The Flakpanzer IV/3.7cm Flak, more popularly known as Ostwind, was designed to replace the Wirbelwind. All flakpanzers based on the Panzerkampfwagen IV chassis were to ultimately be supplanted by the Kugelblitz. Production delays in that program, however, meant that stopgap weapons had to be used and manufactured right up until the end of the war (as only two Kugelblitz were ever completed with seven Kugelblitz chasses going to Ostwind production).
The 3.7cm FlaK 43 was far superior an anti-aircraft weapon than the 2cm Flakvierling 38, and production of the Ostwind quickly supplanted that of the Wirbelwind beginning in December 1944. Only a total of 43 production examples were completed before the end of hostilities, with 36 of these having been converted from older Panzerkampfwagen IV (hence the appearance of zimmerit on vehicles produced after its use had been discontinued).
In spring of 1944, the Inspector for the Panzer Troops (In 6) indicated that current flakpanzers in the Wehrmacht inventory were unsatisfactory, and that new vehicles should be developed with the following minimum requirements:
- rotating armored turret large enough to accommodate a three to four man crew.
- A 2000m effective range
- Twin guns
- A sufficient ammunition supply
- Maxiumum height, 3 meters
- Full radio equipment onboard.
The Wirbelwind design met most of these requirements. Vehicle height was kept low by recessing the gun mount into the top of the hull. The recess allowed for a smaller turret design and kept the overall vehicle height well under the 3 meter limit. Addition of a hydraulic traverse to the turret allowed a traversing speed of 60o/sec. A total of 3200 rounds for the four 2cm guns was carried (with storage for spare barrels provided on the sides of the engine compartment).
The Wirbelwind was developed as a conversion for Panzer IV chasses which had been returned from the front for rebuilding. Armored protection on the hull varied because the chasses used for conversion included Ausf F through Ausf G Panzerkampfwagen IV. As the 2cm Flakvierling was not as effective as the 3.7cm FlaK 43/1, the project was discontinued in autumn of 1944 after a total of 86 vehicles were converted.
The 2cm Flakvierling auf Fahrgestell Panzerkampfwagern IV, popularly known as the Möbelwagen, never actually entered volume production. The chassis was a simple conversion of the basic Panzerkampfwagen IV with a wider superstructure and large shields surrounding the 2cm Flakvierling 38. Hitler saw at least two demonstrations of the vehicle (in early 1943 and in October of 1943), but both times vetoed production. The chassis was ultimately used to create a Möbelwagen using the 3.7cm FlaK43.
Officially designated the 15cm Schwere Panzerhaubitze auf Geschützwagen III/IV (Sf), the "Hummel" was one of the more effective attempts to provide a self-propelled chassis for larger caliber artillery. Designed to provide artillery support panzer units, the Hummel was built on the same Panzer III/IV hybrid chassis as the "Nashorn" (armed with the 8.8cm PaK43/1 L71). This vehicle utilized a lengthened Panzer IV chassis, along with the running gear and 400mm tracks of a Panzer IV Ausf. F. The Drive system (drive sprockets, final drives, brakes, transmission, and engine)were all taken from the Panzer III Ausf. J. The engine fittings (fuel pump, filters, cooling fans, fan drives/belts, batteries, muffler and radiator) were a combination of Panzer III and Panzer IV components. The engine was moved amidships and a special narrow driver's compartment was fitted into the front plate. This narrow compartment was later replaced with a hull width compartment. Apparently though the old compartment provided better side- to-side visibility, communication was superior in the new compartment.
Hummel was only one of the many weapons which made its combat debut at Kursk in 1943. A total of 724 Hummels were eventually produced (though Hitler eliminated the name ‘Hummel' in late February, 1944) along with an additional 157 Munistionsträger (ammunition carriers sans main armament). Each panzer division was initially allocated six of the vehicles forming a single battery. Eventually some divisions received a second battery. The vehicle served until the end of the war with all Panzer Divisions.
During the planning stages before the outbreak of World War II, various methods of dealing with fixed fortifications were explored. One necessary vehicle, in the eyes of the Wehrmacht, was a bridge-layer. Early development projects were based on the Panzer I and Panzer II. The small size of these vehicles, however, sharply limited their utility. After good results had been obtained from experiments with a mild steel prototype, it was decided that a bridge-layer would be built on the Panzerkampfwagen IV. A total of four Ausf. C and 16 Ausf. D were converted into Brückenleger.
The bridge-layers were issued to the bridging platoons of the Panzer Divisions starting in March of 1940. During the campaigns in 1940, the Brückenleger served with the 1st, 2nd, 3rd, 5th and 10th Panzer Divisions. Production orders for an additional 48 bridge-layers were placed, but following the campaign in France and the Low Countries led to the cancellation of all further production. All of the vehicles were converted back into gun tanks by May of 1941.
The 10.5cm K18 auf Panzer Selbstfahrlafette Iva was another weapon designed to assault fixed fortifications. The large caliber gun was designed to assault fortified bunkers. Two prototypes were built by Krupp in March of 1941. Discussions with Hitler that May led to the suggestion that the vehicle should be developed as a heavy Panzerjäger alongside a proposed 12.8cm armed vehicle. Production of the vehicle was to begin in spring of 1942, but changing requirements ended the program.
The two prototypes were assigned to the 521st Panzerjäger Detachment for a planned assault on Gibraltar. As this attack never materialized, the vehicles were instead farmed out to the 3rd Panzer Division for operations in Russia. As the 10.5cm K18 gun was capable of penetrating 111mm of 30o armor or 132mm of vertical armor at a range of 2km, the vehicle met with considerable success against Soviet armor. The shape definitely foreshadows later self-propelled anti-tank vehicles. Clearly given the superior firepower of the 10.5cm gun, these vehicles in quantity would have certainly been a welcome addition to the Wehrmacht's arsenal during the pivotal battles of late 1941 and early 1942.
Additional Sources:
www.topedge.com
www.military-art.com
www.achtungpanzer.com
www.3-d-models.com
www.skalman.nu
