|Type Medium tank|
In service 1939–1945
|Place of origin Nazi Germany|
Wars World War II
|Used by Nazi Germany Kingdom of Romania Slovak Republic Kingdom of Hungary Independent State of Croatia Turkey Norway|
The Panzerkampfwagen III, commonly known as the Panzer III, was a medium tank developed in the 1930s by Germany, and was used extensively in World War II. The official German ordnance designation was Sd.Kfz. 141. It was intended to fight other armoured fighting vehicles and serve alongside and support the Panzer IV; however, as the Germans faced the formidable T-34, more powerful anti-tank guns were needed, and since the Panzer IV had more development potential, it was redesigned to mount the long-barrelled 7.5 cm KwK 40 gun. The Panzer III effectively became obsolete in this role and was supplanted by the Panzer IV. From 1942, the last version of Panzer III mounted the 7.5 cm KwK 37 L/24, better suited for infantry support. Production of the Panzer III ended in 1943. However, the Panzer III's capable chassis provided hulls for the Sturmgeschütz III assault gun until the end of the war.
At the time, German (non-light) tanks were expected to carry out one of two primary tasks when assisting infantry in breakthroughs, and exploit gaps in the enemy lines where opposition had been removed, moving through and attacking the enemy's unprotected lines of communication and the rear areas. The first task was direct combat against other tanks and other armoured vehicles, requiring the tank to fire armour piercing (AP) shells. On January 11, 1934, following specifications laid down by Heinz Guderian, the Army Weapons Department drew up plans for a medium tank with a maximum weight of 24,000 kg (53,000 lb) and a top speed of 35 km/h (22 mph). It was intended as the main tank of the German Panzer divisions, capable of engaging and destroying opposing tank forces, and was to be paired with the Panzer IV, which was to fulfil the second use: dealing with anti-tank guns and infantry strong points, such as machine-gun nests, firing high-explosive shells at such soft targets. Such supportive tanks designed to operate with friendly infantry against the enemy generally were heavier and carried more armour.
The direct infantry-support role was to be provided by the turret-less Sturmgeschütz assault gun, which mounted a short-barrelled gun on a Panzer III chassis.
Daimler-Benz, Krupp, MAN, and Rheinmetall all produced prototypes. Testing of these took place in 1936 and 1937, leading to the Daimler-Benz design being chosen for production. The first model of the Panzer III, the Ausführung A. (Ausf. A), came off the assembly line in May 1937; ten, two of which were unarmed, were produced in that year. Mass production of the Ausf. F version began in 1939. Between 1937 and 1940, attempts were made to standardize parts between Krupp's Panzer IV and Daimler-Benz's Panzer III.
Much of the early development work on the Panzer III was a quest for a suitable suspension. Several varieties of leaf-spring suspensions were tried on Ausf. A through Ausf. D, usually using eight relatively small-diameter road wheels before the torsion-bar suspension of the Ausf. E was standardized, using the six road wheel design that became standard. The Panzer III, along with the Soviet KV heavy tank, was one of the early tanks to use this suspension design first seen on the Stridsvagn L-60 a few years earlier.
A distinct feature of the Panzer III, influenced by British Vickers tanks (1924), was the three-man turret. This meant that the commander was not distracted with another role in the tank (e.g. as gunner or loader) and could fully concentrate on maintaining awareness of the situation and directing the tank. Most tanks of the time did not have this capability, providing the Panzer III with a combat advantage versus such tanks. For example, the French Somua S-35's turret was manned only by the commander, and the Soviet T-34 originally had a two-man turret crew. The Panzer III, as opposed to the Panzer IV, had no turret basket, merely a foot rest platform for the gunner.
The Panzer III was intended as the primary battle tank of the German forces. However, when it initially met the KV-1 and T-34 tanks it proved to be inferior in both armour and gun power. To meet the growing need to counter these tanks, the Panzer III was up-gunned with a longer, more powerful 50-millimetre (1.97 in) gun and received more armour but still was at disadvantage compared with the Soviet tank designs. As a result, production of self-propelled guns, as well as the up-gunning of the Panzer IV was initiated.
In 1942, the final version of the Panzer III, the Ausf. N, was created with a 75-millimetre (2.95 in) KwK 37 L/24 cannon, the same short-barreled howitzer-like gun used for the initial models of the Panzer IV, a low-velocity gun designed for anti-infantry and close-support work. For defensive purposes, the Ausf. N was equipped with rounds of HEAT ammunition that could penetrate 70 to 100 millimetres (2.76 to 3.94 in) of armour depending on the round's variant, but these were strictly used for self-defence.
The Japanese government bought two Panzer IIIs from their German allies during the war (one 50 mm and one 75 mm). Purportedly this was for reverse engineering purposes, since Japan put more emphasis on the development of new military aircraft and naval technology and had been dependent on European influence in designing new tanks. By the time the vehicles were delivered, the Panzer III's technology was obsolete.
The Panzer III Ausf. A through C had 15 mm (0.59 in) of rolled homogeneous armour on all sides with 10 mm (0.39 in) on the top and 5 mm (0.20 in) on the bottom. This was quickly determined to be insufficient, and was upgraded to 30 mm (1.18 in) on the front, sides and rear in the Ausf. D, E, F, and G models, with the H model having a second 30 mm (1.18 in) layer of face-hardened steel applied to the front and rear hull. The Ausf. J model had a solid 50 mm (1.97 in) plate on the front and rear, while the Ausf. J¹, L, and M models had an additional layer of offset 20 mm (0.79 in) homogeneous steel plate on the front hull and turret, with the M model having an additional 5 mm (0.20 in) Schürzen spaced armour on the hull sides, and 8 mm (0.31 in) on the turret sides and rear. This additional frontal armor gave the Panzer III frontal protection from most British and Soviet anti-tank guns at all but close ranges. However, the sides were still vulnerable to many enemy weapons, including anti-tank rifles at close ranges.
The Panzer III was intended to fight other tanks; in the initial design stage a 50-millimetre (1.97 in) gun was specified. However, the infantry at the time were being equipped with the 37-millimetre (1.46 in) PaK 36, and it was thought that, in the interest of standardization, the tanks should carry the same armament. As a compromise, the turret ring was made large enough to accommodate a 50-millimetre (1.97 in) gun should a future upgrade be required. This single decision later assured the Panzer III a prolonged life in the German Army.
The Ausf. A to early Ausf. F were equipped with a 3.7 cm KwK 36 L/45, which proved adequate during the campaigns of 1939 and 1940, but the later Ausf. F to Ausf. J were upgraded with the 5 cm KwK 38 L/42 and the Ausf. J¹ to M with the longer 5 cm KwK 39 L/60 gun in response to increasingly better armed and armoured opponents.
By 1942, the Panzer IV was becoming Germany's main medium tank because of its better upgrade potential. The Panzer III remained in production as a close support vehicle. The Ausf. N model mounted a low-velocity 7.5 cm KwK 37 L/24 gun - the same used by the early Panzer IV Ausf. A to Ausf. F models. These guns had originally been fitted to older Panzer IV Ausf A to F1 models and had been placed into storage when those tanks had also been up armed to longer versions of the 75 mm gun.
All early models up to and including the Ausf. F had two 7.92-millimetre (0.31 in) MG 34 machine guns mounted coaxially with the main gun, and a similar weapon in a hull mount. Models from the Ausf. G and later had a single coaxial MG34 and the hull MG34.
The Panzer III Ausf. A through C were powered by a 250 PS (184 kW), 12-cylinder Maybach HL 108 TR engine, giving a top speed of 32 km/h (20 mph) and a range of 150 km (93 mi). All later models were powered by the 300 PS (221 kW), 12-cylinder Maybach HL 120 TRM engine. Regulated top speed varied, depending on the transmission and weight, but was around 40 km/h (25 mph).
The fuel capacity was 310 l (68.2 gal), and while extra fuel could be carried in an auxiliary fuel over the rear, this was not often employed. Range on the main tank was 145 km (90 mi) to 155 km (96 mi) on road, or 95 km (59 mi) crosscountry.
The Panzer III was used in the campaigns against Poland, France, the Soviet Union and in North Africa. A handful were still in use in Normandy, Anzio, Norway, Finland and in Operation Market Garden in 1944.
In the Polish and French campaigns, the Panzer III formed a small part of the German armoured forces. Only a few hundred Ausf. A through F were available in these campaigns, most armed with the 37-millimetre (1.46 in) gun. They were the best medium tank available to the Germans and outclassed, in both firepower and armour, most of their opponents, such as the Polish 7TP, French R-35 and H-35 light tanks and the Soviet T-26 light tank and BT cavalry tanks.
Around the time of Operation Barbarossa, the Panzer III was numerically the most important German tank. At this time, the majority of the available tanks (including re-armed Ausf. E and F, plus new Ausf. G and H models) had the 50-millimetre (1.97 in) KwK 38 L/42 cannon, which also equipped the majority of the tanks in North Africa. Initially, the Panzer IIIs were outclassed by Soviet T-34 and KV tanks. However, the most numerous Soviet tanks were the T-26 and BT tanks. This, along with superior German tactical skill, crew training, and the good ergonomics of the Panzer III all contributed to a favourable kill ratio for German tanks of all types in 1941.
With the appearance of the T-34 and KV tanks, rearming the Panzer III with a longer, more powerful 50-millimetre (1.97 in) gun was prioritised. The T-34 was generally invulnerable in frontal engagements with the Panzer III until the 50 mm KwK 39 L/60 gun was introduced on the Panzer III Ausf. J¹ in the spring of 1942 (the gun was based on infantry's 50 mm Pak 38 L/60). This could penetrate the T-34 frontally at ranges under 500 metres (1,600 ft). Against the KV tanks, it was a threat if armed with special high velocity tungsten rounds. In addition, to counter anti-tank rifles, in 1943 the Ausf. L version began the use of spaced armour skirts (Schürzen) around the turret and on the hull sides. However, due to the introduction of the upgunned and uparmoured Panzer IV, the Panzer III was, after the Battle of Kursk, relegated to secondary roles, such as training, and it was replaced as the main German medium tank by the Panzer IV and the Panther.
The Panzer III chassis was the basis for the turretless Sturmgeschütz III assault gun, one of the most successful self-propelled guns of the war, and the single most-produced German armoured fighting vehicle design of World War II.
By the end of the war, the Panzer III saw almost no frontline use and many vehicles had been returned to the factories for conversion into StuG assault guns, which were in high demand due to the defensive warfare style adopted by the German Army by then.