Category: WW2 German SPAAGs

German Reich (1938-1945)
Self-propelled Anti-Aircraft Gun – At Least 3 Converted

The Schulfarhzeug 1-5b. Serie/La.S. mit MG 34/42 Zwillingssockel 36 (Eng. training vehicle 1-5. Series of agricultural vehicles with MG 34/42 dual mount 36) was a Panzer I training variant that mounted anti-aircraft weapons. It was a field conversion that first appeared in 1938 and was last seen in Denmark in 1945. The vehicle lacked protection and was most likely only used for training soldiers in the anti-aircraft role.

History of the First Light Anti-Aircraft Vehicles 

The concept of protecting troops from air attacks and air raids was not new to the Second World War. Already during the First World War, anti-aircraft vehicles, mostly trucks with machine guns or small guns, were introduced to deal with support planes. During the Interwar years, Germany was forbidden from building any tanks or AFVs due to the Versailles Treaty.

In 1930, the German Army gradually started to rearm and also began to develop and build more AFVs. After the Nazis took over Germany in 1933, the Treaty of Versaille was completely disregarded. With this general rearmament, the concept of self-propelled anti-aircraft vehicles was brought up again. It was introduced to many types of vehicles with different armaments. Alongside the Sd.Kfz.10/4 (a small half-tack with a 2 cm Flak gun), there was also the Kfz.4 Truppenluftschutzwagen (Eng. air defense vehicle) introduced in 1938. It was a 4-wheeled cross-country personal carrier featuring the Einheitsfahrgestell I (Eng. unitary chassis I) with a Zwillingslafette 36 (dual mount 36) and machine guns. The idea behind the Kfz.4 was to have a small reliable vehicle that could effectively defend itself and the troops against low-flying aircraft with its dual machine guns. However, these vehicles would be produced in smaller numbers, as the unitary chassis I was used for more important vehicles. However, the Kfz.4 was not only the unitary chassis I, but this designation was used to describe many different motor vehicles using the Zwillingslafette 36. It was also mounted on cars and horse drawn trailers and even in fixed positions.

Making Use of an Old Chassis

The Panzer I Ausf.A and B were introduced as the first real German serial-produced tank in 1935. Even though it was obsolete by 1939, it still saw service throughout the war. Next to the regular Panzer I which was intended for combat, a number of Panzer I chassis would be reused as training tanks. These Schulwagen (Eng. training vehicles) were open-top chassis without armament and superstructure. but maintained the engine deck. They also often had railings.

The Schulwagen saw service from 1934-1945 as training tanks. However, at some point, even the Schulwagen became obsolete. Therefore, many Schulwagen were converted into new roles. One of these conversions was the anti-aircraft role.

Production and Conversion 

It is unknown how many Flakschulwagen Is were built, but photographic evidence suggests that at least 3 different vehicles were built. Based on photographic evidence, the first Flakschulwagen I appeared around 1938 during pre-war training. The vehicle used the Panzer I Ausf.B chassis, and, unlike the others, it used only a singular anti-aircraft MG 34 on a monopod mount placed in the crew compartment.

It is unknown when the second Flakschulwagen I was built, but photos show the vehicle in 1943 and in 1945. It had the dual mount anti-aircraft MG 34 and was based on the Panzer I Ausf.A chassis.

The third and final confirmed Flakschulwagen I was built after 1942 due to its dual mount MG 42, which was first introduced in 1942.

Name

The vehicle was a field conversion and therefore never received a real designation. Furthermore, it is unknown how the troops referred to it. Therefore, a name can only be drawn from the combination of the parts. The chassis was the Panzer I training school tank referred to as Schulfahrzeug 1-5.Serie/La.S. and the gun, the Zwillingssockel 36. This designation would be: Schulfahrzeug 1-5b. Serie/La.S. mit MG 34/42 Zwillingssockel 36 (Eng. training tank 1-5b. Series/agricultural tractor with MG 34/42 Zwillingssockel 36). The article will use a more simplified version of the designation: Flakschulwagen I (Eng. anti-air training vehicle I).

Design

This modification was based on both the Panzer I Ausf.A and B chassis. Both versions were in principle quite similar, the main difference being that the Ausf.B version was longer with a modified engine compartment (including a new engine) and had one more road wheel in the suspension.

Hull

The Panzer I hull, like nearly all German tank designs, could be divided into three sections: the front part where the transmission was placed, the central crew compartment, and the rear-positioned engine. The overall construction was made out of several armor plates welded together, with a firewall separating the engine compartment and the crew compartment.

The later Ausf.B’s hull design did not change much aside from the rear hull, which was extended to be able to fit the new suspension and larger engine. Furthermore, the extension allowed for additional space for cooling air and the tow coupling to be relocated to the rear. The rear armor cover was redesigned to fit the new engine. It was made higher at the rear for the air intake to cool the engine. The air was drawn through the radiator and blown out of a grill placed at the rear right-hand side of the engine deck. A new split hatch was placed above the engine for easy access. Lastly, the two exhaust pipes, which on the Ausf.A were located on the mudguards, were removed and a single muffler with extra armor protection was fixed to the rear side. The Flakschulwagen I’s hull design appears to be unchanged from the original Panzer I tank configuration.

Suspension 

The suspension on the Flakschulwagen I was unchanged. The Panzer I Ausf.A’s suspension consisted of one front sprocket wheel, three return rollers, one idler wheel, and four road wheels on each side. While the first/front road wheel was a single wheel, the second and third road wheels were paired in a leaf spring suspension. The fourth road wheel was also mounted on a suspension cradle connected to the idler wheel. The idler wheel was partially connected to the fourth road wheel and touched the ground, which would later turn out to be a significant problem, as the steering of the tank was severely impaired. In addition, the first wheel used a coil spring mount with an elastic shock absorber in order to prevent any outward bending

The suspension upgrade is probably the most visual change from the Ausf.A to Ausf.B and is often used to distinguish between them. The reason for these changes was to upgrade the overall mobility and mainly the steering. With the Ausf.A, the tank, whenever it was being steered, had to also move the idler wheels, which inhibited and slowed down the steering process. This would also increase the chance of the tank throwing a track. Furthermore, a new lengthened suspension would help with a more stable ride and more stability whilst firing.

On the Ausf.B, a fifth road wheel and a fourth return roller were added. The connection between the fourth road wheel and the idler wheel was cut and the fourth wheel was instead connected in a pair to the new fifth road wheel. The second and third were also connected in a pair, whilst the first one was independent. The idler wheel was raised and its crank arm was mounted in a housing. Track tension was done by rotating the idler wheel’s crank arm.

Engine

The engine on the Ausf.A was the Krupp M 305 four-cylinder giving out 60 hp @ 2,500 rpm. The maximum speed with this engine was 37 km/h. The later Ausf.B version received a completely new engine. This was necessary as the Krupp M 305 proved to be unreliable and prone to overheating. The new engine used was the water-cooled Maybach NL 38 Tr, able to supply 100 hp @ 3,000 rpm. The tank’s speed increased to 40 km/h. The fuel was located in two tanks, with one holding 82 liters and the other 62 liters, both on the right side, separated from the crew compartment.

With the removal of the upper superstructure and turret, a great deal of weight was removed from these modified vehicles. The weight of the Panzer I Ausf.A was 5.4 and the Ausf.B 5.8 tonnes. According to P. Chamberlain and H. Doyle (Encyclopedia of German Tanks of World War Two – Revised Edition), the weight of the Panzer I Ausf.B modified with the upper superstructure that was used for training was 4 tonnes. This reduction in weight of over a tonne would probably have affected the overall drive performance of these vehicles, possibly being slightly faster than the original tank configurations. Given the lack of information about the Flakschulwagen I’s overall drive performance, this could be considered as speculation at best.

Superstructure

The Flakschulwagen I vehicles were based on modified Panzer I chassis intended to be used as training vehicles. These were never provided with a superstructure, and instead, the crew was completely exposed to weather and to enemy fire. Given the role that these vehicles were to perform, this was not an issue. Metal bars were usually added on top of the hull to act as a safety measure to prevent one of the crew from accidentally falling off the vehicle.

Armor

The modified Panzer I Ausf.A and B armor was quite thin. The Panzer I’s front hull armor ranged from 8 to 13 mm. The side armor was 13 mm, the bottom 5 mm, and the rear 13 mm. The armor was made of rolled homogenous hardened plates with a Brinell hardness of 850. It was welded and formed the body of the superstructure and hull. Although not protected from even small caliber anti-tank guns, it could provide protection against small arms fire and SmK bullets (steel-cored rifle bullets). The later Ausf.B did not receive any changes to the overall armor thickness.

The crew operating the main armament on the Flakschulwagen I was completely exposed, as no gun shield was ever used on the light machine gun mount.

Armament

This vehicle was armed with either two 7.92 mm MG 34 or MG 42 machine guns. Both were designed as a general purpose machine gun intended to fulfill several different roles, including acting as a light machine gun, heavy machine gun (placed in a fixed mount), secondary armament of armored vehicles, etc. They were excellent designs with a great rate of fire, 800 to 900 rounds per minute on the MG 34 and 1,200 on the MG 42. While these could be operated by one man, ideally, two men would be needed, with the second acting as an ammunition carrier. The MG 34 was introduced just prior to the Second World War, but proved to be rather expensive to build. As a replacement, the much cheaper MG 42 was developed and put into service after 1942. After that point, the MG 34 was only used as the secondary armament for tanks or other armored vehicles, while the MG 42 was issued to infantry formation.

When these two and some older machine gun designs were used in the anti-aircraft role, they were simply placed on a three-leg mount. There was a simple connector point that merged the machine gun to this mount. It had a 360° traverse, so that any aircraft that came into sight could be targeted. To be able to effectively engage flying targets, an especially designed sight was also used.

The use of this mount was quite common and was the basic line of anti-aircraft defense for many infantry units. Nonetheless, something with more firepower that could be used by infantry and other units was needed. Early in the war, the Germans introduced the Zwillingslafette 36. This was basically a simple pedestal mount with a 360° traverse armed with either two MG 34s or MG 42s. To the back, the gunner seat was located, while the mounting for the two machine guns was placed on the front. The two machine guns were positioned parallel to each other. In the middle of this mount, a machine gun sight specifically designed for engaging air targets was added.  While this mount was usually placed inside various vehicles, it was also towed in trailers or even employed as a static emplacement. With its two 7.92 mm caliber machine guns, realistically, it could only do minor damage to enemy aircraft. That said, destroying an enemy aircraft was not always the goal of anti-aircraft units, as even forcing the enemy to stop an attack was considered a success. Despite German anti-aircraft units being supplied with larger caliber weapons, this mount would remain in service up to the end of the war. Both machine guns usually used a 75-round capacity drum magazine. The precise ammunition load of these modifications is unknown.

While the precise installation of the Zwillingslafette 36 inside the Flakschulwagen I is not clear given the lack of sources, it was probably simple in nature. The bottom of the mount was likely bolted down the Flakschulwagen I’s hull bottom. This way, it could be easily removed if the weapon mount was damaged or the vehicle needed to be modified for other purposes.  The Zwillingslafette 36 appears to have had a full 360° traverse in this vehicle.

Interestingly, at least one Flakschulwagen I was armed with a single MG 34 machine gun or possibly even some older model. Due to the photograph’s poor quality, it is not clear if the mount was an improvisation or taken from other vehicles that were in the German service. The latter option seems to be more plausible, as the Germans used a single machine gun mount on a number of their reconnaissance vehicles, such as the a href=”https://tanks-encyclopedia.com/ww2/nazi_germany/sdkfz-221-222-223.php”>Sd.Kfz.221, for example.

Crew

It is unclear how large the crew of this modification was. Given the rather small size of the Panzer I, it would be limited to a few only. This likely included the driver, who would be positioned on the hull’s left side; the commander/gunner, who would operate the machine guns; and, lastly, possibly a loader, who would help to load the two machine guns or act as an extra spotter. Given the vehicle’s limited interior space, the remaining crew would have to stand on its side fenders in order to help with the ammunition supply.

Doctrine and Organization

How the Flakschulwagen Is were actually used is not known. There are two ongoing theories. One states that the Flakschulwagen Is were used as training vehicles for anti-aircraft instruction. This theory is supported by the first Flakschulwagen I with the single MG 34 used during pre-war training. Furthermore, the dual mount MG 34 was also stationed in Germany, providing further evidence. The second theory states that the Flakschulwagen Is were taken over from training battalions to real divisions and actually saw combat. This theory is supported by the dual mount MG 42 Flakschulwagen which was deployed in the Soviet Union in 1943. However, due to the limited protection for the crew, the first theory is more likely.

In what exact divisions the vehicles were organized is also not known. The regular training vehicles were part of training schools and later divisional training battalions. This would also be the part where the Flakschulwagen would be organized within. If the vehicles were to have been sent into combat, they would most likely have been organized similarly to the Kfz.4 air defense car, since these were the units that received the Zwillingssockel 36. The Kfz.4s were organized into 4 anti-aircraft sections with one vehicle each, within an anti-aircraft platoon within the HQ unit of the tank’s regiment.

Service Life

The service life of the Flaschulwagen I is not recorded anywhere and can only be deduced by using photographic evidence.

The first Flakschulwagen I with the single MG 34 was used as a training vehicle. It is most likely that the vehicle did not see combat service and was presumably lost at some point throughout the war.

The second Flakschulwagen I most likely appeared around 1943 due to the dark yellow camouflage, which was introduced in said year. This vehicle can be seen used as a training vehicle in Germany and it later ended up in Denmark in 1945.

The third Flakschulwagen I also presumably appeared around 1943, due to its camouflage. In the photos, the vehicles can be seen dug in, possibly used in a stationary role as a defense position of an HQ unit. The vehicle was photographed in the Soviet Union, which would suggest the vehicle was part of an actual combat unit.

Other Flakpanzers Based on the Panzer I Chassis

During the early stages of the war, the Germans modified small quantities of Panzer I Ausf.A tanks as ammunition carriers. These lacked any kind of defensive weapons to protect themselves from either ground or air targets. For this reason, from March to May 1941, some 24 Panzer I Ausf.A were modified as self-propelled anti-aircraft vehicles.

In addition to the Flakpanzer I armed with the 2 cm Flak 38, a few were built with the triple 1.5 or 2 cm MG 151 Drilling. These (the precise numbers are unknown, it could have been only a single vehicle) were built by placing the new weapon mount inside the crew compartment, but without the upper superstructure. The existing photo shows it was built using a Panzer I Ausf.B chassis. Not much is known about this modification. As the MG 151 Drilling was employed in greater numbers at the war’s end, it is likely that this was a last-ditch effort to increase the Panzer I’s firepower by any means possible when there was nothing else available. There is also the possibility that this vehicle was also made using a Panzer I training vehicle.

Conclusion

The Flakschulwagen I was quite an unusual and generally poorly documented vehicle. It was created using the obsolete Panzer I chassis and armed with the two machine gun mount creating a vehicle that was likely used for crew training. The ever-increased reliance on anti-aircraft vehicles to provide protection against enemy aircraft would explain the need to create the Flakschulwagen I.

Using photo evidence, it seems at least one of them saw frontline combat to some extent. Its combat performance would be limited at best, as it had virtually no armor to protect the exposed crew and only possessed weak armament. Sadly, the fate of any of these vehicles is unknown.

specifications
Dimensions (L-W-H)	4.61 x 2.13 x 1.12 m
Weight, battle-ready:	Around 3 tonnes
Crew	3 (driver, commander/gunner, loader)
Propulsion	Ausf.A: Krupp M 305 4-cylinder air-cooled, Ausf.B: Maybach NL 38 TL  6 cylinder water-cooled petrol
Speed	37 km/h  (on roads) / 25 km/h (cross-country)
Range	140 km, cross-country: 93 km
Armament	Zwillingslafette 36, 2x 7.92 mm MG 34 and MG 42,
Armor:	Up to 13 mm
Trench crossing capability:	1.40 m
Ground clearance:	29.5 cm

 

Sources

• P. Chamberlain and H. Doyle (1978), Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
• Walter J. Spielberger (1982), Gepard The History of German Anti-Aircraft tanks, Bernard
• D. Miller (2001), 20th Century Guns, Greenwich Editions
• Ian V. Hogg (1975), German Artillery of World War Two, Purnell Book Services Ltd.
• T. L.Jentz and H. L. Doyle (1998), Panzer Tracts No.12 Flak selbstfahrlafetten and Flakpanzer
• T. L.Jentz and H. L. (2010), Doyle Panzer Tracts No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects
• H. Doyle (2005), German military Vehicles, Krause Publications
• Leo WG. Niehorster German unit organization of WW2
• http://www.kfzderwehrmacht.de/

 

 

German Reich (1943)
Self-Propelled Anti-Aircraft Gun – 141 to 152 Built

As in the later years of the Second World War, the Luftwaffe (Eng. German Air Force) began losing control over the sky and the German ground forces were subjected to increased Allied ground attack raids. Panzer divisions were especially affected by the lack of air fighter cover as they were always at the center of the most intense fighting. While the Germans already had copious amounts of half-tracked SPAAGs of different calibers and weights, they had a significant flaw of being themselves vulnerable to the planes they were meant to hunt. A tank-based anti-aircraft vehicle, a Flakpanzer (Eng. Anti-aircraft tank), could solve this problem, as it would have the armor to resist most aircraft armament. By 1943, the Flakpanzer IV was developed. Due to their rather slow development, the Germans were forced to introduce a temporary solution. This would lead to the creation of the Flakpanzer 38(t) in November 1943.

Search for an Anti-Aircraft Tank

In the early stages of the Second World War, the responsibility for covering the ground forces from enemy air attacks was solely in the hands of the Luftwaffe. This did not mean that the panzer divisions and other ground forces were left without the means to respond to such threats. The Germans employed a series of anti-aircraft weapons, from standard machine guns provided with anti-aircraft mounts to more dedicated weapons, including the 2 cm, 3.7 cm, and 8.8 cm anti-aircraft guns. These were mostly towed weapons quite well suited to slow infantry formations.

Panzer divisions were units whose greatest combat potential was combined firepower and excellent mobility. Once the enemy line was pierced, they would rush into the enemy’s rear, causing great havoc and preventing them from forming an organized retreat. Towed anti-aircraft guns did not work well in this concept, so a weapon system with better speed was more desirable. The Germans employed a series of half-tracks for this purpose, such as the 2 cm Sd.Kfz.10/4 and the 2 cm Flakvierling 38 Sd.Kfz.7/1 armed vehicles.

Half-tracks armed with anti-aircraft guns proved vital in providing the panzer divisions with protection from enemy aircraft attacks, but they themselves were far from perfect. Probably their greatest drawback was the lack of protection. Whilst some would receive armored cabins, this was not enough.

Developing a mobile self-propelled anti-aircraft vehicle based on a tank chassis was deemed to be more effective. One of the first attempts was to mount a 2 cm Flak 38 on a modified Panzer I chassis. This vehicle could be considered more of a field modification than a properly designed vehicle.

In 1942, several different anti-aircraft tanks were proposed. As these were mainly to be built using chassis that were not yet in production, such as the Panzer II Luchs and Leopard chassis, nothing came of them. In any case, the already overburdened German industry had enough problems keeping up with demand. As such, adding another chassis was deemed unnecessary.

The simpler solution was to use a Panzer IV chassis for this project. The Luftwaffe officials initiated this project in June 1943. Once again, Krupp was responsible for its realization. This would lead to the creation of the 2 cm Flakvierling auf Fahrgestell Panzer IV prototype. This was basically a Panzer IV with a modified superstructure with four large folding sides. As the armament was deemed insufficient, a stronger 3.7 cm anti-craft gun was to be installed instead.

Development

The beginning of production of the new Flakpanzer IV armed with the 3.7 cm anti-aircraft gun would be delayed, and, as such, a temporary solution was needed. Other chassis were considered as substitutes, but, due to various reasons, these could not be adopted for the Flakpanzer project. For example, both the Tiger and Panther chassis were desperately needed in their original tank configuration. Panzer III chassis could have been reused for this proposal, but due to high demand for the StuG III, it also could not be used. Luckily for the Germans, they had the Panzer 38(t) in their inventory.

The TNH – LT vz.38 tanks as it was originally known, were developed and built by the Czechoslovak ČKD company (Českomoravská Kolben Daněk) in the second half of the 1930s. Production of the vz.38 began in late 1938 but, by the time of the German annexation of Czech territory, not a single tank was handed over to the Czech Army. Germany captured many brand new vz.38 tanks and, in May 1939, a delegation was sent to the ČKD factory to examine their operational potential. The Germans were so impressed with this tank that it was quickly introduced into Wehrmacht service under the name Panzer 38(t) (the ‘t’ stands for Tschechoslowakei, Czechoslovakia in German). The ČKD factory was completely taken over for the needs of the German Army under the new name BMM (Böhmisch-Mährische Maschinenfabrik).

The Panzer 38(t) was built in relatively large numbers, seeing combat action from the invasion of Poland to the end of the war, and was considered an effective tank for its class. But, from late 1941 onwards, it was obvious that it was becoming obsolete in the role of first-line combat tank. The Panzer 38(t) chassis, on the other hand, was mechanically reliable and was highly suitable for other purposes, a fact which the German exploited to the maximum by developing a series of auxiliary vehicles like the anti-tank or self-propelled artillery.

Given the availability and reliability of  Panzer 38(t) chassis, the  Inspektion der Panzertruppen 6 / In 6 (Eng. Armored Troops’ Inspection Office 6) issued an order to the BMM to begin developing an anti-aircraft vehicle in October 1943. Given the urgency of the project, the BMM engineers simply decided to resume the already produced Marder III Ausf.M chassis which was also used for self-propelled artillery armed with the 15 cm gun known as Grille. This helped to speed up the development time, and also made the whole production easier, as there was no major need for creating new tooling equipment. After inspection of this prototype by German military officials, an order was given for a production of 141 (or 162 depending on the sources) such vehicles as quickly as possible. This small manufacturing order, at odds with the high demands for such a vehicle, can be explained by the fact that the production of the more powerful Flakpanzer IV was expected to start in early 1944.

Designation

This vehicle was designated as Panzerkampfwagen 38 für 2 cm Flak 38 (Sd.Kfz.140) Ausf.L. Slight variation of this designation may be found in the sources. For example, authors V. Francev and C. K. Kliment (Československá obrněná vozidla 1918-1948) describe this vehicle as Flakpanzer 38(t) auf Selbstfahrlafette  38(t) Ausf.M. Today, it is generally referred to simply as Flakpanzer 38(t). This article will use this designation due to simplicity only.

Interestingly, it is also described by its supposed nickname ‘Gepard’. This is likely a post-war addition, as there is no evidence to support that the German used this nickname for the  Flakpanzer 38(t).

Production

Although the German Army wanted as many Flakpanzer as possible, only a limited number of Flakpanzer 38(t)s were actually completed. This is primarily due to the single 2 cm Flak 38 often being described as having weak combat performance by the second half of the war and the beginning of the production of the much better Flakpanzer IV vehicles. In total, some 141 Flakpanzer were built by BMM from November 1943 to February 1944 when production ended. The following production numbers are according to T. L. Jentz and H. L. Doyle in Panzer Tracts (No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects).

Flakpanzer 38(t) production
1943
November	50
December	37
1944
January	41
February	13
In total	141

 

Walter J. Spielberger (Gepard The History of German Anti-Aircraft tanks), mentions that a production order for 162 such vehicles was initially made. Ultimately, only 152 were completed and the remaining 10 chassis were reused for the self-propelled artillery Grille.

Design

The Hull

The new Flakpanzer 38(t) was built using the standardized Marder III Ausf.M version. It consisted of a Panzer 38(t) chassis that was heavily modified. The originally rear-positioned engine was moved to the center of the vehicle, creating the new rear-positioned fighting compartment. To the right front side, the fully enclosed driver compartment was located, and in front of it, the transmission unit was placed.

The glacis armor that protected the front positioned transmission was placed at a high angle. It retained the large hatch door which provided the crew with easier access to the brake and transmission assemblies (in case of emergency and repair). It was protected by an extended ‘U’ shaped splash ring. Usually, spare track links were added to the left side of the front plate, as a replacement for damaged tracks and as improvised (but limited) extra armor protection. The hull and the remaining parts of this vehicle body were constructed using armored plates riveted or to a smaller extent welded together.

The Suspension and Running Gear

The suspension of the Flakpanzer 38(t) was mostly unchanged in comparison to that of a normal Panzer 38(t). It consisted of four large road wheels with split rubber tires. The use of large-diameter wheels was meant to reduce wear on the rubber tires. These wheels were connected in pairs and were suspended using semi-elliptical leaf springs units. In addition, there was a front drive sprocket, rear idler, and two return rollers per side. The only visible difference was the reduction of the number of return rollers from four in total to only two (with one on each side).

The Engine and Transmission

The Flakpanzer 38(t) was powered by a Praga AC 6-cylinder water-cooled 150 [email protected],600 rpm engine. With a weight of around 9.8 tonnes, this vehicle could reach maximum speeds of 42 km/h and 20 km/h cross-country. The operational range was 185 km and 140 km cross-country. The fuel load of 220 liters was stored in two fuel tanks placed under the engine and protected by an armored plate. A large ventilation grill was placed on the right side of the engine compartment. In addition, a long exhaust pipe ran from the right side up to the rear of the vehicle.

The Superstructure

The Flakpanzer 38(t) received a completely new superstructure. It could basically be divided into three sections with the driver’s compartment at the front, the enclosed engine compartment placed in the middle, and the fighting compartment in the rear.

While on a standard Panzer 38(t) the driver and the radio operators were positioned parallel to each other, on the Flakpanzer 38(t), the radio operator position was moved to the new rear fighting compartment. The driver remained alone in an especially built compartment located on the front right side of the vehicle’s bow. The driver entered and exited the vehicle through a top split hatch and had two observation ports in front and on the right side.

The engine compartment was located in the center of the vehicle. It was mainly protected using simple flat armor plates. On top of this compartment, two larger hatches were placed for the crew to access the engine itself. Interestingly, two square-shaped metal beams were placed on top of the engine compartment. Their purpose is unspecified in the sources.

Lastly, the fighting compartment was located at the rear of the vehicle, and housed the main weapon, which was enclosed with eight shield plates. In order to accommodate the new gun platform, the compartment was greatly extended over the vehicle’s rear fenders. As it was open-topped, it allowed the crew members to have a better view of the environment and search the sky for enemy aircraft. The upper part of each of these eight armored shields could be folded down. This was necessary in case the crew had to engage ground targets or low-level attack aircraft. Enemy air targets that were high in the sky could be engaged with the folding sides fully raised. When these shield plates were folded down, the only protection for the crew was the gun shield itself. The whole installation was far from perfect as the crew would need some time to fold down these shields when engaging targets at a lower height, time that could be vital for the vehicle and the crew’s survival. This was probably the main reason why on vehicles that were used by frontline troops the armor plates were often folded down. Given the small Panzer 38(t)’s chassis, a fully protected and rotating turret could not be installed. Inside the fighting compartment, various necessary tools and equipment were stored (mainly ammunition, spare barrels, the crew’s personal belongings, radio equipment, etc.).

The Armament

The Flakpanzer 38(t)’s main armament consisted of a 2 cm Flak 38 anti-aircraft cannon. This was a weapon intended to replace the older 2 cm Flak 30, which it never actually did. It was designed by Mauser Werke, incorporating many elements of the Flak 30 with some internal changes, such as the addition of a new bolt mechanism and return spring. It was designed to shoot down low-flying aircraft, but it was also found to be very effective when used against unarmored ground targets. The 2 cm Flak 38 was also used extensively as a mobile-mounted weapon on several German vehicles, such as half-tracks (Sd.Kfz.10/4), trucks, and even armored trains.

Unlike other vehicles that were equipped with this gun, the installation of the 2 cm Flak 38 inside the Flakpanzer 38(t)’s fighting compartment required some modifications. The original Flak 38 three-legged mount was removed and the gun was placed on a hexagonal-shaped metal base inside the fighting compartment.

While the gun could be traversed 360° with the armor plates raised up, its elevation would be limited in this case. To use the gun effectively, the upper fighting compartment plates had to be lowered down. When lowered, the elevation of this gun was -10° to +90°. The maximum effective range was 2 km against air targets and 1.6 km against ground targets. The maximum rate of fire was between 420 and 480, but the practical rate of fire was usually between 180 to 220 rounds. The ammunition load consisted of around 1,040 rounds. It usually included 720 high-explosive and 320 armor-piercing rounds. In reality, this number may be different depending on the combat need or availability of ammunition. Author Walter J. Spielberger (Gepard, The History of German Anti-Aircraft Tanks) mentions that the ammunition load consisted of 540 high-explosive and the same amount of armor-piercing rounds. To avoid the spent cartridges flying around the fighting compartment, the original net basket was retained. The ammunition was usually stored under the gun mount and the sides of the fighting compartment. Besides the crew’s personal weapons, mostly pistols and MP 40, no secondary weapon was provided for self-defense.

The crews were frontally protected by the gun’s own shield. The gunner also had another smaller gun shield in front. In addition, a head protective shield was placed for the gunner (just above the seat). Some vehicles, for unknown reasons, did not have either the gun or the gunner’s shields.

The Armor Protection

Sources such as T. L. Jentz and H. L. Doyle (Panzer Tracts No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects development and production from 1942 to 1945) give us the following information about this vehicle’s armor thickness. The front glacis was 10 mm thick at a 65° angle and the lower hull front was 20 mm at a 15° angle. The top hull armor was 8 mm thick flat armor and the driver’s compartment was protected by all-around 20 mm of armor placed at a 20° angle. The side armor was 15 mm thick, the rear was 10 mm at a 55° angle, and the bottom was 8 mm. The superstructure armor consisted of 10 mm thick plates placed at different angles. The front plates were angled at 20°, side 25°, upper and lower 17°, while the rear plates were placed at 25°.

Other authors, such as D. Nešić (Naoružanje Drugog Svetsko Rata-Nemačka) provide completely different armor thickness figures. The front hull armor was 25 mm thick, sides 15 to 19 mm, top 10 mm, rear 12 mm, and the driver’s compartment 25 mm thick. The front and side armor of the superstructure was 25 mm and the rear 15 mm thick. Author W. Oswald (Kraftfahrzeuge und Panzer) lists the armor thickness as 10 to 50 mm.

Being an open-topped vehicle and with low armor thickness, crew protection was on a very low level. Camouflage and a well-selected field position were essential for survival. Another consequence of being an open-topped vehicle was thatthe crew was also exposed to weather conditions. A canvas cover could be placed over the vehicle but it limited the crew’s view of the surroundings.

The Crew

Despite being a rather small vehicle, the Flakpanzer 38(t) had a fairly large crew of four. This included the driver, who was positioned in the hull of the vehicle. The remaining crew was placed inside the small fighting compartment to the rear of the vehicle. It consisted of the commander/gunner, loader, and radio operator. Sources on the topic disagree, as some mentioned that the crew actually consisted of five crew members. Author Walter J. Spielberger (Gepard The History of German Anti-Aircraft tanks) mentions that this vehicle had a crew of five: driver, commander/gunner, two loaders, and a radio operator There are even pictures that offered potential proof of this. The reasons why the number of crew is different in the sources or in the old photographs is not clear. A possible explanation is that due to shortages of manpower the Germans had in 1944, out of necessity, some vehicles were operated by a smaller crew. Another possibility is that some units may have decided to add another crew member to act as a additional plane spotter or to fulfill similar roles.

Organization and Unit Distribution

The Flakpanzer 38(t)s were grouped into Panzer Flak-Zügen (Eng. anti-aircraft tank platoons). Each of these platoons consisted of 12 vehicles. These were mainly allocated to Wehrmacht (Eng. Army) and some to SS Panzer Divisions. This included the 2nd, 21st, and 26th and Lehr Panzer Divisions, 90th and 29th Panzer GrenadierDivision, followed by the 9th, 10th, and 12th SS Panzer Division, and lastly Hermann Goering Panzer Division.

In May 1944, the Flakpanzer 38(t)s of the 9th and 10th SS Panzer Division were given to the 1st and 2nd SS Panzer Divisions. Finally, in mid-September 1944, Flakpanzer 38(t)s were allocated to the 17th SS PanzerGrenadier Division. Interestingly, these were originally intended for the 10th SS Panzer Division but for unspecified reasons were allocated to the previously mentioned unit.

In Combat

The majority of produced Flakpanzer 38(t)s would see service on the Western Front in 1944 and 1945. Some 84 were present when the Allies invaded France in June 1944. With the overwhelming Allied air superiority, the available Flakpanzer 38(t) vehicles realistically could do little to effectively protect the German units. Despite this, the  Flakpanzer 38(t)s managed to bring down numerous Allied aircraft. For example, the crews of one such vehicle from the 12th SS Panzer Division alone managed to shoot down 5 enemy aircraft. This division’s main focus was the defense of Caen. By 9th July, when the Allies finally broke the German defenses, the 12th SS Panzer Division was left with  25 Panthers, 19 Panzer IVs, and a few Flaks. This means that by this point they had likely lost all of its Flakpanzer 38(t) vehicles.

In December 1944, the Flakpanzer 38(t) participated in the last, large German offensive in the West, known as Operation Northwind. The 17th SS Panzer Grenadier Division had six  Flakpanzer 38(t) and four Flakpanzer IV Wirbelwind in its inventory by the end of December 1944, most were fully operational by that point.

Some 48 Flakpanzer 38(t)s were sent to Italy as part of the 26th Panzer Divisions, 29th and 90th PanzerGrenadier Division, and by the Panzer Division Hermann Goering. Very few Flakpanzer 38(t)s may have seen combat on the Eastern Front, in units such as the 2nd Panzer Division, which in December 1944 had only 3 Flakpanzer 38(t).

The effectiveness of the 2 cm gun in combat conditions is often criticized to be weak by the standards of 1944. Not all support this notion, as some sources, such as the T. L. Jentz and H. L. Doyle (Panzer Tracts No.12 Flak selbstfahrlafetten and Flakpanzer) mention a report made by Major Petri dated from 30th January 1945, in which he states: “…In my opinion, the problem of whether to use 2 cm or 3.7 cm anti-aircraft guns has been decided completely in favor of the 2 cm. The Jabo [German term used to describe Allied attack aircraft] is the Mistvieh. He attacks at low heights. In every case always at an elevation where the 2 cm is effective. Most Jabo kills are credited to the 2 cm. When bombers attack in saturation bombing raids, they are always at heights that can’t be reached by the 3.7 cm.” 

Surviving vehicles

Today, at least two badly damaged Flakpanzer 38(t)s can be seen at the André Becker Collection in Belgium and in the Battle of Normandy Museum, Bayeux, France.

Conclusion

The Flakpanzer 38(t) was a mixed bag solution. On the one hand, it provided better-armored protection (but still relatively lightly protected) and mobility than other German anti-aircraft vehicles that were in service at the time. On the other hand, the weak armament, combined with the fact that the armor plate protecting this gun had to be lowered significantly to operate, reduced its combat effectiveness. By the standards of 1944 and 1945, the firepower of the single 2 cm gun was deemed too weak, but despite it, it was still effective against soft ground targets and a number of enemy aircraft were often shot down. The Panzer 38(t)’s chassis was mechanically reliable and was deemed adequate for this modification, as this vehicle was considered a stopgap solution and not many were produced. While it did not have any major impact on the war, it gave the Germans crew something to fight back against the ever-increasing Allied air supremacy.

Specification
Size (L-W-H):	4.61 x 2.13 x 1.177 m
Weight	9.8 tonnes
Crew	4 to 5 (driver, commander/gunner, loader, and radio operator)
Engine	Praga AC 6-cylinder water-cooled 150 hp ​​@ 2,600 rpm
Speed	42 km/h  / 20 km/h (cross-country)
Range	185 km / 140 km/h (cross-country)
Armament	2 cm Flak 38
Armor	8 to  20 mm

 

Sources

• T. Anderson (2020) The History of the Panzerwaffe, Osprey Publishing
• P. Chamberlain and H. Doyle (1978) Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
• Walter J. Spielberger (1982). Gepard The History of German Anti-Aircraft tanks, Bernard & Graefe
• D. Terlisten (2009) Flakpanzer IV Wirbelwind and Ostwind, Nuts and Bolts
• Y. Buffetaut (2018) German Armor in Normandy, Casemate
• H. Walther (1989) The 12th SS Panzer Division HJ, Schlifer Publisher
• H. Meyer (2005) The 12th SS The History of the Hitler Youth Panzer Division: Volume One, Stockpile Book
• H. Meyer (2005) The 12th SS The History of the Hitler Youth Panzer Division: Volume Two, Stockpile Book
• Ian V. Hogg (1975) German Artillery of World War Two, Purnell Book Services Ltd.
• T. L.Jentz and H. L. Doyle (1998) Panzer Tracts No.12 Flak selbstfahrlafetten and Flakpanzer
• T. L.Jentz and H. L. Doyle Panzer Tracts (2010) No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects
• Flakpanzer 38(t) auf Selbstfahrlafette 38(t) Ausf.M (Sd.Kfz.140), AFV Interiors Web Magazine.
• H. Doyle (2005). German Military Vehicles, Krause Publications
• S. J. Zaloga (2010) Operation Nordwind 1945, Osprey publishing
• P. Chamberlain and H. Doyle (1978) Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
• W. Oswald (2004) Kraftfahrzeuge und Panzer, Motor Buch Verlag
• H. C. Doyle and C. K. Kliment (1979) Czechoslovak Armoured Fighting vehicles 1918-1945, Bellona
• V. Francev and C. K. Kliment (2004) Československá obrněná vozidla 1918-1948, Nase Vojsko
• P. C. Adams (2010) Snow and Steel The Battle of the Bulge 1944-45, Oxford University Press

• N. Szamveber (2013) Days of Battle Armoured Operations North Of The River Danube, Hungary 1944-45, Helion & Company

 

German Reich (1943)
Self-Propelled Anti-Aircraft Gun – Unknown Number Built

As the Luftwaffe (German Air Force) lost control of the skies over Germany in the second half of the Second World War, it could no longer provide sufficient protection against Allied aircraft. Panzer divisions were especially affected by the lack of cover from fighter aircraft because they were always at the center of the most intense fighting.

The Germans already had copious amounts of half-tracked Self-Propelled Anti-Aircraft Guns (SPAAG) of different calibers and weights (Sd.Kfz.10/4, Sd.Kfz.6/2, Sd.Kfz.7/1, etc.). As these vehicles had very limited or no armor, they were vulnerable to enemy fire either from the ground or the air. The crew needed better protection from small arms fire and shrapnel. A tank-based anti-aircraft vehicle, or Flakpanzer, could solve this problem, as it would have thick enough armor to resist most ground-based attacks with the exception of larger caliber guns. It would also provide some protection against air attacks, but even tanks could be destroyed by air ground-attack fire. An open-topped Flakpanzer’s best defense against air threats was its anti-aircraft gun.
The word “Flakpanzer” comes from combining the abbreviation for Fliegerabwehrkanone (literally Aircraft-Defense-Cannon) and Panzer (Tank).
The first attempt at producing such a vehicle was the Flakpanzer I, which was built only in limited numbers and was more of an improvisation rather than a purpose-built vehicle. The later 20 mm-armed Flakpanzer 38(t) had insufficient firepower and armor protection and was more of a temporary solution. Later, the Möbelwagen (based on the Panzer IV tank chassis) was armed with the more powerful 3.7 cm Flak 43 anti-aircraft gun, which solved the problem with the weak main armament, but was not without its defects. The Möbelwagen needed too much time to set up for firing and was thus ineffective against a sudden enemy attack. A Flakpanzer that could respond without preparation was more desirable, and the first such vehicle was the Flakpanzer IV 2 cm Flak 38 Vierling, commonly known as the ‘Wirbelwind’. While it was produced in small numbers and was generally viewed as an effective vehicle, the 2 cm caliber was deemed too weak by the late stages of the war. For this reason, a much stronger 3.7 cm Flak 43 was installed in a new turret and the ‘Ostwind’ (Eastwind) was born.

Three Flakpanzers from the same family based on the Panzer IV chassis. From left to right, they are the Ostwind, Möbelwagen and the Wirbelwind. Source

History

By 1943, it had become apparent that the Luftwaffe was losing control of the skies, and that the need for a Flakpanzer was dire. For this reason, the German Heer (German Army) took the first steps in developing new Flakpanzer designs. Given the long development time necessary to bring a new chassis to maturity and the shortage of available production capacity, it was decided to amend existing designs to fulfill the Army’s needs. The simpler and more logical solution was to simply reuse already produced chassis. The Panzer I and II were outdated or used for other purposes. The Panzer 38(t) was used in small numbers as a temporary solution, but it was needed for anti-tank vehicles based on this chassis and, in any case, it was deemed inadequate for this task due to its small size.
The Panzer III tank chassis was used for the production of the StuG III and thus not available. The Panzer IV and the Panzer V Panther were considered next. The Panzer IV tank chassis was already in use for several German modifications, so it was decided to use it for the Flakpanzer program. The Panzer V Panther was, for a short time, considered to be used as a Flakpanzer armed with two 37 mm anti-aircraft guns, but mostly due to the high demand for tank hulls, the project never went beyond a wooden mock-up.
The first Flakpanzer based on the Panzer IV tank chassis was the 2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV. It did not receive any production orders but the prototype was modified and upgraded with the larger 3.7 cm Flak 43 (known as the Möbelwagen to its crews) and around 240 of this version were produced. The Möbelwagen had sufficient firepower to destroy enemy planes and the crew was protected by armored plates on four sides, which needed to be dropped down to use the gun effectively. The Möbelwagen needed time to set up for action and was therefore not a success.
It was apparent that a Flakpanzer with a fully rotating turret, enclosed on all sides and open-topped, was needed. For this reason, in early 1944, Generaloberst Guderian, Generalinspekteur der Panzertruppen (Inspector-General for Armored Troops), gave In 6 (Inspektion der Panzertruppen 6/ Armored Troops Inspection Office 6) direct orders to begin work on a new Flakpanzer.
The main requirements for such a vehicle were:

• The turret should be fully traversable (360°)
• The new turret should have three or four crew members
• The crew operating the anti-aircraft gun should be well protected and it should be open-topped so as to give the crew a better view of the skies and because of the smoke produced by the guns
• The turret traverse mechanism should be simple
  The main weapons (it had to have at least two guns) should have a minimum effective range of 2000 m, with enough ammunition to operate efficiently in a combat situation
• The height must be lower than 3 m
• Radio equipment was important
• From this requirement, two new projects were developed: the Wirbelwind armed with four 2 cm guns and the later Ostwind, armed with one 3.7 cm gun.

Name

There are several names given to this vehicle, which include Flakpanzerkampfwagen IV 3.7 cm Flak 43, Leichte Flakpanzer mit 3.7 cm Flak 43 auf Panzerkampfwagen IV or, much simpler, Flakpanzer IV/3.7 cm. It is most well-known today under its Ostwind nickname and this is very common in many sources. The origin or even if it was an original German designation is not clear, as none of the sources give a specific explanation of the origin of this name. This article will use the Ostwind name mostly for simplicity but also because of its common use in the literature.

First Prototype

While the Wirbelwind was an effective vehicle, its main drawback was the lack of effective range and the limited destructive power of the smaller caliber 2 cm rounds. The 3.7 Flak 43 had much greater range and destructive firepower and, for this reason, a decision was made to begin developing a new Flakpanzer armed with this weapon. To speed up the development time, the Ostwind was constructed using the same principle as on the Wirbelwind. The gun, enclosed in an all-round protected (except the top) turret was added on a Panzer IV chassis (with some modifications). Originally, to save time, it was intended to reuse the Wirbelwind turret, but mounting the larger 3.7 cm Flak 43 in it was not possible, so a new design had to be made.
The prototype was completed by Ostbau Sagan in July 1944. The man in charge of designing and building the Ostwind project was Lt. Graf von Seherr-Thoss. This man was also responsible for the Wirbelwind program development. At his disposal, he had a small team of 80 workers who were mostly recruited from Panzer-Ersatz und Ausbildungs-Abteilung 15. The Ostwind, similar to the Wirbelwind, was to be built by the German Army itself, without the inclusion of any commercial firms. Lt. Graf von Seherr-Thoss and his team reused an older refurbished Panzer IV Ausf.G chassis and added a simple new six-sided turret (made of mild steel) with 10 mm thick plates in which the 3.7 cm Flak 43 with its crew were placed.

The Ostwind prototype front view. The man in the picture is the Ostwind chief designer Lt. Graf von Seherr-Thoss. Source: Pinterest

The Ostwind prototype was built using an older Panzer IV Ausf.G tank chassis (Ser.Nr. 83898) and a mild-steel turret. This vehicle would actually see combat during late 1944. Source
The Ostwind prototype, together with the Wirbelwind, were transported in late July 1944 to Bad Kuhlungsborn on the Baltic Coast for live-firing tests of the guns. During these tests, only a limited number of shots were fired by the Ostwind, less than 130 rounds in total. Observers from In 6 reported positive results for both these two vehicles and that the whole construction was feasible and without major problems. The only modifications that were required for the Ostwind was an increase in the size of the turret and improving the traverse system.
Based on this report, on 16th August 1944, Generaloberst Heinz Guderian ordered the Army Ordnance Office Wa I Rü (WuG 6) to arrange the construction of 100 new Ostwinds. The chassis would be provided by Krupp-Grusonwerk, the turrets by Roehrenwerke and assembly would be carried out by Deutsche Eisenwerke AG-Werk Stahlindustrie. At the end of 1944, Ostbau Sagan also became involved in producing the Ostwind.
Due to the rapid Allied advance in France following D-Day, the development of the Ostwind was temporarily stopped and the prototype was sent to France in late September 1944. A few days later, it was reported to have successfully participated in combat despite its mild steel turret. Although the combat results were promising and there was an urgent need for such a vehicle, the development and production of the Ostwind were slow and, by the end of 1944, there was little to no progress. The reason for the slow development process was the deterioration of the German war industry due to Allied bombing actions. In late 1944, Deutsche Eisenwerke A.G. Werk Stahlindustrie came under heavy bomber attack by the Allies and had to be evacuated. This was also the case with Ostbau Sagan, which was relocated in January 1945. The production of the first Ostwind vehicles began at the end of 1944 or early 1945, depending on the source.

Construction

As already mentioned, the Ostwind prototype was built using a Panzer IV Ausf.G tank chassis. For the production version, it was decided to use new Panzer IV Ausf.J chassis provided by Krupp-Grusonwerk. Whether this plan was ever fully implemented or if reused damaged Panzer IV chassis were provided by Krupp-Grusonwerk instead is not known. In Ostbau Sagan, the Ostwinds were built using any available chassis returned from the front, due to the high demand for new Panzer vehicles from the German Army.
The suspension and running gear were the same as those of the original Panzer IV, with no changes to its construction. It consisted of eight pairs of small road wheels on each side, with each two pairs suspended by leaf-spring units. There were two front drive sprockets, two rear idlers and six to eight (depending on the model used) return rollers in total (three to four on each side). The engine was the Maybach HL 120 TRM that produced 265 hp at 2600 rpm, but, according to Panzer Tracts No.12, the engine was modified to put out 272 hp at 2800 rpm. The design of the engine compartment was unchanged. The maximum speed was 38 km/h and, with a fuel load of 470 l, the operational range was 200 km.
The upper tank hull was unchanged from the original Panzer IV. The driver’s front observation hatch and the ball-mounted hull machine gun remained the same as well. In some sources, it is mentioned that the Ostwind production model had a Tiger turret ring installed instead of the standard one. This information is also mentioned in the Panzer Tracts No.12 book, ‘Flak Selbstfahrlafetten and Flakpanzer’ (H.L. Doyle and T. J. Jentz) from 1998. However, in the new version from 2010, it is mentioned that the Ostwind turret was placed on an unchanged Panzer IV tank chassis without mentioning the Tiger turret ring. In addition, author D. Terlisten stated that this was planned by the Germans but never implemented on any production vehicle. So it highly likely that the Ostwind was never equipped with the larger Tiger turret ring, and that the whole thing was misinterpreted by some author after the war. It is possible to understand why this confusion could arise as the Ostwind was built at the end of the war, a period from which much documentation is missing.
For the installation of the main weapon, two metal beams were welded inside the Panzer IV hull to make a stable platform on which the 3.7 cm Flak was placed. For crew protection, an open-topped turret was provided. The new turret had a much simpler design than that of the Wirbelwind, constructed using only 12 larger armored plates (in contrast to 16 used on the Wirbelwind). This made the new turret much easier and faster to produce. This six-sided turret received the Keksdose (cookie tin) nickname. The prototype used a smaller turret, but to provide the crew with more working space, a somewhat larger turret was to be used on the production vehicles. For turret movement, a simple mechanism was provided. A steering rod was used to connect the Flak 43 traversing mechanism and the Panzer IV turret ring. This allowed the crew to move the turret by using the gun traverse. While more precise details regarding the turret construction are not known due to a lack of information, we can assume that it used a ring-shaped turret base welded to the hull top, with added ball bearings to help with the rotation, similar to the Wirbelwind. On the production Ostwinds, the lower part of the turret front had an additional pyramid-shaped sheet of armor welded to it. Its purpose was to provide additional protection against any possible ricochet (from smaller caliber rounds) in the direction of the vehicle hull. The larger turret also had one drawback, as it made it difficult to open the engine compartment. To do so, the turret had to be rotated 90°.

The new turret provided the crew with sufficient protection against low caliber rounds. Being open-topped, it provided a good view of the surrounding area and the skies. Source
The maximum hull armor thickness was 80 mm thick on the front, the sides were 30 mm, the rear 20 mm and the bottom and top armor were only 10 mm thick. The armor thicknesses noted here are for the late-build Panzer IV versions. Due to a lack of proper information and the chaotic state that Germany was in during late-1944 and early-1945, it is possible that some older chassis were used for this modification too. The new turret was protected by 16 mm of armor all-round, placed at a 30° angle. A number of sources note that the armor thickness was 25 mm. According to W. J. Spielberger (Gepard The History of German Anti-Aircraft tanks) the armor thickness was originally 16 mm, but later, during production, it was increased to 25 mm.
The main weapon used was, as already stated, the 3.7 cm Flak 43. Although sharing the same 3.7 cm caliber as the earlier Flak 18, 36 and 37 models, the newer Flak 43 (built by Rheinmetall-Borsig) was a completely different weapon. The primary goal of this design was to be simple to operate and easy to produce. It had a new gas-operated breech mechanism which was loaded with a fixed loading tray with eight-round clips. There was also a Flakzwilling 43 version with two guns mounted on the same carriage. In order to be installed in the new turret, some modifications were needed. The lower part of the carriage and the original gun shield were removed. In addition, the spent ammo basket was smaller due to the turret size. Only the small rectangular shield in front of the gun was left in order to cover the front embrasure opening. The Flak 43 could rotate a full 360°, with a range of gun elevation between – 10° to + 90°. The maximum rate of fire was 250-300 rounds per minute, but 150-180 was the more practical rpm. It is not clear, but it is estimated that between 400 to 1,000 rounds of spare ammunition were carried inside the vehicle. With the muzzle velocity of 820 mps, the maximum effective ceiling was 4,800 m. The upper right front armor plate had a small hatch that could be opened to allow the gunner to see and engage ground targets. The spare barrel (or barrels) were kept in a box mounted on the right side of the vehicle’s hull. For self-defense, the crew could rely on the hull-mounted MG 34, retained from the Panzer IV design, and their personal weapons.

The Flakzwilling 43 had two 3.7 cm guns, but other than that it was the same as the single barrel version. Source
The crew consisted of the commander, gunner, radio operator, driver and the loader. But, according to Panzer Tracts No. 12-1 (2010), there were actually two gunners. The driver and radio operator were placed in the vehicle hull. For the radio operator, the Fu 5 and Fu 2 radio equipment were provided. In addition, he also operated the hull-mounted machine gun. The remaining three (or four) crew members serving the main weapon were placed inside the new cramped turret.
Due to changes made so that the gun could fit the turret, the gunner’s pedals had to be put far back. The gunner had to sit with his legs very close to his upper body. As the open-topped turret exposed the crew to the elements, a canvas cover was provided for protection.

In this view, the position of the crew in the turret is observable. To the gun’s right is the gunner, behind it, the commander, and to its left, the loader. Source: Pinterest

Illustration of the Flakpanzerkampfwagen IV 3.7 cm Flak 43 ‘Ostwind’ produced by Tank Encyclopedia’s own David Bocquelet

Production

In early September 1944, Deutsche Eisenwerke A.G. Werk Stahlindustrie (from Duisburg) received orders for the assembly of 100 Ostwind vehicles. The Panzer chassis were to be provided by Krupp-Grusonwerk, with 30 chassis each month. The first five chassis were to be ready no later than mid-October. The turrets were to be provided by Roehrenwerke with first 10 in September followed by 30 in each month until the end of the year. According to the initial plans, Ostwind production would begin in November with 35 vehicles, followed by 30 in December and 10 in January 1945.
Due to many delays (Stahlindustrie had to be relocated to the Sudetenland in late-1944, a lack of materials, and the Allied bombing campaign), the plans had to be changed and the order for production of 80 Ostwind was placed in late January 1945, with 30 in February, 40 in March and 10 in April. In February there were again changes to the production orders with 20 in February, 40 in March and 20 in April. Despite these plans for the production of 80 vehicles by March 1945, Stahlindustrie managed to complete only 7 vehicles. The total number of assembled Ostwinds by the Stahlindustrie was 22 vehicles. Because in late 1944, it was apparent that the Stahlindustrie could not reach the arranged Ostwind numbers, unknown numbers of turrets were also transported to Ostbau Sagan for assembly. The estimated production numbers of the Ostbau are 1 in December, 13 in January, 7 in February and 1 in March. Altogether, the production of the Ostwind (by both factories) is around 44 vehicles in addition to the prototype. This information is based on Panzer Tracts No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects development and production from 1942 to 1945. This low number should not be surprising if we take into account the chaotic state that Germany was in 1945.
When the actual Ostwind production began and how many were built is unclear. The production could have started in late-1944 or early-1945, with sources disagreeing. The exact number of produced vehicles is difficult to determine as the various authors give different numbers. Beside the prototype, the number of produced vehicles goes from as little as 6 to over 40. For most sources, including authors A. Ludeke (Waffentechnik im Zweiten Weltkrieg), D. Nešić (Naoružanje Drugog Svetsko Rata-Nemačka) and W. J. Spielberger (Gepard The History of German Anti-Aircraft tanks), the number of completed Ostwinds is believed to be 43 vehicles. According to P. Chamberlain (Encyclopedia of German Tanks of World War Two – Revised Edition) though, 36 were converted and 7 were new-build vehicles. H.L. Doyle (German Military Vehicles) gives a number of only 6 produced. D. Terlisten (Nuts and Bolts Vol.13 Flakpanzer, Wirbelwind and Ostwind) gives a number of 40 vehicles based on the information provided by Lt. Graf von Seherr-Thoss. In addition, he also notes that according to German Heereswaffenamt Wa I Rü document, 7 vehicles were built in March 1945. The number of 40 built vehicles is also noted by B. Perrett (Panzerkampfwagen IV Medium Tank 1936-1945).

Organization

All Flakpanzers based on the Panzer IV chassis were used to form special anti-aircraft tank platoons (Panzer Flak Zuge). These were used primarily to equip Panzer Divisions of the Heer and Waffen SS, and in some cases given to special units. By the end of March 1945, there were plans to create mixed platoons equipped with the Ostwinds and other Flakpanzers. Depending on the source, they were either to be used in combination with six Kugelblitz, six Ostwinds and four Wirbelwinds or with eight Ostwinds and three Sd. Kfz. 7/1 half-tracks. Due to the war’s end and the low number of Ostwinds built, this reorganization was never truly implemented.

In Combat

Only being completed in small numbers by the war’s end, the Ostwind’s operational combat use was limited. The prototype was, as mentioned earlier, used successfully during the Allied liberation of France. According to W. J. Spielberger, it was also used during the German Ardennes Offensive in late-1944. It managed to survive the defeat of the German Forces in France despite its turret being built only using mild steel. It was returned to Germany and its fate is not known.
By the time the first production Ostwinds were completed, the Allies and the Soviets were already rampaging through Germany. In the chaotic state that Germany was in, it is not clear how many or which units received Ostwind vehicles. There is an additional problem in the identification of which unit received Ostwinds due to the sources’ lack of distinction between Ostwinds and Möbelwagens.
One example that we know used Ostwinds was the 501st SS Heavy Panzer Battalion. This battalion had, by November 1944, lost all its anti-aircraft weapons and equipment. The surviving personnel of its anti-aircraft tank platoon (part of the 4th Kompanie) was moved from Wilhelmsdorf to Schwabhausen in Thuringia for resupply and training on the new Flakpanzers. By the end of December 1944, it was again moved to Bruggen, near Cologne, for further training.
While the 501st SS Heavy Panzer Battalion was engaged in the Ardennes Offensive, due to being in the process of reforming, its anti-aircraft platoon was not able to participate in this German offensive. This unit was first equipped with four Wirbelwinds followed by four Ostwinds. The commanders of these Ostwinds were SS Oberscharführers Kastelik, Deitrich and Rätzer. The last Ostwind was commanded by a Luftwaffe officer who was not part of this unit. For the anti-aircraft tank platoon HQ, only two Schwimmwagens were provided.

It is difficult to notice, but the production vehicles were provided with an additional armored bulge on the lower part of the turret’s front. This was meant to prevent the possible deflection of small caliber fire into the hull top. The large box on the hull side is for the spare 3.7 cm barrel. Source

The same abandoned Ostwind, possibly somewhere in Germany. Note the different positions of the main gun and the turret in contrast to the previous picture. Source
By February 1945, the training process was complete and this platoon would take part in the upcoming Operation Southwind (Unternemen Südwind). This was a planned German offensive operation against the Soviet bridgehead in the Nitra region of Hungary that lasted from 17th to 24th February 1945. While the 501st SS Heavy Panzer Battalion’s Tiger IIs were spearheading the attack, the Flakpanzers (Wirbelwinds and Ostwinds) followed up in a support role. They were, thanks to their speed and firepower, successfully able to engage and destroy enemy infantry, anti-tank and machine-gun positions while the Tiger tanks concentrated on enemy armor. With the capture of Kemend and Bina, the last Soviet resistance in this bridgehead was destroyed. Operation Southwind was one of the last successful German offensive actions on the Eastern Front. Only one Wirbelwind was lost during this operation.
The next occasion when the Ostwind would see action was the failed German offensive at Lake Balaton, Operation Spring Awakening (Unternehmen Frühlingserwachen), that lasted from 6th to 14th March 1945. The offensive began and, once again, the 501st SS Heavy Panzer Battalion was spearheaded by its Tiger and Panther tanks and supported by the Flakpanzers. It is interesting to note that the Flakpanzers’ commanders received orders not to engage enemy aircraft but to preserve ammunition for use against ground targets and in support of the Tigers only. The Flakpanzer commander Oberscharführer Kurt Fickert later wrote “…We drove in open formation behind the Tigers and Panthers to subdue enemy infantry. I was instructed by Peiper to support our infantry in house-to-house fighting. Several Panthers followed us to destroy any enemy tanks that might appear …. Peiper forbade us to engage enemy aircraft, our infantry was to defend themselves and we were to conserve our ammunition for the ground battle.”
During the Soviet offensive at Veszprem in March 1945, the Germans were forced to pull back their forces. On 20th March 1945, the Leibstandarte division’s position east of Inóta-Bakonykuti was attacked by the Soviet 4th Army and 6th Guards Tank Army. To support the withdrawal of the German units, four Flakpanzers (two Ostwinds and two Wirbelwinds) commanded by Oberscharführer Fickert were positioned on a nearby hill at Várpalota, from where they engaged the advancing Soviet units.
By April 1945, the 501st SS Heavy Panzer Battalion lost most of its armor and, without any hope for new replacements, the surviving crew members were gathered to form mixed infantry battle groups. This also included a number of surviving crew members from the anti-aircraft platoon and even their supporting repair workshop personnel. The final fate of the Ostwinds from that unit is not known, but they were all probably lost by the time of the German surrender in May 1945.
An interesting fact is that, on 15th March 1945, there were still around 159 operational Flakpanzers of all types. Most (97) were stationed on the Eastern Front, 41 in the West and 21 in Italy. In contrast to other Flakpanzers based on the Panzer IV chassis, no Ostwind vehicles survived the war.

Ostwind based on the Panzer III

As the new Flakpanzers were only provided to the Panzer divisions, the Sturmartillerie (Assault Artillery) units were left without a proper defense against the Allied air forces. In order to provide their own units with adequate anti-aircraft protection, the Assault Artillery Generals demanded a similar vehicle be designed. As the assault artillery units mostly used StuG IIIs and because of the lack of spare Panzer IV chassis, this meant that only the Panzer III was available for this modification. The whole development process was slow and, in early 1945, a delegation lead by Baurat Becker was sent to Ostbau-Sagan for evaluation of possible turret installations. Ostbau Sagan lacked production capabilities and was barely managing to keep up with Flakpanzer production. For this reason, Assault Artillery officials had decided that the production of the Flakpanzer III could be carried out in other factories.

The Ostwind and Wirbelwind turret was deemed sufficient for the job and in March 1945 an order for 90 turrets was placed. The Waffenamt reluctantly gave only 18 turrets. How many were completed is not known but according to new information around 11 were built and given to few Sturmgeschuetz Brigaden (Stu.G.Brig.).

Ostwind II

This was a proposed improvement of the original Ostwind, armed with two 3.7 cm Flak 43 guns mounted side by side in an enlarged turret and crewed with an additional loader. Some sources claim that one prototype was built by Ostbau-Sagan in January 1945 and sent to a training center at Ohrdruf.

Conclusion

The Ostwind was the German solution to the need for an effective Flakpanzer. It had strong firepower, relatively good protection, was easy and simple to build, its tracked Panzer IV chassis gave it the mobility to keep up with the Tigers and Panthers and, most importantly, it could immediately engage enemy aircraft. The greatest downside was that it was built too late into the war and in too small numbers (less than 50) to even have a theoretical chance of influencing the outcome of the war.

Specifications
Dimensions	5.92 x 2.9 x 2.9 meters
Total weight, battle-ready	22 tonnes
Crew	5-6 (1-2 gunners, commander, loader, driver and radio operator).
Armament	3.7 cm Flak 43 Elevation: -10 – +90 Degrees
Hull Armor	Front 80 mm, side 30-20 mm, top and bottom 10 mm and rear 10-20 mm
Turret Armor	16 mm all-around – later increased to 25 mm
Propulsion	Maybach HL 120 TRM
Suspension	Leaf springs
Speed on road	38 km/h (24 mph)
Range (road/off road)	200 km (120 miles), 130 km (80 miles)
Total production	6-45

Source

D. Nešić, (2008), Naoružanje Drugog Svetsko Rata-Nemačka, Beograd
P. Chamberlain and H. Doyle (1978) Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
Walter J. Spielberger (1982). Gepard The History of German Anti-Aircraft tanks, Bernard & Graefe
Walter J. Spielberger (1993). Panzer IV and its Variants, Schiffer Publishing Ltd.
T. L.Jentz and H.L. Doyle (2002) Panzer Tracts No.20-2 Paper Panzers, Panzer Tract
P. Chamberlain and T.J. Gander (2005) Enzyklopadie Deutscher waffen 1939-1945 Handwaffen, Artilleries, Beutewaffen, Sonderwaffen, Motor buch Verlag.
W. Oswald (2004). Kraftfahrzeuge und Panzer, der Reichswehr, Wehrmacht und Bundeswehr ab 1900, Motorbuch Verlag,
P. Agte (2006) Michael Wittmann and the Waffen SS Tiger Commanders of the Leibstandarte in WWII, Stackpole Books
D. Doyle (2005). German military Vehicles, Krause Publications.
B. Perrett (2008) Panzerkampfwagen IV Medium Tank 1936-1945, Osprey Publishing.
D. Terlisten (1999). Nuts and Bolts Vol.13 Flakpanzer, Wirbelwind and Ostwind,
Ian V.Hogg (1975). German Artillery of World War Two, Purnell Book Services Ltd.
T. L.Jentz (1998). Panzer Tracts No.12 Flak selbstfahrlafetten and Flakpanzer
T. L.Jentz (2010). Panzer Tracts No. 12-1 – Flakpanzerkampfwagen IV and other Flakpanzer projects development and production from 1942 to 1945.
A. Lüdeke (2007) Waffentechnik im Zweiten Weltkrieg, Parragon books.

German Reich (1944)
Self-Propelled Anti-Aircraft Gun – 87-150 Built

As the German Luftwaffe (German Air Force) lost control over the skies of Germany in the second half of the Second World War, it could no longer provide sufficient protection against Allied aircraft. Panzer divisions were especially affected by the lack of cover from fighter aircraft because they were always at the center of the most intense fighting.

The Germans already had copious amounts of half-tracked Self-Propelled Anti-Aircraft Guns of different calibres and weights (Sd.Kfz.10/4, Sd.Kfz.6/2, Sd.Kfz.7/1, etc). As these vehicles had very limited or no armor, they were vulnerable to enemy fire either from ground or air. The crew needed better protection from small arms fire and artillery/mortar high explosive fragmentation shell shrapnel. A tank-based anti-aircraft vehicle (German: Flakpanzer) could solve this problem, as it would have thick enough armor to resist most ground attack with the exception of larger caliber guns. They would also provide some protection against air attacks, but even tanks could be destroyed by air ground-attack fire. An open-topped Flakpanzer’s best defense against air threats was its anti-aircraft gun.
The first attempt was the Flakpanzer I, which was built only in limited numbers and was more an improvisation of an existing design rather than a purpose-built vehicle. The German abbreviation Flak is short for Fliegerabwehrkanone (Anti-aircraft gun: Flieger aircraft – literally, flyer + Abwehr defense + Kanone gun, cannon).
The later 20 mm armed Flakpanzer 38(t) had weak firepower and insufficient armor protection. It was more of a temporary solution. The later built Möbelwagen (based on a Panzer IV tank chassis) was armed with the much stronger 3.7 cm Flak 43 anti-aircraft gun, solved the problem with the weak main weapon but it was not without defects. The Möbelwagen needed too much time to set up for firing and thus was ineffective in a sudden enemy attack. A Flakpanzer that could respond without preparation was more desirable, and that solution would be the Flakpanzer IV 2 cm Flakvierling 38 mostly known under the name ‘Wirbelwind’, meaning ‘Whirlwind’ in English.

The Flakpanzer IV (2 cm Flakvierling 38) ‘Wirbelwind’. Photo: Public Domain

Beginnings of a New Flakpanzer

In late 1943, the need for a Flakpanzer was dire. The decision was made by the German Heer (German field army) to reuse chassis of already operational service tanks. The Panzer I and II were outdated or used for other purposes. The Panzer III tank chassis was used for the production of the StuG III and thus not available. The Panzer IV and the Panzer V Panther were considered next. The Panzer IV tank chassis was already in use for several German modifications, so it was decided to use it for the Flakpanzer program. The Panzer V Panther was for a short time considered to be used as a Flakpanzer armed with two 37 mm anti-aircraft guns, but mostly due to high demand for tank hulls, the project never went beyond a wooden mock-up.
The first Flakpanzer based on the Panzer IV tank chassis was the 2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV. Only one prototype was built. It did not receive any production orders but the prototype was modified and upgraded with the larger 3.7 cm Flak 43 (known under the name Möbelwagen by its crews) and around 240 of this version were produced. The Möbelwagen had sufficient firepower to destroy enemy planes and the crew was protected by armored plates on four sides, which needed to be dropped down to use the gun effectively. The Möbelwagen needed time to set up for action and was therefore not a success.
In early 1944, Generaloberst Guderian, Generalinspekteur der Panzertruppen (Inspector-General for Armored Troops), gave the In 6 (Inspektion der Panzertruppen 6/ Armored Troops inspection office 6) direct orders to begin work on a new Flakpanzer. The main requirements for such a vehicle were:

• The turret should be fully traversable (360°)
• The new turret should have three or four crew members
• The crew operating the anti-aircraft gun should be well protected and it should be open-top as to give the crew a better view of the skies and because of the smoke produced by the four guns
• The turret traverse mechanism should be simple
• The main weapons (it had to have at least two guns) should have a minimum effective range of 2000 m, with enough ammunition
• The height must be lower than 3 m
• Radio equipment was important

The Karl Wilhelm Krause Flakpanzer

At the same time as the design and developing of the Wirbelwind was just beginning, a battlefield modification of a Panzer IV tank chassis was carried out involving the use of a 2 cm Flak 38 Flakvierling, with the intention of building a Flakpanzer. In early 1944, Untersturmführer Karl Wilhelm Krause (commander of the Flakabteilung of the 12th SS Panzer Regiment part of the ‘Hitlerjugend’ Division) made plans for an experimental Flakpanzer. He gave orders to his men to mount a 2 cm Flak 38 Flakvierling on a Panzer IV tank chassis (its turret may have been damaged). The tank turret was removed and, in its place, a 2 cm Flak 38 Flakvierling was installed. The original gun shield was removed, but later built vehicles had a newly modified three-sided gun shield (but much simpler construction than the Wirbelwind). Unknown numbers were built, but possibly up to three vehicles. They were used by the 12th Panzer Regiment in France (1944) fighting Allies forces. These vehicles managed to shoot down 27 Allied aircraft’s. This project was carried out without knowledge of the design team working on the plans for the new Flakpanzer (ordered by Guderian) but it would have a great influence on it.

This is the first Karl Wilhelm battlefield modification Flakpanzer based on a Panzer IV chassis and armed with 2 cm Flak 38 Flakvierling anti-aircraft gun. Note the Flak gun shield is missing and thus we know that it was the first Karl Wilhelm ‘prototype’. Photo: Operation Dauntless

This is the second Karl Wilhelm Flakpanzer. It has a simple three sided gun shield. Unknown Source

Future Development

In 6’s new Flakpanzer project was led by the Generalmajor Dipl. Ing. E. Bolbrinker. After a short analysis of the state of the German military economy, it became immediately clear that designing a completely new Flakpanzer was out of the question. The German industry was hard pressed mostly due to the high demands for more combat vehicles and constant Allied bombing raids so the possibility of designing and a building a new vehicle would take too much time and resources (both were lacking by 1944). Another solution was needed. Generalmajor Bolbrinker hoped that, by collecting a team of young tank officers, their enthusiasm and ideas would help him find a solution to this problem.
This group of young tank officers was lead by Oberleutnant J. von Glatter Gotz (most known for his Kugelblitz Flakpanzer design). Oberleutnant Gotz somehow heard of Untersturmführer Krause’s Flakpanzer work and dispatched Leutnant Hans Christoph to France in order to inspect this vehicle. Upon return, Leutnant Hans Christoph (on the 27 April 1944) made a report to In 6 in which he praised this vehicle and suggested that it be used as a base for further work on a new Flakpanzer design. This report had a major impact in making a final decision to produce the first prototype. By agreement between Generaloberst Guderian and Waffen Prüfen 6 (Wa Prüf 6 – design office for armored vehicles and other military equipment), the first prototype was to be built by a Panzer IV repair workshop named Krupp-Druckenmuller GmbH from Berlin-Mariedorf. By the end of May 1944, the prototype was ready and it was presented to Generaloberst Guderian, officers from Waffen Prüfen 6 and In 6 in the German research center Kummersdorf. Beside the Wirbelwind Flakpanzer, another project was also presented: the Alkett Flakpanzer IV armed with 3.7 cm Flak 43. Guderian was very impressed by the new Wirbelwind Flakpanzer and asked for it to be put in production.
It was sent (together with Ostwind prototype) to Bad Kuhlungsborn on the Baltic Coast for live firing tests of the guns. These tests were held in July of 1944, and around 3,000 rounds of ammunition were fired against air and ground targets without any problem to the gun or the vehicle itself. Observers from In 6 reported positive results for this vehicle and that the whole construction was feasible and without problems.

The Name

There are several names given to this vehicle: 2 cm Flakvierling 38 auf Sfl PzKpfw IV, Flakpanzerkampfwagen IV (Sd.Kfz.161/4), Flakpanzer IV (2 cm) auf Fahrgestell IV/3 or simply Flakpanzer IV/2 cm Flakvierling 38.
The German word ‘Vierling’ is best described as quadruplet, and the Flakvierling is an anti-aircraft weapon with four guns. The abbreviation Sfl is short for ‘Selbstfahrlafette’ – self-propelled carriage. The German word ‘Fahrgestell’ means chassis. The ‘Flakpanzerkampfwagen’ translates to anti-aircraft armored combat vehicle or anti-aircraft tank. The Wirbelwind name is very common in many sources. The origin or even if it was an original German designation is not clear as none of the sources give a specific explanation of the origin of this name. Thanks to some combat reports like the one from the s.Pz.Abt.503 (source Panzer Tracts No.12), we have information that there are individual crews who simply called these vehicles ‘Vierling’ (due to its four guns).
This article will use Wirbelwind name mostly due simplicity but also because large numbers of different authors use it.

Construction

As already mentioned, the Wirbelwind was built by using the refurbished Panzer IV (mostly Ausf.G or H, possibly even small numbers of Ausf.J) tank chassis. The suspension and running gear were the same as those of the original Panzer IV, with no changes to its construction. It consisted of eight pairs of small road wheels (on each side) suspended by leaf-spring units. There were two front drive sprockets, two rear idlers and eight return rollers in total (four on each side).
The engine was the Maybach HL 120 TRM 265 hp @2600 rpm, but according to Panzer Tracts No.12 the engine was modified so that it put out 272 hp @2800 rpm. The design of the engine compartment was unchanged. Maximum speed was 38 km/h with an operational range of 200 km.
Most parts of the upper tank hull were unchanged from the original Panzer IV. The driver’s front observation hatch and the ball-mounted hull machine gun remained. As the Wirbelwind was constructed by using rebuilt Panzer IV chassis of different versions, there were some minor detail differences. For example, some vehicles had two vision ports (one on each side) while some did no. Some had Zimmerit (anti-magnetic mine paste) on the hulls, the fuel hand pump and the starter (for the inertia started) were moved near the driver seat on some versions.
The armor thickness also varies from model to model. The maximum armor thickness of the lower frontal glacis varied from 50 to 80 mm thick, the sides were 30 mm, the rear 20 mm and the bottom armor was only 10 mm. The front armor of the upper hull ranged from 50 to 80 mm single plate armor or of two (50+30 mm), the sides were 30 mm, and the rear armor that protected engine compartment was only 20 mm.
The 2 cm Flak 38 Flakvierling anti-aircraft quad gun was placed in a nine-sided, open-topped turret. Each of these nine-sided plates were built by welding two angled armored plates. The lower plates were angled outside and the upper one was angled towards the inside. The armor of these plates was 16 mm thick. The angled armor provided some extra protection but in general, it could only protect the crew from small caliber weapons or grenade splinters. The top was completely open and this was done for a few reasons: to speed up production, to allow the crew a better view of their surroundings and help in target acquisition and threat evaluation, and to help expel the choking gases that were released when the four guns were fired. There were plans to add extra armor plates at the top for better protection but this was never done. The upper front armor plate (between the 2 cm Flak barrels) had a small hatch that could be opened to allow the gunner to see and engage ground targets. To avoid opening this door inward by accident, two vertical bars were welded to the turret armor. There were original plans to add two side hatch doors on the fighting compartment (on both sides) but as it would cause future delays in production this idea was never implemented. Also, the top was planned to be protected by an opening wire grid (similar to Sd.Kfz.222 armored cars) for protection from grenades, but this was also never implemented.
The 2 cm Flak 38 Flakvierling had to be adapted in order to fit in this turret. First, there were no seats for the crews, as there were removed from the gun. Seats were instead placed on the turret interior walls, with one on each side plus one behind the gun. The gun shield was also removed. To make a stable platform for the new gun, it was necessary to add a new gun mount which was constructed from two T shaped carriers (around 2.2 m long) that were welded to the chassis interior. An additional plate (with 0.8 cm x 0.8 cm x 1 cm dimensions) with holes for securing the gun was also added. This plate also had a large round shaped opening for the mounting of the collector ring. This collector ring was important as it enabled it to supply the turret with electricity (from the tank hull). There was also a locking mechanism designed to lock down the Flak gun (and thus the whole turret) in place during driving. Some extra room had to be made for equipment needed for the main weapons, for example, the cleaning box. A box with spare barrels was placed on each side of the engine compartment.
In order to make the construction of this vehicle easier, no extra traverse mechanism was provided. The turret was instead traversed by using the main gun traverse. The new turret was in essence just an extended gun shield. The only real connection that the Flak gun had with the turret were three metal lugs under the crew seats. The ring-shaped turret base was welded to the hull top. To help with the rotation, ball bearings were added into this base which made turret movement much easier. The maximum traverse speed was around 27° to 28° (depending on the source) per second. The German Aviation Experimental Facility (Deutsche Versuchsanstalt für Luftfahrt – DVL) built and tested a prototype hydraulic traverse mechanism which increases the speed to 60° per second, but it was never installed in any Wirbelwind vehicle.
The elevation of the 2 cm Flak 38 Flakvierling was from –10° to +90° (with other sources specifying -10° to +100°). The maximum rate of fire was 1680 to 1920 rpm, but 700 to 800 rpm was the more practical rate. The gunner fired the Flak guns by using two-foot pedals, each pedal being responsible for a diagonal of the four-barrel arrangement (so upper left with lower right, for example). It was recommended that the gunner fire only two guns at a time, but this was largely ignored, depending on the combat situation or availability of ammunition. The 2 cm Flak 38 Flakvierling usually had a deflector box but due to the limited space, its installation was not possible. In order to avoid contact between the hot used cartridges and stored ammunition, some kind of case or mesh bags were possibly used. This gun had an effective range of around 2 km, enough to engage low flying attack planes. In total, some 3,200 rounds of ammunition were carried by the vehicle. At the lower rear part of the turret, on both sides, were ammo racks each with eight magazines. The remaining ammunition was stored below the gun. The secondary weapons consisted of the standard hull ball-mounted 7.92 mm MG34 machine gun with around 1,350 ammunition rounds. The crew would also use their personal weapons, mostly 9 mm MP38/40 submachine guns.
The five-man crew consisted of the commander/gunner, two loaders, a driver and a radio operator. The positions of the radio operator (Fu 2 and Fu 5 radios were used), who also operated the hull mounted MG 34 machine gun, and the driver were the same as on the original Panzer IV. The remaining three crew members were positioned in the new turret. The commander/gunner was position in the middle, behind the main guns, whilst the loaders were placed on the left and right side in front of him. For crew communication, an interphone was provided which was located behind the right loader. As the open-topped turret exposed the crew to the elements, a canvas was provided for protection. The Wirbelwind dimensions were: length 5.92 m, width 2.9 m and a height of 2.76 m. Total combat weight was around 22 metric tonnes.

A newly rebuilt Wirbelwind at Ostbau Sagan. For this vehicle, the Ausf.G tank chassis was reused. We can easily identify it as the Ausf.G by the single 50 mm front armor plate. Photo: SOURCE

Production and Numbers Built

When the Wirbelwind demonstration was completed, Generaloberst Guderian was informed that some 20 Wirbelwinds could be produced by July 1944. On the 8th June 1944, the Ostbau-Sagan (from Segan in Schlesien) was charged with the production of the Wirbelwind Flakpanzer. The men in charge of the whole project were Lt. Graf von Seherr-Thoss. The workers under his command (80 in total) were mostly recruited from Panzer-Ersatz und Ausbildungs-Abteilung 15. It is interesting to note that the Wirbelwind was produced by the German army itself without the inclusion of any commercial firms.
Due to a shortage of new tank chassis, the Ostbau-Sagan workers would instead reuse refurbished (damaged returned from the front) Panzer IV tank chassis. As Ostbau-Sagan was only a small repair workshop, it lacked the production capacity and thus other manufacturers had to be included in this project. The Ostmark-werke (Wienna) was tasked with the 2 cm Flakvierling modification and the turrets were provided and built by the Deutsche Rohrenwerke. Ostbau-Sagan had in essence only one task, to assemble the vehicles when all the parts were delivered. Despite the promise that 20 vehicles would be ready by the end of July 1944, only 17 were completed by that time.
The first production order for 80 vehicles was extended to 130 by September 1944. The production could never meet these numbers. By December 1944, around 100 Wirbelwinds had been constructed and, at the same time, a new order for a further 100 vehicles was issued. In January 1945, due to the rapid Allied advance, the equipment and workers of the Ostbau-Sagan had to be relocated to Teplitz-Schonau (in the Protectorate of Bohemia and Moravia, current day Czech Republic) and this caused a delay in production. Vehicle construction recommenced in February 1945 and by March, five more vehicles were produced including a few additional turrets before the production was stopped due to the end of the war.
As with most German late war built vehicles, the total number of produced Wirbelwinds is hard to establish. Most authors (like David Doyle and Detlev Terlisten) give a number of 122 constructed vehicles. Bryan Perrett (New Vanguard) states that a total of 140 Wirbelwinds were built. Authors Peter Chamberlain and Hilary Doyle give a number of 86 (plus the prototype). Author Heinz J. Nowarra gives a number of 150 vehicles. Walter J. Spielberger gives a number of 105 with the monthly production in August 1944 of 22, September 30, October 10, November 30, December 8, January (1945) 3 and February 2. Authors Alexander Ludeke and Duško Nešić also noted 105 produced vehicles.
Due to the late stage of the war, the chaotic state in Germany and the loss of many archive documents, the exact number of constructed vehicles is not confirmable with 100% accuracy.

Illustration of the Flakpanzer IV (2 cm Flakvierling 38) ‘Wirbelwind’, produced by Tank Enyclopedia’s own David Bocquelet.

The 2 cm Flak 38 Flakvierling

The 2 cm Flak 38 proved to be a successful weapon during the war, especially the four-barrel Flakvierling versions. It was designed to shoot down low-flying aircraft but it was also found to be very effective when used against unarmored ground targets.
The Flak 38 Flakvierling was designed by Mauser-Werke to replace the old Flak 20, and was introduced in May 1940. At first, it was mostly used by the German Kriegsmarine (navy) to provide anti-air defence for battleships, destroyers and cruisers. During the war, this anti-air gun saw much wider use with the rest of the German army in various mounts. This gun was transported on the Sonderanhanger 52 platform and carriage which was the same as for the one gun Flak 38 original version but enlarged and strengthened. The Flak 38 Flakvierling was also used as a mobile mounted weapon on several German vehicles, like half-tracks (Sk.Kfz 7/1), tanks, trucks, and even on armored trains. An interesting fact is that, on some later versions, radars were fitted, in which case a parabolic reflector was installed between the four gun barrels. During WWII, the Flak 38 Flakvierling proved to be a highly effective and successful weapon that remained in use throughout the war, with some 3850 being produced.
The Flak 38 Flakvierling had 8 crew members. Its effective range was 2 km (6562 ft) or 2.2 km (7229 ft), depending on the source, with the maximum horizontal range of 5780 m (5230 yds). The maximum rate of fire was 1680 to 1920 rpm, (700-800 rpm was a more appropriate operational rate of fire). The gun could traverse a full 360° and the elevation was –10° to +100°. The weight in action was some 1520 kg (3352 lbs). The Flak 38 Flakvierling was first equipped with the Flakvisier 40, that was a modified version of the Flakvisier 38. But, during the later part of the war, this was replaced by more simple types.
For this gun there were several different types of ammunition available that were used in combat, some of them were:

• SprGr.Patr.L/Spur – HE (high explosive) shell with self-destroying tracer (velocity 900 mps/2950 fps)
• 2 cm Pzgr Patr 40 L/Spur – AP (armor piercing) shell with a tungsten core, armor penetration at 100 m was 40 mm (1.57 in at 110 yds), probably rarely used because of a shortage of tungsten.
• 2 cm Pzgr Patr L/pur m Zerlegung – AP/HE/incendiary shell with no fuse and with a heat relay self-destroying tracer. Velocity was 830 mps/2720 fps
• 2 cm Sprgr Patr L/Spur (Ub) – Empty practice shell.

The Flak 38 Flakvierling had 8 crew members. This one has no shield armor. Photo: Bundesarchiv

Organization

All Flakpanzers based on the Panzer IV chassis were used to form special anti-aircraft tank platoons (Panzer Flak Zuge). These were used to equip primary Panzer Divisions of the Heer and Waffen SS, and in some cases given to special units. At first, these Panzer Flak Zuge were equipped with eight Möbelwagens. By the time the first Wirbelwinds were ready to be sent to the front, the Panzer Flak Zuge organization was changed to include four Wirbelwinds and four Möbelwagens. In February 1945, the Panzer Flak Zuge were divided into three groups (Ausfuhrung A, B, and C). The Panzer Flak Zuge Ausf.A was the standard unit which included four Wirbelwinds and four Möbelwagens. The Ausf.B was equipped with eight Wirbelwinds and the Ausf.C with eight Möbelwagens. By April 1945, this organization was changed to eight Ostwinds (similar to Wirbelwind but armed with 37 mm gun) and three Sd. Kfz. 7/1 half-tracks. Due to the war end and a low number of build Ostwinds, this reorganization was never truly implemented.

Front view of the Wirbelwind, this vehicle has bolted 30 mm armor on the front plate. Photo: SOURCE

In Combat

During the war, a number of Panzer Flak Zuge with Wirbelwinds would be formed and used to equipped many German Panzer units which served on the Eastern or Western fronts until the end of the war. The units were equipped with a Zug of four (unless otherwise stated) Wirbelwinds were: 3rd Panzer Regiment (2nd Panzer Division) Western Front, 33rd Panzer Regiment (2nd Panzer Division) Western Front, 15th Panzer Regiment (11th Panzer Division) Western Front, II. Abteilung/Panzer-Regiment 39 (17th Panzer Division) had three – Eastern Front, StrumPz.Kpfw.Abteilung 217 had two – Western Front, Panzerjäger Abteilung 519 Western Front, Panzerjäger Abteilung 559 Western Front, Panzerjäger Abteilung 560 Western Front (Ardennes) later Eastern Front (Hungary), Panzerjäger Abteilung 653 Eastern Front, Panzerjäger Abteilung 654 had four (plus three replacements vehicles) Western Front, Panzerjäger Abteilung 655 Western Front (two companies) and possibly one company in Hungary, s.Pz.Abteilung 503 Eastern Front, s.Pz.Abteilung 506 Western Front, s.Pz.Abteilung 509 Eastern Front, 1st SS-Panzer Regiment from the 1st SS Panzer Division “Leibstandarte Adolf Hitler” Western front and from the January 1945 reposition to the Eastern front, 2nd SS-Panzer Regiment of the SS Panzer Division “Das Reich” (same as Leibstandarte Adolf Hitler), 12th SS Panzer Regiment 12th SS Panzer Division “Hitlerjugend” had four plus possibly up to three modified Panzer IV as Flakpanzers Western front until December 1944 when it was sent to the Eastern Front, SS Pz.Kpfw. Abteilung 17 from the 17th SS Panzergrenadier Division “Gotz von Berlichingen” Western front, s. SS Pz.Abteilung 501 Western front and from February 1945 Eastern front and the last was s. SS Pz.Abteilung 503 Eastern front.

An Ausf.H-based Wirbelwind captured by the Allies somewhere in France 1944. Photo: SOURCE
There is also a possibility that smaller numbers were given to other units. Around 18 Wirbelwinds were given to the Panzer-Ersatz-Abteilungen, a rear unit in charge of training and replacement. Despite the small numbers constructed, they saw heavy action on both fronts.
The main purpose of any Flakpanzers was to defend these Panzer units from any enemy low-level ground attack planes. The Flakpanzers would engage enemy planes that had entered their weapons range (for the Wirbelwind that was around 2 km). They would either try to bring it down or to force them to abandon the attack and find another easier target. The best way to bring a plane down was to shoot in front of its flying path. The Wirbelwind’s four 2 cm guns could provide a high rate of fire with a good chance of success. The Wirbelwind was, because of this, often attacked by enemy planes in order to destroy them and leave the remaining German forces without adequate protection. The four 2 cm guns were also, from time to time, used for attacking ground targets. While useless against tanks, it had a destructive effect on any soft armored vehicles and infantry.
The Wirbelwind proved to be an effective anti-aircraft vehicle. This can be seen in the report of the s.Pz.Abt.503:

‘… the Vierling (Wirbelwind) have proven especially useful. Through their armor and mobility, they are always immediately capable of providing adequate air defense and they are also outstandingly effective in ground combat. In a short period, the Vierling section scored three confirmed and two probable aircraft kills.’

– Panzer Tracks No.12.

Despite being an effective anti-aircraft vehicle, the Wirbelwinds were often attacked by the enemy ground attack planes. Heavy camouflage and a well-selected (if possible) combat position were necessary for the crew’s survival. This Wirbelwind was constructed by using the older Panzer IV Ausf G. chassis. Photo: WW2 in Color

This Wirbelwind was hit by an ISU-122 (according to D. Terlisten) during the battle at Lake Balaton in 1945. The number 91 and the white markings (at the impact zone) were added by the Soviet examining teams. Photo: SOURCE

This Wirbelwind received two front hits. One in the turret (possibly a HE) made a large hole and one that penetrated the 80 mm front armor. Photo: SOURCE

Surviving Vehicles

Today, only two Wirbelwinds are known to have survived the war, one in Canada and one in Germany. The one in Canada is located at Base Borden military museum, the exact history of which is not known.
The second Wirbelwind still in existence possibly belonged to the 1st SS Panzer Division. It saw some action during the Battle for the Bulge. It was damaged by an Allied ground attack plane in December of 1944 near the rail station of Buchholz (Belgium). Before it was taken out of action during this engagement it managed to shoot down one enemy plane. It was abandoned by the Germans and in late January 1945 it was captured by the advancing American forces. It was shipped to America after the war for further testing at the Aberdeen Proving Ground. In 1967, it was given back to Germany and, after restoration in late 90’s, was given to the Heeres-flugabwehrschule Rendsburg.

The surviving Wirbelwind located at Base Borden military museum. Photo: Wikimedia Commons

The Wirbelwind at Heeres-flugabwehrschule Rendsburg, next to it is the remaining Kugelblitz turret. Photo: pro-tank.ru

The Wirbelwind II “ Zerstorer 45”

In the hope of increasing the Wirbelwind’s firepower, in December of 1944, Ostbau built one prototype armed with quadruple 3 cm Flakvierling 103/28. Due to the chaotic situation in the German war industry, only this single prototype was ever built. According to Walter J. Spielberg, up to five were built by January of 1945 and these were issued to front line troops for use.

Conclusion

The Wirbelwind proved to be an effective weapon during the war. It was relatively easy to construct, had good protection (compared to other Flak vehicles in use by the Germans), could shoot a large number of rounds in a short amount of time and, most importantly, it could immediately engage enemy forces either on the ground or in the air. The Wirbelwind fulfilled all requirements set by In 6.
The only negative side is that it was produced in low numbers by the end of the war. The low number of produced Wirbelwinds did not and could not have influenced the flow of the war against Germany. The main weapon calibre was, by 1944 standards, too weak and lacking in range but this did not prevent the Wirbelwind crews shooting down a number of Allied planes during the war.

Specifications
Dimensions	5.92 x 2.9 x 2.7 meters (19′ 5” x 9′ 6” x 8′ 10”)
Total weight, battle ready	22 tonnes
Crew	5 (Commander/gunner, two loader, driver and radio operator)
Armament	2 cm Flak 38 Flakvierling. Elevation: -10° to +90°
Armor	Turret: 16mm Hull: front 50 to 80 mm, sides 30 mm, rear 20 mm and the bottom 10 mm Superstructure: front 50 to 80 mm, sides 30 mm, rear 20 mm and the bottom 10 mm
Propulsion	HL Maybach 272 hp (200 kW)
Suspension	Leaf springs
Speed on /off road	38 km/h (24 mph), 20-25 km/h (12 – 16 mph) (cross country)
Range (road/off road)	470 liters, 200 km (120 miles), 130 km (80 miles)(cross country)
Total production	240

Sources

Heinz J. Nowarra (1968). German tanks 1914-1968, Arco Publishing company
Walter J. Spielberger (1993). Panzer IV and its Variants, Schiffer Publishing Ltd.
Walter J. Spielberger (1982). Gepard The History of German Anti-Aircraft tanks, Bernard & Graefe
Duško Nešić (2008). Naoružanje drugog svetsko rata-Nemačka , Tampopring S.C.G.
Thomas L. Jentz (1998). Panzer Tracts No.12 book Flak selbstfahrlafetten and Flakpanzer
Detlev Terlisten (1999). Nuts and Bolts Vol.13 Flakpanzer , Wirbelwind and Ostwind,
Alexander Ludeke (2007). Waffentechnik im Zweiten Weltkrieg, Parragon books.
Werner Oswald (2004). Kraftfahrzeuge und Panzer, der Reichswehr, Wehrmacht und Bundeswehr ab 1900, Motorbuch Verlag,
Ian V.Hogg (1975). German Artillery of World War Two, Purnell Book Services Ltd.
Peter Chamberlain and Hilary Doyle (1978). Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
David Doyle (2005). German military Vehicles, Krause Publications.

German Reich (1944-1945)
Self-Propelled Anti-Aircraft Gun – 240 Built

As the German Luftwaffe (German air force) lost control over the skies over Germany in the second half of the Second World War, it could no longer provide sufficient protection against Allied and Soviet aircraft. Panzer divisions were especially affected by the lack of the air fighter cover because they were always at the center of the most intense fighting. While the Germans already had copious amounts of half-tracked SPAAGs of different calibers and weights, these had the significant flaw of being themselves vulnerable to the planes they were meant to hunt. A tank based anti-aircraft vehicle could solve this problem, as it already had the armor to resist most aircraft armament, but little effort was done in this direction. The Flakpanzer I and the Flakpanzer 38(t) were built in some numbers but were considered unsuccessful, mostly due to the weak firepower of the 2cm Flak 38 by this late stage of the war.

2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV prototype. This vehicle was not accepted for production, but it was used as a basis for the later Möbelwagen. Source: Panzernet

Proposed Projects

In late 1942, at the request of German military officials, Krupp began working and designing the leichte Flak auf gepanzerter Sfl. (light anti-aircraft gun on a tank chassis). One of the first proposals was to use the chassis of the Panzer II Ausf.L ‘Luchs’ reconnaissance tank and arm it with a small caliber anti-aircraft gun (2 cm or 3.7 cm). The new experimental VK16.02 ‘Leopard’ was also considered for this purpose. In the end, partly due to the cancellation of the VK16.02 program, a new solution had to be found.
In February 1943, Krupp engineers started work on designing a new vehicle that would be used for this purpose. The result was a modified and shortened chassis of the Panzerkampfwagen IV medium tank with an open-topped weapon platform. This platform was box-shaped with folding double-walled sides and the main gun in the middle. The chassis only had six road wheels (rather than eight used on Panzer IV) with only three return rollers. Several different weapons were proposed for this vehicle: 2cm Flakvierling, 3.7 cm Flak 36 or 43 and possibly even the powerful but mechanically unreliable 5 cm Flak 41. This project was also abandoned, but parts of its design would be used on the next project.

Front view of the Möbelwagen, with part of the Flak 43 gun shield cut down. The lack of the machine ball mount in the hull can also be observed. Source: Panzernet
In late May and early June, because of urgency and a great need for such a vehicle, Krupp was rushed by the army to build the new Flakpanzer as soon as possible. In order to take advantage of already existing production capacities and thus accelerate the whole process, it was decided to use the Panzer IV tank chassis for this purpose.

2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV Prototype

The 2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV prototype was ready by September 1943. This vehicle was built using a Panzer IV tank chassis and by removing the tank turret and replacing it with a box-shaped (open top) superstructure armed with a 2 cm Flakvierling AA mount.
The 2 cm Flakvierling auf Fahrgestell Panzerkampfwagen IV prototype was sent to Kummersdorf and presented to a military inspection which was led by General Guderian. Guderian was satisfied with this prototype and placed an order for a serial production to start by the April 1944 with some 20 vehicles to be built per month.
None were built as Hitler (or even by Guderian depending on the source) preferred the larger and more powerful 3.7 cm Flak 43 anti-air gun. The single build prototype would be later used as a base for the improved ‘Möbelwagen’.

Flakpanzerkampfwagen IV (3.7 cm Flak 43) ‘Möbelwagen’

Since the 2cm Flakvierling Panzer IV project was rejected, Krupp was asked to design and build the proposed Flakpanzer IV armed with a 3.7 cm Flak. To speed up the whole process, Krupp workers and engineers simply reused the previous prototype. They did some minor modifications on it and installed the bigger 3.7 cm Flak 43 anti-aircraft weapon. Using the modified Panzer IV chassis (with six road wheels) was also considered but this proposal was not adopted.

Fresh built Möbelwagens ready to be sent to the front. Source:panzernet
This prototype was ready by the beginning of 1944 and was presented to the German Army for inspection. There were no major objections to this vehicle, which met almost all requirements. It has to be emphasized that this vehicle was considered a temporary solution until new and better anti-aircraft tanks were designed and built in sufficient numbers. The order for production was given in February 1944. The production was planned to begin in April 1944 with some 20 vehicles per month. In total, some 100 vehicles were expected to be completed by the end of 1944. Due to the slow production of the new ‘Wirbelwind’ and ‘Ostwind’ Flakpanzers, a new order was given for some 140 more vehicles to be built.
The official name of this vehicle was Flakpanzerkampfwagen IV. The ‘Möbelwagen’ nickname was given by the crews because of the similarities with a moving van (when the armored sides were raised for transportation). Although this is not its official name, this article will use this name for the sake of simplicity.

Like any other vehicle, it was necessary for crews to learn how to operate it efficiently. Source:panzernet

Technical Characteristics

The Möbelwagen, as already mentioned earlier, was built using the Panzer IV Ausf.H (later J) tank chassis. The Möbelwagens suspension and running gear were the same as those of the original Panzer IV, with no changes to its construction. It consisted of eight small road wheels (on both sides) suspended in pairs by leaf-spring units. There were two front drive sprockets, two rear idlers and eight return rollers in total. The engine was the Maybach HL 120 TRM, but modified so that it put out 272 [email protected] rpm instead of the usual 265 [email protected] rpm. The maximum armor thickness of the lower frontal glacis was 80 mm thick, the sides were 30 mm, the rear 20 mm and the bottom armor was only 10 mm. The design of the engine compartment was unchanged.
The upper tank hull was different from the original one used on the Panzer IV. It had a rectangular shape with vertical sides, somewhat larger but easier for production. The ball-mounted hull machine gun was removed. The front driver observation hatch remained unchanged. The front armor of the upper hull was 50 mm, the side were 30 mm, and the rear armor that protected engine compartment was only 20 mm. On top of the tank hull, beside the main weapon, four hatch doors were built-in. Two front hatch doors were used by the driver and the radio operator (Fu 2 and Fu 5 radios were used) to enter their positions. The two rear doors led to the ammunition rack’ where 400-416 rounds were stored.

Abandoned on the battlefield, possibly somewhere in Normandy 1944. Source: panzernet
The new fighting compartment that replaced the tank turret was visually the most obvious change. The new superstructure consisted of a large four-sided armored compartment (open from the top) with the main gun in it. The first 20 produced vehicles had double walls consisting of two 12 mm thick unhardened steel plates. The next 25 had double walls with two 10 mm armored plates. The remaining vehicles would be built using a single-thickness 25 mm armored plate (or 20 mm according to some sources). The superstructure of the first prototype was different from that of the production Möbelwagen. The side walls were distorted inward at the top, in contrast to the later production vehicle which had mostly flat sides. The two side armor plates were at first somewhat higher than the front and rear ones, but later on the production version, they were shortened by 250 mm. The front and rear plates also had two small hinged parts. These could be swung outwards and allow for the side plates to be fixed at an outward angle. Being an open top vehicle with only 25 mm of armor, the Möbelwagen offered only limited crew protection, mostly from shell fragments and small arms fire, but realistically ‘some’ armor is much better than none. What looks like pistol ports are located in the rear parts of the side walls and in the rear plate.
These double-walled (later single-walled) armored sides could, depending on the combat situation, be lowered to efficiently respond to any threat. In essence, this vehicle had two operational (moving and firing) ‘modes’ in which it could be used. In moving mode, the armored walls were fully raised and the gun could not be used properly. This mode was employed when moving from one location to another, protecting the crew and the gun. The second one was the firing position, with fully or partially lowered walls. When the walls were partially lowered (at 30°), the Möbelwagen crew could engage high flying enemy aircraft with some protection from shell fragments and small arms fire. When the sides were fully lowered, the crew could engage low flying aircraft and, if necessary, ground targets. The gun crew (in this situation) had only the gun shield for protection and were otherwise totally exposed to enemy fire.

Only when all sides were lowered could the crew engage ground targets and low flying aircraft but, in that case, they were totally exposed to enemy fire. The crew member on the right is using a rangefinder. Source:panzernet
The crew consisted of the commander, two gunners, a loader, a driver and a radio operator. Sometimes a seventh crew member is mentioned in some sources. The crew had a hard time to lift the sides back in vertical position. It might seem easy, but the total weight of each of these side walls was a few hundred kilograms.

Flakpanzer IV (3.7 cm Flak 43) ‘Möbelwagen’ illustrated by Tank Encyclopedia’s own David Bocquelet

3.7 cm Flak 43

The main weapon chosen for the Möbelwagen was the relatively new but powerful 3.7 cm Flak 43. In order to use the crew space as efficiently as possible, the right-side gun shield was shortened. When in transport mode (with fully raised walls), in case of danger or emergency, the gun could be used with a very limited firing arc. But, in order to use it efficiently, the side walls had to be lowered. Some imaginative crews (on few occasions) removed parts of the front armor in order to use the main gun against ground targets when on the move. Only when the armored walls were dropped to a horizontal position could the main gun be traversed at 360 °. The elevation of the Flak 43 was – 7.5° to + 90° with the maximum rate of fire 250 rounds per minute (but 150 was the more practical rpm). Besides their personal weaponry, the crew could have one MG.34 or MG.42 machine gun (carried inside the vehicle) for self-defense.

Some crew members were imaginative and had cut some parts of the frontal armor so the gun could engage ground targets without lowering the walls. The traverse arc was very limited, but at least there was some armor to hide behind. Source: panzernet
Although sharing the same 3.7 cm caliber as the earlier Flak 18, 36 and 37 models, the newer Flak 43 was a completely different weapon. The primary goal of this design was to be simple to operate and easy to produce. It had a new gas operated breech mechanism which was loaded with a fixed loading tray with eight round clips. This system nearly doubled the rate of fire. The mounting was also a simplified three-legged platform, similar to the earlier models.
Beside the single-gun version, a twin-gun version was also used by the German Army. The second gun was mounted above the first, not side by side. In order to do so, a stronger and heavier mounting was built (using a four wheel chassis). This was somewhat unusual, but it was probably done in order to be as simple as possible.
The production began in February 1944. Until the end of the war, some 6.103 (300-390 dual version) Flak 43 AA guns were built by the Rheinmetall-Borsig.
Specifications of the Weapon
Calibre: 37 mm/1.46 in
Traverse: 360°
Elevation: – 7.5° to + 90°
Weight in action: 1248 kg/2752 lbs
Rate of fire: 150-180 (practical) / 250-300 (max rate of fire)
Muzzle velocity: 820 mps/2690 fps
Maximum ceiling: 4800 m/15755 ft
Effective ceiling: 4200 m/13780 ft

In Combat

The first Möbelwagens built (possibly up to four vehicles) were sent to Denmark in March 1944 for test trials. These tests were conducted by a group of German Army anti-aircraft artillery staff. The tests showed that there were no major problems with the Flak 43 weapon and it worked fine. The only problem was with the exhaust gases during firing. There were some issues with the poor quality of the gunpowder used in the ammunition. A fully operated and enclosed turret was preferred for the Flakpanzer project but, because of the great necessity for such vehicle to be available as soon as possible, the ‘green light’ was given.
When sufficient numbers of Möbelwagen were built (by June 1944), they were used to equip the 9th, 11th, and 116th Panzer Divisions (on the Western front) with eight Möbelwagen vehicles each (Flugabwehrzug). The next units that received this vehicle were the 6th and 19th Panzer Divisions, both stationed on the Eastern front from July 1944. In August and September 1944, many Panzer Brigades (from 101st to 110th) received smaller Flugabwehrzuge with only four Möbelwagens each. By the end of the war, many more units on both front would receive Möbelwagens. From September 1944 on, several new mixed Flugabwehrzuge were formed with Möbelwagens and the new ‘Wirbelwind’ anti-aircraft tank (not many were built).

The sides could be partially lowered. In this case, high flying aircraft could be targetted and the crew would have some protection.
There is little information regarding the combat effectiveness of the Möbelwagen. The Möbelwagen fulfilled several roles requested earlier by the German military officials. The problem with the mobility of anti-aircraft guns was solved, as the Möbelwagen could follow the Panzer Divisions on any terrain. It also had an effective and strong gun. The biggest drawback to this vehicle was the fact that the side walls had to be lowered in order to engage enemy aircraft efficiently. While the crew lowered the sides, valuable time was wasted if it needed to engage enemy planes. It was also a hindrance if the vehicle needed to get on the move in a hurry, for example if it was attacked by enemy infantry. But, despite this, it was a welcome addition to the Panzer Divisions who desperately needed such a vehicle.

During the second half of the war, the Germans lost the control over the sky so camouflage was necessary for survival even for anti-air vehicles. Source: panzernet
The Möbelwagen was considered a stopgap vehicle that was to be eventually replaced with the more advanced Wirbelwind and the Ostwind. Both these vehicles had a new enclosed (only top was open) turret which offered much better crew protection. But neither of these two versions were ever built in sufficient numbers to make a difference during the war. There were some plans to arm the Möbelwagen with the twin barrel Flak 43 to increase the firepower, but nothing came of the idea.

Production

Most sources state that around 240 Möbelwagens were built during the war. However, there is no agreement in this respect. Bryan Perrett (New Vanguard) states that a total of 211 Möbelwagen were built. According to Walter J. Spielberger, only 205 were built. The authors Chris Mcnab and Werner write that around 240 vehicles had been built. Some internet websites claim that 250 vehicles were built. A number of the Möbelwagens were built using damaged tanks returned to Germany for repairs from all fronts. This makes it difficult to determine the exact number of vehicles built.

Specifications
Dimensions	5.41 x 2.88 x 2.68 m (17.7×9.4×8.8 ft)
Total weight, battle ready	25 tons
Crew	5
Armament	1x 3.7 cm (37mm) Flak 43 Anti-Aircraft gun
Armor	From 15 to 65 mm (0.59-2.56 in)
Propulsion	Maybach V12 gasoline HL 120 TRM (220 kW) 300 [email protected] rpm
Suspension	Leaf springs
Speed on /off road	42/16 km/h (26/9.9 mph)
Range (road/off road)	200 km (120 mi)
Total production	240

Links, Resources & Further Reading

Naoružanje drugog svetsko rata-Germany, Duško Nešić, Beograd 2008.
Panzerkampfwagen IV Medium Tank 1936-1945, Bryan Perrett, New Vanguard 2007.
Waffentechnik im Zeiten Weltrieg, Alexander Ludeke, Parragon books.
Kraftfahrzeuge und Panzer, der Reichsehr, Werhmacht und Bundeswehr ab 1900, Werner Oswald 2004.
PANZER TRACTS No.12 Flak Selbstfahrlafetten. Thomas L. Jentz.
German Artillery of World War Two, Ian V.Hogg,
Military Vehicles, Chris Mcnab,
Fighting men of WW II, Axis Forces, David Miller, Chartwell Books 2011.
Armor at war series, German self-propelled guns, Gordon Rotman.
Gepard, The history of German Anti-aircraft tanks, Valter J. Spielberger, Bernard & Graefe Verlag Munchen 1982.
www.panzernet.net

German Reich (1939)
Half-track Self-Propelled Anti-Aircraft Gun – 750 Built

The most famous German self-propelled anti-aircraft guns (SPAAG) are the Panzer IV based Wirbelwind, Ostwind, Mobelwagen and even Kugelblitz. However, despite being overshadowed by their tank-based counterparts, it was actually the half-track SPAAGs that made up the bulk of the German mobile anti-aircraft fleet. Thousands of such lightly armored vehicles were built, based on different chassis and with different gun combinations.
One of the earliest examples of such a vehicle is the Sd.Kfz.7/1, a version of the ubiquitous half-tracked tractor armed with a 2 cm Flakvierling 38 anti-aircraft gun system.

An early Sd.Kfz.7/1 undergoing trials, with the Flakvierling gun system covered. Notice that the tarpaulin covering the driver’s compartment is fitted. Also notice the early mesh drop-sides and the tools attached to them. Source: https://www.worldwarphotos.info/gallery/germany/halftracks/sdkfz-7/sdkfz-7-armed-with-a-2-cm-flakvierling-38-flak/

The Sd.Kfz.7

The Sd.Kfz.7, or Mittlerer Zugkraftwagen 8t (Medium Tractor 8 tonnes), was developed as part of the larger family of German half-tracks. The first specifications for this vehicle were laid down in 1932 by Wa.Prüf.6. The vehicle was developed by Krauss-Maffei, with the first vehicle entering production in 1933.
As the designation suggests, the Sd.Kfz.7 was meant to tow weights of up to 8 tonnes. It was the tow vehicle of choice for the famous Flak 88 anti-aircraft guns, the 15 cm sFH 18 howitzer, and the 10.5 cm K18 field gun. However, due to the chaos of war, these vehicles were sometimes seen towing larger loads. They also towed trucks and even light tanks through the harsh conditions on the Eastern Front. The Sd.Kfz.7 could also carry up to 18 men on its 3 benches. The rear of the vehicle was compartmentalized in order to carry various equipment, fuel and ammo.
The design constantly evolved during its 11 year production period. Several engines were used, with various changes made to the superstructure and suspension, including the addition of an extra pair of roadwheels with the last model, the Typ m 11, in order to reduce ground pressure.
In total, 12,000 Sd.Kfz.7 half-tracks were built by Kraus-Maffei, Daimler-Benz, and Hansa-Lloyd in Germany, Saurer in Austria, and Breda in Italy until 1944. They served on all front with the German Wehrmacht, as well as with Italy, Bulgaria, Hungary, and even the Yugoslav Partisans. Some were even used after the war by the Allies and the British tried to copy the design with the Traclat.

An Sd.Kfz.7 Typ m 11 towing an 88 mm Flak gun on a Sonderanhänger 201 trailer. This was a large and powerful vehicle and made a good basis for a SPAAG. Source: Aviarmor.net.

The Sd.Kfz.7/1

The Sd.Kfz.7/1, also known as the ‘Selbstfahrlafette auf m.Zgkw.8t (Sd.Kfz.7/2) mit 2cm Flakvierling 38’, was born shortly after the 2cm Flakvierling 38 was presented to Adolf Hitler in October 1939. The Luftwaffe ordered 100 such weapons systems to be mounted on the Sd.Kfz.7 chassis. Production started in February 1940 and continued until December 1944, by which time between 750 and 800 were manufactured. This made the Sd.Kfz.7/1 one of the most numerous SPAAGs the Germans had at their disposal.

The prototype Sd.Kfz.7/1. The pivot mounting used on the initial vehicles is very visible in this photo. The Flakvierling is lacking its full gun shield. Source: Panzer Tracts 12
The rear two bench rows were removed, as was the luggage compartment. In their place, a flat platform was created, with the gun mount in the center. A bench row was placed at the front of the platform, facing rearwards. The platform had three drop-sides. These were vertical when the vehicle was on the move, creating a space for the gun crew to stay in. When in firing position, these were dropped into a horizontal position, thus enlarging the space the crew had to move in. The rear drop-side also had a small ladder that helped the crew climb or descend from the platform. There were two kinds of drop sides used. For most Sd.Kfz.7/1 vehicles, these consisted of wire mesh fixed on a metal frame. Some of these metal frames had diagonal braces. However, vehicles built late in the war had these made of wood on a metal frame. This was probably done in order to save materials.
The windshield could be dropped down in order to allow a larger arc of fire for the gun. A tarpaulin could be added to give some cover from the elements, but it only covered the driver’s section.
The winch placed under the vehicle seems to have been retained. It was used to pull vehicles or guns that had gotten stuck.

The Sd.Kfz.7/1 at Koblenz. This vehicle is a reconstruction, being based on a regular Sd.Kfz.7 recovered from France. It is a late version with an armored cab and wooden drop sides. Some tools are strapped to the bonnet. Source: https://forum.valka.cz/topic/view/11838/2-cm-Flakvierling-38-auf-Sd-Kfz-7-Sd-Kfz-7-1
After August 1943, the vehicle was up-armored using 8 mm steel plating (although production of the unarmored version continued in parallel) and the official designation also changed to ‘Selbstfahrlafette mitgepanzertem Fahrerhaus (Self-propelled gun carriage with armored cab) auf m.Zgkw.8t (Sd.Kfz.7/1) mit 2cm Flakvierling 38’. However, only certain sections of the vehicle were protected. There were two plates at the front of the vehicle, covering the radiator and the engine from frontal fire. The sides were completely exposed. A new armored cab was also added, protecting the driver’s position and the rear crew’s bench. It was partly open to the rear. The top part was only 1.5 mm thick. There were four vision ports protected by armored shutters, two in the front windscreen and two in the side doors. The forward armored shutters had glass vision blocks built in. There were also two hatches in the roof of this armored compartment. There was an armored firewall between the driving compartment and the engine compartment. The armor weighed 2.2 tons. There were plans to prepare a lighter armored cab weighing only 800 kg.
Tools could be carried on the outside of the drop-sides, like a shovel or a pickaxe. However, these are absent in a large number of contemporary photos. Tools are also often depicted as being mounted on the engine hood on the up-armored vehicles, but, yet again, photographic evidence is lacking. One vehicle, restored by Krauss-Mauffei and stored at least for a time at Koblenz, features these hood-mounted tools.
The gun system was mounted in the middle of the rear platform. There were no less than 4 gun mountings used during production. The first one was a small tripod that was height adjustable. Then, the gun system was mounted on a pivot which was also height adjustable. The third mounting is unclearly described in the literature. However, on later vehicles, a new mounting system was added, which allowed the mounting of the gun system using its usual tripod. This had the advantage of easily allowing the Flakvierling to be dismounted and placed on the ground, but this option seems to have been rarely used. The tripod mount was bulkier and occupied more space than the pivot mount.

The later type gun mount. It could accommodate the Flakvierling directly on its tripod mounting. Source: Wheels & Tracks 12

A late Sd.Kfz.7/1 showing the tripod mount of the Flakvierling. This allowed the gun to be easily dismounted from the vehicle with the use of a crane. Source: Pinterest
The Sd.Kfz.7/1 also towed a Sd.Ah.56 special trailer. This was a two-wheeler trailer specially designed for carrying the ammo boxes and accessories for the Flakvierling AA gun system.
120 boxes of ammunition carrying 20 rounds each for a total of 2400 rounds were carried. 30 magazines were carried in the vehicles itself, with the other 90 being kept in the trailer. However, in operations, ammo boxes were scattered all around the rear platform, in order to allow easy access to the loaders.
A large number of chassis were also produced without the gun, meant to act as munition carriers. However, they had all the fittings needed to receive a gun and also acted as reserve chassis. It is unclear if these vehicles are included in the total production number or not.

A late version Sd.Kfz.7/1 with its Sd.Ah.56 trailer. Note the large amount of vegetation used as cover. Also, the steps are visible on the rear drop-side. These were used to access the platform. Source: Bundesarchiv via Wikimedia Commons

Automotive

The Sd.Kfz.7/1 kept all the automotive parts from the Sd.Kfz.7 half-track. The SPAAGs were based on the KM m 11 or the HM m 11 versions, the last in the evolution of the Sd.Kfz.7.
The original engine was a Maybach HL 62 TUK, although this was changed in 1943 for the HL 64 TR. The difference between the two was the displacement (6.4 liters instead of 6.2 liters) and the change of the lubrication system. Both were 6-cylinder water cooled gasoline engines. The HL 62 could reach a maximum of 140 hp at 2600 rpm. It could power the Sd.Kfz.7/1 to a maximum speed of 50 km/h. The 203-liter fuel tank gave a range of 250 km on road.
The engine was connected to a 5-speed differential gearbox (4 forward, 1 reverse) that powered the drive sprockets mounted at the front of the track. This was an “Aphon” type non-synchromesh gearbox. The clutch was a Mocano K 230 K. Seven pairs of interleaved rubberized roadwheels provided contact with the ground and also held the track on the return run. Six of the roadwheel pairs were sprung using a leaf spring suspension. However, the last pair, which also acted as the idler, had a torsion bar suspension instead.

One of the suspension units of an Sd.Kfz.7. Four pairs of roadwheels were connected to this leaf spring. Another two pairs were connected to another leaf spring, while the last pair was connected to a torsion bar suspension. Image courtesy of the Sd.Kfz.7 Project Part Search https://www.facebook.com/sdkfz7/
Steering was achieved using the front two wheels. These were air-filled rubber wheels that were steered using the steering wheel in the driver’s cabin. The tracks could also be powered separately in order to help turning, but this was used only if the steering wheels were insufficient. The front wheels had a leaf-spring suspension

The 2cm Flakvierling 38

The Flakvierling 38 anti-aircraft mount system was introduced into service in 1940. It was developed by the Mauser company for the Kriegsmarine at first but was then adopted by the Wehrmacht in order to provide an anti-aircraft system with a better rate of fire. It consisted of four 2cm Flak 38 AA guns mounted together, two on each side. This allowed the Flakvierling to put up four times more bullets in the same amount of time compared to the single Flak 38, thus increasing the chances of severely damaging enemy airplanes.
Inadvertently, this also made the gun quite potent against ground targets, as it was able to saturate enemy positions with fire.

A color (or colorized) image of a Sd.Kfz.7/1 in a very warm climate. Notice the vegetation piled up around the vehicle to provide some sort of cover. Source: https://forum.valka.cz/topic/view/11838/2-cm-Flakvierling-38-auf-Sd-Kfz-7-Sd-Kfz-7-1
There was no central loading system and each gun had its own 20 round magazine. The magazines were mounted on the sides of the system. When the system was at 0 degrees elevation, the magazines were horizontal.
The guns had a maximum range of 4.7 km and a maximum altitude range of 3.7 km. The combined maximum rate of fire of the 4 guns was 1800 rounds per minute, but this was usually closer to 800 rpm in operation, as the guns needed to be reloaded after they finished their magazines. It could take as little as 3 seconds to fire off all four magazines. Special compartments for the magazines were present on either side of the mount, rotating along with the whole system. The gun barrels could be removed for cleaning.
The guns were fired with the use of two-foot pedals. Each pedal fired two diagonally-opposed gun, so the upper-left at the same time as lower-right. This was done in order to balance out the firing recoil. If a pedal would have controlled the guns on one side, then the recoil from firing them would have rotated the mount to one side, thus making it impossible to aim. If the pedal would have controlled the guns on the upper part, the recoil would have pulled the system upwards, again throwing off the gunner. With the guns fired in diagonal pairs, the recoil compensated both horizontally and vertically, allowing the gunners to aim properly at their target. An official order was issued to Flakvierling 38 crews to only fire two barrels at a time, but this recommendation was mostly ignored in the field.

An Sd.Kfz.7/1 gun crew looking after one of its targets prior to the Battle of Kursk, 1943. Notice the large amounts of vegetation used as camouflage. Source: ww2dbase, German Federal Archive
The aiming system consisted of either a Flakvisier 38 or a Flakvisier 40. They differed in minor details. These were electrical devices which used batteries to adjust the sights in order to help the gunners aim.
The Flakvierling could rotate 360 degrees, with elevation ranging from -8 to 85 degrees. Both rotation and elevation were done manually. The first Sd.Kfz.7/1 were not produced with a gun shield, but this was introduced quite early and retrofitted to older vehicles. The guns were protected by a 3-part shield, with the outer sides being dismountable. The shield weighed 325 kg. These offered the gunners and loaders a degree of protection from rifle-caliber bullets. For land use, the whole system sat on a static tripod which had a ring on which the system rotated. When used on ships, the system sat on a pivot. No fewer than 10 men were needed to crew the Sd.Kfz.7/1, with a driver, a commander and 8 gun servants.

A well worn early Sd.Kfz.7/1. The Flakvierling is lacking two of its barrels. The vehicle has received a coat of white-wash as camouflage. Notice the wire mesh drop sides and the tools still attached to it.
Source: https://forum.valka.cz/topic/view/11838/2-cm-Flakvierling-38-auf-Sd-Kfz-7-Sd-Kfz-7-1
By the end of the war, the Flakvierling became less efficient against the newer versions of the Allied and Soviet ground attack planes, thus falling out of favor and being replaced by 3.7 cm guns. This was probably one of the reasons why the Sd.Kfz.7/1 was discontinued in 1944.

SdKfz-7/1 Flakvierling by Tank Encyclopedia’s own David Bocquelet

SdKfz-7/1 with armoured cab by Tank Encyclopedia’s own David Bocquelet

Markings and Camouflage

* Most of this information comes from photographic records.
The early war vehicles seem to have been painted in the regular Dunkelgrau color used for most German army vehicles at the time. Three license plates were fitted to the vehicle, two on the front bumper and one at the rear. No other markings seem to be present on the vehicles.
During winter, the Sd.Kfz.7/1 were white-washed in order to make them harder to detect by enemy pilots and ground troops.
The vehicles soon acquired various camouflage schemes, although it is unclear if these were regulated or purely the crew’s choice. A set of full-color pictures taken in Czechoslovakia in May 1945 of the surrender of the I. Flak-Korps show a number of Sd.Kfz.7/1 SPAAGs in green-sand camouflage colors, although the patterns are quite random.

Two uparmored Sd.Kfz.7/1s from the I.Flak Korps surrendering in Czechoslovakia in May 1945. These are original color photos and beautifully show the camouflage colors used. Source: https://www.network54.com/Forum/571595/thread/1504613838/last-1504613838/myfile.htm
An interesting feature on a number of vehicles is that the gun shield was covered with cloth, probably in order to minimize reflections that might give the vehicle’s position away. Also, large amounts of vegetation were used to camouflage the vehicle and make it harder to see from the air.
Markings were quite rare. One vehicle was photographed with kill marks on the gun shield, indicating the number of plane and ground vehicle kills the crew claimed. One other late-style vehicle has the nickname ‘Dorle’ written on the radiator armor plating. Another vehicle, from a leichte Flak-Btl., had some markings denoting its unit on the front fenders. An up-armored Sd.Kfz.7/1 had unit markings on the right cab door. However, these occurrences were the exception and not the rule.

An Sd.Kfz.7/1 with the gun shield covered by cloth sitting in a cereal field. This was meant to remove any reflections from the metal shield which could give away the position of the gun system. The two sunflowers are also an interesting addition. Source: German Self Propelled Guns, Armor at War series 7022

An Sd.Kfz.7/1 also surrendering in Czechoslovakia. Notice the ‘Dorle’ nickname stenciled on the front armor plate. Source: https://www.network54.com/Forum/571595/thread/1504613838/last-1504613838/myfile.htm

Operational Use

The Sd.Kfz.7/1 was used by the Flak Kompanies and Flak Batteries of the Luftwaffe. These were used to accompany the Wehrmacht’s divisions or to protect important locations and installations like airfields. Two or three Sd.Kfz.7/1 SPAAGs formed a platoon. After 1943, a three-vehicle platoon was also added to the HQ unit of each Panzer Abteilung. This gave the tank units their own AA support, without having to rely on the Luftwaffe’s.
These vehicles were very well suited to accompany the German Panzer formations, as they could keep up with the tanks. Also, they could deploy very quickly, immediately providing cover for the troops in case of an unexpected air attack. A towed AA gun would first have to be taken off its trailer and then be placed on its mounting, which would take precious time during an attack. Also, the Sd.Kfz.7/1 could withdraw quickly if the situation required it, with little preparation required. As a trade-off, the Flakvierling could be towed by far smaller vehicles, meaning that the creation of a SPAAG meant the loss of a powerful tractor which could be used to tow a heavier piece of ordnance. This was especially important given the fact that, throughout WWII, the Wehrmacht was reliant on horses to tow their heavy ordnance, as there were never enough heavy tractors.
Their very high rate of fire made them a significant threat to enemy ground attack aircraft. Besides their potential to destroy the attackers, their presence could make enemy pilots hesitate or rush their attack runs, thus lowering their chances of success.
The Sd.Kfz.7/1 had a very high silhouette. Besides obviously making it more visible, this also made it harder to dug-in compared to the towed Flakvierling, as the whole tractor had to be accommodated under cover. Also, for the up-armored vehicles, the guns could not fire directly in front of the vehicle, creating a blind spot.
However, their lack of armor meant that they had to avoid enemy ground forces, as the initial batches of vehicles were vulnerable to all small arms fire and to artillery shrapnel. Even the later vehicles, although up-armored, were only protected against small arms fire coming from the front.
Despite these flaws, the Sd.Kfz.7/1 found itself pressed into a role it was definitely not suited for: fighting against enemy ground forces. In the ground fire support role, the Flakvierling could be a serious threat to enemy infantry and unarmored vehicles due to its high rate of fire and high caliber. Also, when using AP rounds, the Flakvierling could penetrate light armored vehicles such as armored cars or the shields of AT guns. When used in this role, the vehicle was driven in reverse, with the gun having a free field of fire towards the enemy. This did offer the advantage of a quick getaway if needed. Also, the armor of the vehicle was definitely insufficient for the task, with the crew members, especially the loaders, being protected only by the gun shield.

An Sd.Kfz.7/1 on the Eastern Front, being used in a counter-attack against Soviet forces. The vehicle is being driven in reverse, with the gun facing towards the rear. Note that it is an early type vehicle, with no armor whatsoever except the gun shield. Source: Gepard: The History of German Anti-Aircraft Guns
The Sd.Kfz.7/1 soldiered for most of the war, serving especially on the Eastern Front, but also in Africa, Italy and the Western Front after 1944. It is, as of now, unclear if these vehicles served in the invasion of France or Norway.
One famous occasion in which an Sd.Kfz.7/1 was used was during operation Market Garden. Then, a vehicle from an SS unit used its guns to fire at airdropped paratroopers while they were still in the air, but also at the supply gliders.

Surviving Vehicles

At least three Sd.Kfz.7/1 exist today in museums. One late version with the armored cab is at the Koblenz Armor Museum in Germany. This is not an original vehicle, but a reproduction. The base vehicle was an Sd.Kfz.7 recovered from a scrapyard in France where it had been used as a heavy load tractor. It was refurbished with the help of a number of German military defense companies, including Krauss Maffei (who paid for the reconstruction), MTU (engine), ZF Friedrichshafen (transmission), and Clouth (roadwheels).
A second vehicle is at the Sinsheim Technical Museum in Germany, being an early unarmored version. The gun shield is probably a later addition and does not match the usual Flakvierling shield.
The third vehicle is at the Saumur Tank Museum in France. It is awaiting restoration and, while visually in a bad state, the chassis and automotive parts are claimed to be in good order. It is a late war version with the armored cab. The Flakvierling 38 on the back seems to be missing.

The Sd.Kfz.7/1 at the Sinsheim Technical Museum. Source: https://forum.valka.cz/topic/view/11838/2-cm-Flakvierling-38-auf-Sd-Kfz-7-Sd-Kfz-7-1

Sd.Kfz.7/1 at the Saumur Tank Museum, awaiting restoration. Image courtesy of Christophe Mialon.

Sd.Kfz.7/1
Dimensions (L-W-H)	6.85 x 2.35 x 2.62 m (22.6 x 7.9 x 8.7 ft)
Total weight, battle ready	11.5 tons
Crew	1 Driver + gun team
Propulsion	Maybach HL 62 TUK, six-cylinder petrol
Suspension	Half-track torsion arms, interleaved wheels
Maximum speed	50 km/h (31 mph)
Armament	2cm Flakvierling 38
Total production	750

Links, Reources & Further Reading

Panzer Tracts No.12: Flak Selbstfahrlafetten and Flakpanzer, Thomas Jentz, 1998
Panzer Tracts No.22-5: Gepanzerter 8t Zugkraftwagen & Sfl. Flak (Sd.Kfz.7), Thomas Jentz
Gepard: The History of German Anti-Aircraft Tanks, Walter Spielberger, 1982
‘Sd.Kfz.7 turned 7/1’, Walter Spielberger, Wheels & Tracks 12, 1985
German Half-Tracked Vehicles of World War II, John Milsom, 1975
Panzer Regiments: Equipment and Organisation, W.J.K Davies, 1978
Information about the Flakvisier from Handbook on German Military Forces, US War Department, 1945
20 mm Flak 38 on WW2-Weapons, written by WW2-Weapons team, consulted 29 December 2017
Deutsche Artillerie-Geschuetze, Alexander Lüdeke
War Office Tech Intell Summary No. 151, November 8th 1944
ETO Ordnance Technical Intelligence Report No.220, 11 April 1945
Special thanks to the Sd.Kfz.7 Project Part Search for information about the suspension, to Mr. Hilary Louis Doyle for naming information, to Christophe Mialon for information about the vehicle at Saumur
Special thanks to Hunter12396, CaptianNemo, Craig Moore and Marcus Hock for help in searching for information and sources