — and therefore protected — compartment. When the sides were tilted out, the upper corners of the front and rear walls could be further "widened" by folding out pentagonal armour flaps.

First prototype

The first prototype of the new anti-aircraft tank was completed in September 1943 and demonstrated to General Guderian on 16 October. He was satisfied with the vehicle's characteristics and ordered series production to begin no later than April 1944. The prototype's official designation was 2cm Flakvierling 38 auf Fahrgestell PzKpfw IV. It went down in history, however, under a different and unofficial name, which it owed to its appearance. With the side panels fully raised, the vehicle resembled an enormous box, earning it the nickname Möbelwagen — literally a furniture van or removal lorry.

The Flakvierling 38 with which the prototype was armed consisted of four automatic 20 mm Flak 30 anti-aircraft cannons. The assembly had an impressive theoretical rate of fire of 1,800 rounds per minute (4 × 450). The practical rate of fire was "only" around 720 to 800 rounds per minute, but even that is a rather formidable figure.

a series Möbelwagen with the side panels folded down; the vehicle commander is holding a coincidence rangefinder for determining the target's distance, source: Flickr.com with the permission of the publishing user, edited

Series vehicles

Although the prototype met the army's expectations, a decision was taken in December 1943 to change the project. The series anti-aircraft tank was to be rearmed with the 37 mm Flak 43 cannon. Krupp accordingly modified the vehicle's design to meet the new specification and began series production in March 1944. The original order was for only 100 Möbelwagens, but it was eventually expanded and production continued until March 1945, with a total of 240 vehicles built.

Beyond the armament, the prototype and the later series Möbelwagens differed from one another only in minor details. Worth mentioning, for instance, are the small closeable circular openings in the side walls of the fighting space, which served as firing ports for small arms. The supplier of the folding armour panels for the fighting compartment was Deutsche Eisenwerke of Duisburg. The first 20 armoured superstructures — as on the prototype — consisted of double plates 2 × 12 mm thick. The next 25 armoured superstructures were again double-plated, but this time only 10 mm per plate (i.e. 2 × 10 mm). From the 46th example onwards, the armour was produced as a single homogeneous plate 25 mm thick. On later vehicles a closeable circular opening appeared in the front wall of the lower hull compartment, apparently serving as a firing port for a machine gun. The side armour plates also lost their angled upper sections and became straight.

The series Möbelwagen received the official designation Flakpanzerkampfwagen IV (3,7 cm Flak 43), with the ordnance code Sd.Kfz. 161/3. The main gun could be elevated between –7 and +90 degrees, making it perfectly capable of engaging ground targets as well. Traverse was a full 360 degrees. The Flak 43 had a theoretical rate of fire of 250 rounds per minute, though the practical rate was only 150 rounds per minute. The ammunition supply for the gun comprised 400 rounds, of which 80 were armour-piercing. Compared to the prototype version with its four 20 mm cannons, the series tank had a lower rate of fire, but a greater effective range and more destructive effect on target.

a series Möbelwagen captured by the Allies; note the non-standard cutout in the front plate of the fighting compartment, apparently made by the crew themselves in a field workshop, source: Flickr.com, Public domain, edited

The Möbelwagen inherited its powerplant along with the chassis from the Panzer IV tank — a twelve-cylinder petrol engine, the Maybach HL 120 TRM, with a displacement of 11.9 litres and a maximum output of 300 horsepower. The six-speed Zahnradfabrik SSG 76 Aphon gearbox was likewise carried over from the original fighting tank. The Möbelwagen weighed 25 tonnes and was capable of a maximum speed of 38 km/h. Its range was approximately 200 km on road and 130 km cross-country. The crew consisted of six men: driver, radio operator, commander, loader and two gunners.

Combat deployment

Möbelwagens were organised into anti-aircraft platoons of either four or eight vehicles and attached to various armoured formations. Their primary task was to protect combat units from direct attacks by enemy fighters or fighter-bombers, particularly during movement. These vehicles fought from June 1944 until the very end of the war, on both the Eastern and Western Fronts. Combat experience showed that the folding armour arrangement of the fighting compartment was not an ideal solution. If the crew travelled with the side panels raised, they needed time to fold them down before opening fire. If, on the other hand, they left the panels down during movement, the crew were completely unprotected and fully exposed to attack from the ground. It is therefore no surprise that subsequent Flakpanzers were built with a rotating armoured turret.

One thing I was unable to establish anywhere is how the crew raised the folded side panels back to the vertical position. At a rough estimate, a single side armour plate measured approximately 2.8 metres in length and just under a metre in height. At a thickness of 25 mm and taking into account the standard density of steel, a single such plate must have weighed over half a tonne. If the armour was raised by hand, the entire crew presumably had to put their backs into it — and even then, those six soldiers must have had their hands very full indeed.

Technical data

ARTICLE
CONTENTS:

ORIGINS

DESIGN DESCRIPTION

FIRST PROTOTYPE

SERIES VEHICLES

COMBAT DEPLOYMENT

TECHNICAL DATA