Panzer III
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 similar Panzer IV, which was originally designed for infantry support.
Panzerkampfwagen III
Sd.Kfz. 141
1939–1945
1935–1937
Daimler-Benz
103,163 ℛ︁ℳ︁ (Ausf. M)
1939–1943
5,774 (excluding StuG III)
23.0 tonnes (25.4 short tons)
5.56 m (18 ft 3 in)
2.90 m (9 ft 6 in)
2.5 m (8 ft 2 in)
5 (commander, gunner, loader, driver, radio operator/bow machine-gunner)
Ausf A-C: 15 mm all around
Ausf D-G: 30 mm all around
Ausf J+: 50 mm all around
1 × 3.7 cm KwK 36 Ausf. A-G
1 × 5 cm KwK 38 Ausf. F-J
1 × 5 cm KwK 39 Ausf. J¹-M
1 × 7.5 cm KwK 37 Ausf. N
12-cylinder Maybach HL120 TRM petrol engine
300 PS (295 hp, 220 kW)
12 hp (9.6 kW) / tonne
300–320 L (66–70 imp gal; 79–85 US gal)
Road:
165 km (103 mi)
Cross-country:
85 km (53 mi)[1]
Road: 40 km/h (25 mph)
Off-road: 20 km/h (12 mph)
Initially the Panzer III had the same 3.7 cm gun as the infantry used for anti-tank work but later models were given 5 cm gun. However, this was the largest gun that could be fitted within the limitations of the turret ring and it was insufficient against Soviet T-34 and KV-1 tanks. Instead the Panzer IV which had a larger turret ring, was redesigned to mount the long-barrelled 7.5 cm KwK 40 gun and became the main German tank. The Panzer III effectively swapped roles with the Panzer IV; from 1942 the last version of the Panzer III (Panzer III N) mounted the short barrelled 7.5 cm KwK 37 L/24 that the first Panzer IVs had been fitted with.
Production of the Panzer III ceased in 1943 but the Sturmgeschütz III assault gun which had been developed from the Panzer III chassis continued in production until the end of the war.
Development history[edit]
Background[edit]
At the time, German (non-light) tanks were expected to carry out one of two primary tasks when assisting infantry in breakthroughs, exploiting 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.[2]
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).[3] 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 fulfill 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.[4]
Development[edit]
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.[5] 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.[6]
A distinct feature of the Panzer III, influenced by the British Vickers Medium Mark I tank (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,[7] 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. Unlike the Panzer IV, the Panzer III had no turret basket, merely a foot rest platform for the gunner.[a]
The Panzer III was intended as the primary battle tank of the German forces. However, when it initially met the KV-1 heavy tanks and T-34 medium 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 to the 5 cm KwK 39, 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 anti-tank guns (Panzerjaeger), 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 low-velocity gun used for the initial models of the Panzer IV and 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.[9]
Armour[edit]
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.[10] This additional frontal armor gave the Panzer III frontal protection from many light and medium Allied 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.
Foreign users[edit]
In 1943, Turkey received 22 Panzer III Ausf. Ms, with Hitler hoping the country, militarily strengthened by Nazi Germany, could possibly threaten the Soviet Union from its southern border (in any case, neutral Turkey did not participate in any form of aggression towards the USSR or the Western Allies, and eventually declared war on Nazi Germany nearing the end of WWII instead, perhaps from Allied pressure).[25] The Army of the Independent State of Croatia received 4 Ausf. N variants in the spring of 1944 and the Ustashe Militia received 20 other Ausf. Ns in the autumn of 1944.[26] Romania received a number of Panzer III Ausf. Ns for its 1st Armored Division in 1943. They were called T-3 in the Romanian army. At least 2 of them were still operational in 1945.
Norway used leftover stocks of ex-German Panzer IIIs (along with similar Sturmgeschütz III assault guns/tank destroyers) abandoned by departing Nazi occupation forces at the end of WWII up until the 1950s. In the Soviet Union, the Panzer III was one of the more common captured Nazi tanks they operated, as with the Panzer IV. At least 200, together with some StuG IIIs, fell into Soviet hands following the German defeat at the Battle of Stalingrad. The Soviets decided to upgun these captured German vehicles and two resulting designs were produced: the SG-122 self-propelled howitzer and the SU-76i assault gun. The former was not well-designed and was only built in very small numbers, with most not seeing combat action at all, while the latter was regarded as a better option of a Panzer III-based assault vehicle with a larger 75mm main gun. Aside from these locally designed variants of the Panzer III, the Soviets primarily tended to use them as their basic tank version, mainly used as second-line tanks, for reconnaissance and as mobile command posts.
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.[27]