The German tank force was a success due to tactical innovation more than tank quality.
Using so-called “Blitzkrieg” tactics, Guderian, Paul Ludwig Ewald von Kleist and other field commanders such as Rommel broke the hiatus of the Phoney War in a manner almost outside the comprehension of the Allied — and, indeed, the German — High Command. In actual tank-on-tank encounters the German armor performed poorly, but as a coherent unit, the combined arms tactic of the Blitzkrieg shocked the Allies.
The German Panzer forces at the start of World War II were not especially impressive. Only 4% of the defense budget was spent on armored fighting vehicle (AFV) production. Guderian had planned for two main tanks: the Panzer III, which was in production; and the Panzer IV with a 75 mm gun, which did not have one. The design work for the Panzer IV had begun in 1935 and trials of prototypes were undertaken in 1937, but by the time of the invasion of Poland only a few hundred ‘troop trial’ models were available. The development work was then halted and limited production was begun by Krupp in Magdeburg (Grusonwerk AG), Essen and Bochum in October 1939 with 20 vehicles built. However, even that low number could not be sustained, with production dropping to ten in April 1940. Production also dropped because metal was very expensive and not many citizens were donating it.
Nevertheless, the number of available Panzer IV’s (211) was still larger than that of the Panzer III (98). There were also technical problems with the Panzer III: it was widely considered to be under-gunned with a 37 mm KwK L/45 and production was split among four manufacturers (MAN, Daimler-Benz, Rheinmetall-Borsig, and Krupp) with little regard for each firm’s expertise, and the rate of production was initially very low (40 in September 1939, 58 in June 1940) taking until December 1940 to reach 100 examples a month. The Panzer force for the early German victories was a mix of the Panzer I (machine-gun only), Panzer II (20mm gun) light tanks, and two models of Czech tanks (the Panzer 38(t) and the Panzer 35(t)). By May 1940 there were 349 Panzer III’s available for the attacks on France and the Low Countries. Through superior command/control and tactics, the Germans were able to prevail in the Battle of France, despite the deficiencies of their Panzers.
That the Panzer III was undergunned was recognized during its conception and its design included a large turret ring to make it possible to fit a 2250 ft/s (656 m/s) 50 mm KwK L/42 gun on later models. In July 1940, too late to see action in the final weeks of the Battle of France, the first 17 of these models were produced. Designated the Panzer III Ausf. F, the other changes included an upgraded Maybach engine and numerous minor changes to ease mass production.
The Ausf. F was quickly supplanted by the Ausf. G[clarification needed], which was the main tank of the Afrika Korps in 1940–41 and also saw action in Yugoslavia and Greece. Around 2,150 Panzer IIIs were produced, of which around 450 were the Ausf G. These tanks were still under-gunned, poorly armored and mechanically overly-complex in comparison to equivalent British tanks. After fighting in Libya in late 1940 the Ausf. H was put into production with simpler mechanics, wider tracks and improved armor. In April 1941 there was a general ‘recall’ of the Panzer III to upgrade the main gun to the new 50 mm L/60, with the new Panzergranate 40 round, and muzzle velocity was pushed to 3875 ft/s (1,181 m/s). New tanks produced with this gun were designated Ausf. J.
The invasion of the Soviet Union in Operation Barbarossa signalled an enormous change in German tank development. In July 1941 36 Panzer and motorized infantry divisions were assigned to the invasion fielding over 3000 AFV’s. In June 1941, these tanks first encountered the Soviet T-34. The German tanks were outclassed in every aspect of battle performance. A little later the American-made M3 Lee and then M4 Sherman tanks were encountered in the Western Desert, the M4 outclassing German armor in that theater too.
As an immediate measure the Panzer III’s armor was upgraded to 70 mm by additional plates and spaced armor was introduced to protect against hollow charge attacks. Nonetheless, the Panzer III was clearly outclassed and production was ended in August 1943 with the Ausf. M (a conversion of older types), the vehicle having been up-gunned to a 75 mm L/24 and downgraded to a support role. The Panzer III chassis did continue to be made until the end of the war as the base of a range of special purpose vehicles like Sturmgeschütz III.
Slow production of the Panzer IV had been continuing, by the end of 1940 386 Ausf. Ds were in service and in 1941 a further 480 were produced, despite an order from the army for 2,200. The short 75 mm gun was the main advantage of the Panzer IV, weight and armor were close to that of the Panzer III. The Panzer IV became the most numerous tank of the Panzer divisions, although already outclassed in 1942 it was easy to maintain and simpler to produce than other German tanks. The Ausf. E was the major production variant, although the Ausf. F2 (later renamed Ausf. G) with a long high velocity gun was the more effective variant. First introduced in 1940 the 22 ton machine was progressively improved, with the addition of the L/43 gun the most significant change – it could penetrate 80 mm of armour at 1800 m. Later variants further improved the gun to a 75 mm L/48 but were mainly characterised by increasing the main armor and adding spacer and skirt armor to protect against anti-tank weapons. Zimmerit paste, to prevent magnetic charges attaching was also introduced on the Panzer IV. About 12,000 Panzer IV tanks (derived chassis included) were produced during the war, more than twice as many as the next German tank.
Despite continued efforts with the lighter tanks throughout the war the German designers did produce a direct counter to the heavier Allied tanks with the PzKpfw V, the Panther (in 1944 the PzKpfw designation was dropped and the vehicle was known simply as the Panther). Design work on the replacement for the Panzer IV had begun in 1937 and prototypes were being tested in 1941. The emergence of the T-34 led to an acceleration of this leisurely time-table. At the insistence of Guderian a team was dispatched to the eastern front in November 1941 to assess the T-34 and report. Three features of the Soviet tank were considered as most significant, top was the sloped armour all round which gave much improved shot deflection and also increased the armor thickness against penetration; second was the wide track and large road wheels that improved stability; and third was the long over-hanging gun, a feature German designers had avoided up to then. Daimler-Benz and MAN were tasked with designing and building a new 30–35 ton tank by next Spring. At the same time the existing prototype tanks were up-gunned to 88 mm and ordered into production as the PzKpfw VI, the Tiger.
The two T-34 influenced proposals were delivered in April 1942. The Daimler-Benz design was a ‘homage’ to the T-34, ditching the propensity for engineering excellence, and hence complexity, to produce a clean, simple design with plenty of potential. The MAN design were more conventional to German thinking and was the one accepted by the Waffenprüfamt 6 committee. A prototype was demanded by May and design detail work was assigned to Kniepkampf.
If the overhanging gun and sloping armor are ignored the Panther was a conventional German design: its internal layout for the five crew was standard and the mechanicals were complex. Weighing 43 tons it was powered by a 700 hp (522 kW) gasoline engine driving eight double-leaved bogie wheels on each side, control was through a seven-speed gearbox and hydraulic disc brakes. The armor was homogenous steel plate, welded but also interlocked for strength. Preproduction models had only 60 mm armor but this was soon increased to 80 mm on the production Ausf. D and later models had a maximum of 120 mm. The main gun was a 75 mm L/70 with 79 rounds, supported by one or two MG 34 machine guns.
The MAN design was officially accepted in September 1942 and put into immediate production with top priority, finished tanks were being produced just two months later and suffered from reliability problems as a result of this haste. With a production target of 600 vehicles a month the work had to be expanded out of MAN to include Daimler-Benz and in 1943 the firms of Maschinenfabrik Niedersachsen-Hannover and Henschel. Due to disruption monthly production never approached the target, peaking in 1944 with 330 a month and ending around February 1945 with at least 5964 built. The Panther first saw action around Kursk on July 5, 1943.
In addition to these mainstream efforts the German army also experimented with a variety of unusual prototypes and also put into production several peculiarities. Some Tiger tanks were fitted with anti-personnel grenade launchers that were loaded and fired from within the tank as an anti-ambush device.