Flakpanzer IV (2 cm Flakvierling 38) ‘Wirbelwind’

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.

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.